Abstract: For the sensor network to operate successfully, the active nodes should maintain both sensing coverage and network connectivity. Furthermore, scheduling sleep intervals plays critical role for energy efficiency of wireless sensor networks. Traditional methods for sensor scheduling use either sensing coverage or network connectivity, but rarely both. In this paper, we use random scheduling for sensing coverage and then turn on extra sensor nodes, if necessary, for network connectivity. Simulation results have demonstrated that the number of extra nodes that is on with upper bound of around 9%, is small compared to the total number of deployed sensor nodes. Thus energy consumption for switching on extra sensor node is small.
Abstract: The aim of the study was to determine how different
ripening processes (traditional vs. industrial) influenced the
proteolysis in traditional Serbian dry-fermented sausage Petrovská
klobása. The obtained results indicated more intensive pH decline
(0.7 units after 9 days) in industrially ripened products (I), what had a
positive impact on drying process and proteolytic changes in these
samples. Thus, moisture content in I sausages was lower at each
sampling time, amounting 24.7% at the end of production period
(90 days). Likewise, the process of proteolysis was more pronounced
in I samples, resulting in higher contents of non-protein nitrogen
(NPN) and free amino acids nitrogen (FAAN), as well as in faster
and more intensive degradation of myosin (≈220 kDa), actin (≈45
kDa) and other polypeptides during processing. Consequently, the
appearance and accumulation of several protein fragments were
registered.
Abstract: Most of the drugs used for pharmaceutical purposes
are poorly water-soluble drugs. About 40% of all newly discovered
drugs are lipophilic and the numbers of lipophilic drugs seem to
increase more and more. Drug delivery systems such as
nanoparticles, micelles or liposomes are applied to improve their
solubility and thus their bioavailability. Besides various techniques of
solubilization, oil-in-water emulsions are often used to incorporate
lipophilic drugs into the oil phase. To stabilize emulsions surface
active substances (surfactants) are generally used. An alternative
method to avoid the application of surfactants was of great interest.
One possibility is to develop O/W-emulsion without any addition of
surface active agents or the so called “surfactant-free emulsion or
SFE”. The aim of this study was to develop and characterize SFE as a
drug carrier by varying the production conditions. Lidocaine base
was used as a model drug. The injection method was developed.
Effects of ultrasound as well as of temperature on the properties of
the emulsion were studied. Particle sizes and release were
determined. The long-term stability up to 30 days was performed.
The results showed that the surfactant-free O/W emulsions with
pharmaceutical oil as drug carrier can be produced.
Abstract: Today air-core coils (ACC) are a viable alternative to
ferrite-core coils in a range of applications due to their low induction
effect. An analytical study was carried out and the results were used as
a guide to understand the relationship between the magnet-coil
distance and the resulting attractive magnetic force. Four different
ACC models were fabricated for experimental study. The variation in
the models included the dimensions, the number of coil turns and the
current supply to the coil. Comparison between the analytical and
experimental results for all the models shows an average discrepancy
of less than 10%. An optimized ACC design was selected for the
scanner which can provide maximum magnetic force.
Abstract: In order to study of The Effect of seed inoculation
with Pseudomonas putida+Bacillus lentus on yield and yield
components of wheat (Triticum aestivum L.) cultivars, an experiment
was carried out as factorial based on Randomized Complete Block
Design (RCBD) in Agricultural Research Station of Shahrood
University of Technology. Results showed that inoculation with
Pseudomonas putida+Bacillus lentus promoted seed germination.
Also, inoculation with Pseudomonas putida+Bacillus lentus
significantly affected grain yield, Number of spikes per m2,
Number of grain per spike and 1000-seed weight and There was not
statistically significant difference between Chamran and Pishtaz
cultivars . Finally, the dosages of chemical fertilizers currently
applied in commercial wheat field in Iran (Shahrood region) could be
reduced through proper combination of Pseudomonas
putida+Bacillus lentus inoculation plus fertilization.
Abstract: Tip vortex cavitation is one of well known patterns of
cavitation phenomenon which occurs in axial pumps. This pattern of
cavitation occurs due to pressure difference between the pressure and
suction sides of blades of an axial pump. Since the pressure in the
pressure side of the blade is higher than the pressure in its suction
side, thus a very small portion of liquid flow flows back from
pressure side to the suction side. This fact is cause of tip vortex
cavitation and gap cavitation that may occur in axial pumps. In this
paper the results of our experimental investigation about movement
of tip vortex cavitation along blade edge due to reduction of pump
flow rate in an axial pump is reported. Results show that reduction of
pump flow rate in conjunction with increasing of outlet pressure
causes movement of tip vortex cavitation along blade edge towards
the blade tip. Results also show that by approaching tip vortex
cavitation to the blade tip, vortex tip pattern of cavitation replaces
with a cavitation phenomenon on the blade tip. Furthermore by
further reduction of pump flow rate and increasing of outlet pressure,
an unstable cavitation phenomenon occurs between each blade
leading edge and the next blade trailing edge.
Abstract: Selective oxidation of H2S to elemental sulfur in a
fixed bed reactor over newly synthesized alumina nanocatalysts was
physio-chemically investigated and results compared with a
commercial Claus catalyst. Amongst these new materials, Al2O3-
supported sodium oxide prepared with wet chemical technique and
Al2O3 nanocatalyst prepared with spray pyrolysis method were the
most active catalysts for selective oxidation of H2S to elemental
sulfur. Other prepared nanocatalysts were quickly deactivated,
mainly due to the interaction with H2S and conversion into sulfides.
Abstract: Commercially available lipases (Candida antarctica lipase B, Novozyme 435, Thermomyces lanuginosus lipase, and Lipozyme TL IM), as well as sol-gel immobilized lipases, have been screened for their ability to acylate regioselectively xylitol, sorbitol, and mannitol with a phenolic ester in a binary mixture of t-butanol and dimethylsulfoxide. HPLC and MALDI-TOF MS analysis revealed the exclusive formation of monoesters for all studied sugar alcohols. The lipases immobilized by the sol-gel entrapment method proved to be efficient catalysts, leading to high conversions (up to 60%) in the investigated acylation reactions. From a sequence of silane precursors with different nonhydrolyzable groups in their structure, the presence of octyl and i-butyl group was most beneficial for the catalytic activity of sol-gel entrapped lipases in the studied process.
Abstract: This paper describes a new method for affine parameter
estimation between image sequences. Usually, the parameter
estimation techniques can be done by least squares in a quadratic
way. However, this technique can be sensitive to the presence
of outliers. Therefore, parameter estimation techniques for various
image processing applications are robust enough to withstand the
influence of outliers. Progressively, some robust estimation functions
demanding non-quadratic and perhaps non-convex potentials adopted
from statistics literature have been used for solving these. Addressing
the optimization of the error function in a factual framework for
finding a global optimal solution, the minimization can begin with
the convex estimator at the coarser level and gradually introduce nonconvexity
i.e., from soft to hard redescending non-convex estimators
when the iteration reaches finer level of multiresolution pyramid.
Comparison has been made to find the performance of the results
of proposed method with the results found individually using two
different estimators.
Abstract: In H.264/AVC video encoding, rate-distortion
optimization for mode selection plays a significant role to achieve
outstanding performance in compression efficiency and video quality.
However, this mode selection process also makes the encoding
process extremely complex, especially in the computation of the ratedistortion
cost function, which includes the computations of the sum
of squared difference (SSD) between the original and reconstructed
image blocks and context-based entropy coding of the block. In this
paper, a transform-domain rate-distortion optimization accelerator
based on fast SSD (FSSD) and VLC-based rate estimation algorithm
is proposed. This algorithm could significantly simplify the hardware
architecture for the rate-distortion cost computation with only
ignorable performance degradation. An efficient hardware structure
for implementing the proposed transform-domain rate-distortion
optimization accelerator is also proposed. Simulation results
demonstrated that the proposed algorithm reduces about 47% of total
encoding time with negligible degradation of coding performance.
The proposed method can be easily applied to many mobile video
application areas such as a digital camera and a DMB (Digital
Multimedia Broadcasting) phone.
Abstract: Wireless LAN technologies have picked up
momentum in the recent years due to their ease of deployment, cost
and availability. The era of wireless LAN has also given rise to
unique applications like VOIP, IPTV and unified messaging.
However, these real-time applications are very sensitive to network
and handoff latencies. To successfully support these applications,
seamless roaming during the movement of mobile station has become
crucial. Nowadays, centralized architecture models support roaming
in WLANs. They have the ability to manage, control and
troubleshoot large scale WLAN deployments. This model is managed
by Control and Provision of Wireless Access Point protocol
(CAPWAP). This paper covers the CAPWAP architectural solution
along with its proposals that have emerged. Based on the literature
survey conducted in this paper, we found that the proposed
algorithms to reduce roaming latency in CAPWAP architecture do
not support seamless roaming. Additionally, they are not sufficient
during the initial period of the network. This paper also suggests
important design consideration for mobility support in future
centralized IEEE 802.11 networks.
Abstract: When a high DC voltage is applied to a capacitor with
strongly asymmetrical electrodes, it generates a mechanical force that
affects the whole capacitor. This phenomenon is most likely to be
caused by the motion of ions generated around the smaller of the two
electrodes and their subsequent interaction with the surrounding
medium. A method to measure this force has been devised and used.
A formula describing the force has also been derived. After
comparing the data gained through experiments with those acquired
using the theoretical formula, a difference was found above a certain
value of current. This paper also gives reasons for this difference.
Abstract: In this paper, a joint source-channel coding (JSCC) scheme for time-varying channels is presented. The proposed scheme uses hierarchical framework for both source encoder and transmission via QAM modulation. Hierarchical joint source channel codes with hierarchical QAM constellations are designed to track the channel variations which yields to a higher throughput by adapting certain parameters of the receiver to the channel variation. We consider the problem of still image transmission over time-varying channels with channel state information (CSI) available at 1) receiver only and 2) both transmitter and receiver being informed about the state of the channel. We describe an algorithm that optimizes hierarchical source codebooks by minimizing the distortion due to source quantizer and channel impairments. Simulation results, based on image representation, show that, the proposed hierarchical system outperforms the conventional schemes based on a single-modulator and channel optimized source coding.
Abstract: Korea Train eXpress (KTX) is now being operated,
which allows Korea being one of the countries that operates the
high-speed rail system. The high-speed rail has its advantage of short
time transportation of population and materials, which lead to many
researches performed in this matter. In the case of high speed classical
trackbed system, the maintenance and usability of gravel ballast
system is costly. Recently, the concrete trackbed structure has been
introduced as a replacement of classical trackbed system. In this case,
the sleeper plays a critical role. Current study investigated to develop
the track sleepers readily applicable to the top of the asphalt trackbed,
as part of the trcakbed study utilizing the asphalt material. Among
many possible shapes and design of sleepers, current study proposed
two types of wide-sleepers according to the shear-key installation
method. The structural behavior analysis and safety evaluation on each
case was conducted using Korean design standard.
Abstract: This paper describes an efficient and practical method
for economic dispatch problem in one and two area electrical power
systems with considering the constraint of the tie transmission line
capacity constraint. Direct search method (DSM) is used with some
equality and inequality constraints of the production units with any
kind of fuel cost function. By this method, it is possible to use several
inequality constraints without having difficulty for complex cost
functions or in the case of unavailability of the cost function
derivative. To minimize the number of total iterations in searching,
process multi-level convergence is incorporated in the DSM.
Enhanced direct search method (EDSM) for two area power system
will be investigated. The initial calculation step size that causes less
iterations and then less calculation time is presented. Effect of the
transmission tie line capacity, between areas, on economic dispatch
problem and on total generation cost will be studied; line
compensation and active power with reactive power dispatch are
proposed to overcome the high generation costs for this multi-area
system.
Abstract: Interior brick-infill partitions are usually considered as
non-structural components, and only their weight is accounted for in
practical structural design. In this study, the brick-infill panels are
simulated by compression struts to clarify their effect on the
progressive collapse potential of an earthquake-resistant RC building.
Three-dimensional finite element models are constructed for the RC
building subjected to sudden column loss. Linear static analyses are
conducted to investigate the variation of demand-to-capacity ratio
(DCR) of beam-end moment and the axial force variation of the beams
adjacent to the removed column. Study results indicate that the
brick-infill effect depends on their location with respect to the
removed column. As they are filled in a structural bay with a shorter
span adjacent to the column-removed line, more significant reduction
of DCR may be achieved. However, under certain conditions, the
brick infill may increase the axial tension of the two-span beam
bridging the removed column.
Abstract: In recent years in Kazakhstan, as well as in all countries, we have been talking not only about the professional stress, but also professional Burnout Syndrome of employees. Burnout is essentially a response to chronic emotional stress – manifests itself in the form of chronic fatigue, despondency, unmotivated aggression, anger, and others. This condition is due to mental fatigue among teachers as a sort of payment for overstrain when professional commitments include the impact of “heat your soul", emotional investment. The emergence of professional Burnout among teachers is due to the system of interrelated and mutually reinforcing factors relating to the various levels of the personality: individually-psychological level is psychodynamic special subject characteristics of valuemotivational sphere and formation of skills and habits of selfregulation; the socio-psychological level includes especially the Organization and interpersonal interaction of a teacher. Signs of the Burnout were observed in 15 testees, and virtually a symptom could be observed in every teacher. As a result of the diagnosis 48% of teachers had the signs of stress (phase syndrome), resulting in a sense of anxiety, mood, heightened emotional susceptibility. The following results have also been got:-the fall of General energy potential – 14 pers. -Psychosomatic and psycho vegetative syndrome – 26 pers. -emotional deficit-34 pers. -emotional Burnout Syndrome-6 pers. The problem of professional Burnout of teachers in the current conditions should become not only meaningful, but particularly relevant. The quality of education of the younger generation depends on professional development; teachers- training level, and how “healthy" teachers are. That is why the systematic maintenance of pedagogic-professional development for teachers (including disclosure of professional Burnout Syndrome factors) takes on a special meaning.
Abstract: This paper proposes a Fuzzy Expert System design to
determine the wearing properties of nitrided and non nitrided steel.
The proposed Fuzzy Expert System approach helps the user and the
manufacturer to forecast the wearing properties of nitrided and non
nitrided steel under specified laboratory conditions. Surfaces of the
engineering components are often nitrided for improving wear,
corosion, fatigue specifications. A major property of nitriding
process is reducing distortion and wearing of the metalic alloys. A
Fuzzy Expert System was developed for determining the wearing and
durability properties of nitrided and non nitrided steels that were
tested under different loads and different sliding speeds in the
laboratory conditions.
Abstract: The ever increasing product diversity and competition on the market of goods and services has dictated the pace of growth in the number of advertisements. Despite their admittedly diminished effectiveness over the recent years, advertisements remain the favored method of sales promotion. Consequently, the challenge for an advertiser is to explore every possible avenue of making an advertisement more noticeable, attractive and impellent for consumers. One way to achieve this is through invoking celebrity endorsements. On the one hand, the use of a celebrity to endorse a product involves substantial costs, however, on the other hand, it does not immediately guarantee the success of an advertisement. The question of how celebrities can be used in advertising to the best advantage is therefore of utmost importance. Celebrity endorsements have become commonplace: empirical evidence indicates that approximately 20 to 25 per cent of advertisements feature some famous person as a product endorser. The popularity of celebrity endorsements demonstrates the relevance of the topic, especially in the context of the current global economic downturn, when companies are forced to save in order to survive, yet simultaneously to heavily invest in advertising and sales promotion. The issue of the effective use of celebrity endorsements also figures prominently in the academic discourse. The study presented below is thus aimed at exploring what qualities (characteristics) of a celebrity endorser have an impact on the ffectiveness of the advertisement in which he/she appears and how.
Abstract: Conventional concentrically-braced frame (CBF)
systems have limited drift capacity before brace buckling and related
damage leads to deterioration in strength and stiffness. Self-centering
concentrically-braced frame (SC-CBF) systems have been developed
to increase drift capacity prior to initiation of damage and minimize
residual drift. SC-CBFs differ from conventional CBFs in that the
SC-CBF columns are designed to uplift from the foundation at a
specified level of lateral loading, initiating a rigid-body rotation
(rocking) of the frame. Vertically-aligned post-tensioning bars resist
uplift and provide a restoring force to return the SC-CBF columns to
the foundation (self-centering the system). This paper presents a
parametric study of different prototype buildings using SC-CBFs.
The bay widths of the SC-CBFs have been varied in these buildings
to study different geometries. Nonlinear numerical analyses of the
different SC-CBFs are presented to illustrate the effect of frame
geometry on the behavior and dynamic response of the SC-CBF
system.