Abstract: Multimedia security is an incredibly significant area of concern. The paper aims to discuss a robust image watermarking scheme, which can withstand geometric attacks. The source image is initially moment normalized in order to make it withstand geometric attacks. The moment normalized image is wavelet transformed. The first level wavelet transformed image is segmented into blocks if size 8x8. The product of mean and standard and standard deviation of each block is computed. The second level wavelet transformed image is divided into 8x8 blocks. The product of block mean and the standard deviation are computed. The difference between products in the two levels forms the watermark. The watermark is inserted by modulating the coefficients of the mid frequencies. The modulated image is inverse wavelet transformed and inverse moment normalized to generate the watermarked image. The watermarked image is now ready for transmission. The proposed scheme can be used to validate identification cards and financial instruments. The performance of this scheme has been evaluated using a set of parameters. Experimental results show the effectiveness of this scheme.
Abstract: The aim of our research was to evaluate the effects of
physical exercise on lipid profile and anthropometric characteristics
in young subjects, diagnosed with metabolic syndrome (MS). The
study has been developed during 28 weeks on 20 young obese
patients which have undertaken an intermittent submaximal exercise
program. After 28 weeks of physical activity, the results show
significant effects on anthropometric characteristics and serum lipid
profile of research subjects. Additionally, the results of this study
confirms the major correlation between the variations of
intraabdominal adiposity, determined ultrasonographycally,
and the changes of serum lipid concentrations, a better
correlation than it is used abdominal circumference or body
weight index.
Abstract: It has been proven that early establishment of
microbial flora in digestive tract of ruminants, has a beneficial effect
on their health condition and productivity. A probiotic compound,
made from five bacteria isolated from adult bovine cattle, was dosed
to 15 Holstein newborn calves in order to measure its capacity of
improving body weight gain and reduce diarrhea incidence. The test
was performed in the municipality of Cajicá (Colombia), at 2580
m.a.s.l., throughout rainy season, with environmental temperature
that oscillated between 4 to 25 °C. Five calves were allotted to
control (no addition of probiotic). Treatments 1, and 2 (5 calves per
group) received 10 ml Probiotic mix 1 and 2, respectively. Probiotic
mixes 1 and 2 where similar in microbial composition but different in
production process. Probiotics were added to the morning milk and
dosed on a daily basis by a month and then on a weekly basis for
three additional months. Diarrhea incidence was measured by
observance of number of animals affected in each group; each animal
was weighed up on a daily basis for obtaining weight gain and rumen
fluid samples were extracted with oro-esophageal catheter for
determining level of fiber and grain consumption.
Abstract: This paper presents a synthetic jet air blower actuated
by PZT for air blowing for air-breathing micro PEM fuel cell. The
several factors to affect the performance of air-breathing PEM fuel cell
such as air flow rate, opening ratio and cathode open type in the
cathode side were studied. Especially, an air flow rate is critical
condition to improve its performance. In this paper, we developed a
synthetic jet air blower to supply a high stoichiometric air flow. The
synthetic jet mechanism is a zero mass flux device that converts
electrical energy into the momentum. The synthetic jet actuation is
usually generated by a traditional PZT actuator, which consists of a
small cylindrical cavity, in/outlet channel and PZT diaphragms. The
flow rate of the fabricated synthetic jet air blower was 400cc/min at
550Hz and its power consumption was very low under 0.3W. The
proposed air-breathing PEM fuel cell which installed synthetic jet air
blower was higher performance and stability during continuous
operation than the air-breathing fuel cell without auxiliary device to
supply the air. The results showed that the maximum power density
was 188mW/cm2 at 400mA/cm2. This maximum power density and
durability were improved more than 40% and 20%, respectively.
Abstract: Multirate multimedia delivery applications in multihop Wireless Mesh Network (WMN) are data redundant and delay-sensitive, which brings a lot of challenges for designing efficient transmission systems. In this paper, we propose a new cross layer resource allocation scheme to minimize the receiver side distortion within the delay bound requirements, by exploring application layer Position and Value (P-V) diversity as well as the multihop Effective Capacity (EC). We specifically consider image transmission optimization here. First of all, the maximum supportable source traffic rate is identified by exploring the multihop Effective Capacity (EC) model. Furthermore, the optimal source coding rate is selected according to the P-V diversity of multirate media streaming, which significantly increases the decoded media quality. Simulation results show the proposed approach improved media quality significantly compared with traditional approaches under the same QoS requirements.
Abstract: This paper explores the implementation of adaptive
coding and modulation schemes for Multiple-Input Multiple-Output
Orthogonal Frequency Division Multiplexing (MIMO-OFDM) feedback
systems. Adaptive coding and modulation enables robust and
spectrally-efficient transmission over time-varying channels. The basic
premise is to estimate the channel at the receiver and feed this estimate
back to the transmitter, so that the transmission scheme can be
adapted relative to the channel characteristics. Two types of codebook
based channel feedback techniques are used in this work. The longterm
and short-term CSI at the transmitter is used for efficient channel
utilization. OFDM is a powerful technique employed in communication
systems suffering from frequency selectivity. Combined with
multiple antennas at the transmitter and receiver, OFDM proves to be
robust against delay spread. Moreover, it leads to significant data rates
with improved bit error performance over links having only a single
antenna at both the transmitter and receiver. The coded modulation
increases the effective transmit power relative to uncoded variablerate
variable-power MQAM performance for MIMO-OFDM feedback
system. Hence proposed arrangement becomes an attractive approach
to achieve enhanced spectral efficiency and improved error rate
performance for next generation high speed wireless communication
systems.
Abstract: Contrary to negative emotion regulation, coping with
positive moods have received less attention in adolescent adjustment.
However, some research has found that everyone is different on
dealing with their positive emotions, which affects their adaptation
and well-being. The purpose of the present study was to investigate
the relationship between positive emotions dampening and
internalizing behavior problems of adolescent in Taiwan. A survey
was conducted and 208 students (12 to14 years old) completed the
strengths and difficulties questionnaire (SDQ), the Affect Intensity
Measure, and the positive emotions dampening scale. Analysis
methods such as descriptive statistics, t-test, Pearson correlations and
multiple regression were adapted. The results were as follows:
Emotionality and internalizing problem behavior have significant
gender differences. Compared to boys, girls have a higher score on
negative emotionality and are at a higher risk for internalizing
symptoms. However, there are no gender differences on positive
emotion dampening. Additionally, in the circumstance that negative
emotionality acted as the control variable, positive emotion
dampening strategy was (positive) related to internalizing behavior
problems. Given the results of this study, it is suggested that coaching
deconstructive positive emotion strategies is to assist adolescents
with internalizing behavior problems is encouraged.
Abstract: Mobile Learning (M-Learning) is a new technology
which is to enhance current learning practices and activities for all
people especially students and academic practitioners UTP is
currently, implemented two types of learning styles which are
conventional and electronic learning. In order to improve current
learning approaches, it is necessary for UTP to implement m-learning
in UTP. This paper presents a study on the students- perceptions on
mobile utilization in the learning practices in UTP. Besides, this
paper also presents a survey that was conducted among 82 students
from System Analysis and Design (SAD) course in UTP. The survey
includes basic information of mobile devices that have been used by
the students, opinions on current learning practices and also the
opinions regarding the m-learning implementation in the current
learning practices especially in SAD course. Based on the results of
the survey, majority of the students are using the mobile devices that
can support m-learning environment. Other than that, students also
agreed that current learning practices are ineffective and they believe
that m-learning utilization can improve the effectiveness of current
learning practices.
Abstract: A number of previous studies were rarely considered
the effects of transient non-uniform balloon expansion on evaluation
of the properties and behaviors of stents during stent expansion, nor
did they determine parameters to maximize the performances driven
by mechanical characteristics. Therefore, in order to fully understand
the mechanical characteristics and behaviors of stent, it is necessary to
consider a realistic modeling of transient non-uniform balloon-stent
expansion. The aim of the study is to propose design parameters
capable of improving the ability of vascular stent through a
comparative study of seven commercial stents using finite element
analyses of a realistic transient non-uniform balloon-stent expansion
process. In this study, seven representative commercialized stents were
evaluated by finite element (FE) analysis in terms of the criteria based
on the itemized list of Food and Drug Administration (FDA) and
European Standards (prEN). The results indicate that using stents
composed of opened unit cells connected by bend-shaped link
structures and controlling the geometrical and morphological features
of the unit cell strut or the link structure at the distal ends of stent may
improve mechanical characteristics of stent. This study provides a
better method at the realistic transient non-uniform balloon-stent
expansion by investigating the characteristics, behaviors, and
parameters capable of improving the ability of vascular stent.
Abstract: In these days, multimedia data is transmitted and
processed in compressed format. Due to the decoding procedure and
filtering for edge detection, the feature extraction process of MPEG-7
Edge Histogram Descriptor is time-consuming as well as
computationally expensive. To improve efficiency of compressed
image retrieval, we propose a new edge histogram generation
algorithm in DCT domain in this paper. Using the edge information
provided by only two AC coefficients of DCT coefficients, we can get
edge directions and strengths directly in DCT domain. The
experimental results demonstrate that our system has good
performance in terms of retrieval efficiency and effectiveness.
Abstract: Thermal conductivity is an important characteristic of
a nanofluid in laminar flow heat transfer. This paper presents an
improved model for the prediction of the effective thermal
conductivity of nanofluids based on dimensionless groups. The
model expresses the thermal conductivity of a nanofluid as a function
of the thermal conductivity of the solid and liquid, their volume
fractions and particle size. The proposed model includes a parameter
which accounts for the interfacial shell, brownian motion, and
aggregation of particle. The validation of the model is verified by
applying the results obtained by the experiments of Tio2-water and
Al2o3-water nanofluids.
Abstract: One of the major causes of voltage instability is the reactive power limit of the system. Improving the system's reactive power handling capacity via Flexible AC transmission System (FACTS) devices is a remedy for prevention of voltage instability and hence voltage collapse. In this paper, the effects of SVC and STATCOM in Static Voltage Stability Margin Enhancement will be studied. AC and DC representations of SVC and STATCOM are used in the continuation power flow process in static voltage stability study. The IEEE-14 bus system is simulated to test the increasing loadability. It is found that these controllers significantly increase the loadability margin of power systems.
Abstract: Pressure wave velocity in a hydraulic system was
determined using piezo pressure sensors without removing fluid from
the system. The measurements were carried out in a low pressure
range (0.2 – 6 bar) and the results were compared with the results of
other studies. This method is not as accurate as measurement with
separate measurement equipment, but the fluid is in the actual
machine the whole time and the effect of air is taken into
consideration if air is present in the system. The amount of air is
estimated by calculations and comparisons between other studies.
This measurement equipment can also be installed in an existing
machine and it can be programmed so that it measures in real time.
Thus, it could be used e.g. to control dampers.
Abstract: The tubes in an Ammonia primary reformer furnace
operate close to the limits of materials technology in terms of the
stress induced as a result of very high temperatures, combined with
large differential pressures across the tube wall. Operation at tube
wall temperatures significantly above design can result in a rapid
increase in the number of tube failures, since tube life is very
sensitive to the absolute operating temperature of the tube. Clearly it
is important to measure tube wall temperatures accurately in order to
prevent premature tube failure by overheating.. In the present study,
the catalyst tubes in an Ammonia primary reformer has been modeled
taking into consideration heat, mass and momentum transfer as well
as reformer characteristics.. The investigations concern the effects of
tube characteristics and superficial tube wall temperatures on of the
percentage of heat flux, unconverted methane and production of
Hydrogen for various values of steam to carbon ratios. The results
show the impact of catalyst tubes length and diameters on the
performance of operating parameters in ammonia primary reformers.
Abstract: The springs located in urban areas are the outpouring
of surface water, which can serve as water supply, effluent receptors
and important local macro-drainage elements. With unplanned
occupation, non-compliance with environmental legislation and the
importance of these water bodies, it is vital to analyze the springs
within urban areas, considering the Brazilian forest code. This paper
submits an analysis and discussion methodology proposal of
environmental compliance functions of urban springs, by means of
G.I.S. - Geographic Information System analysis - and in situ
analysis. The case study included two springs which exhibit a history
of occupation along its length, with different degrees of impact. The
proposed method is effective and easy to apply, representing a
powerful tool for analyzing the environmental conditions of springs
in urban areas.
Abstract: In this paper, a simple microfluidic device for monitoring algal cell behavior is proposed. An array of algal microwells is fabricated by PDMS soft-lithography using X-ray LIGA mold, placed on a glass substrate. Two layers of replicated PDMS and substrate are attached by oxygen plasma bonding, creating a microchannel for the microfluidic system. Algal cell are loaded into the microfluidic device, which provides positive charge on the bottom surface of wells. Algal cells, which are negative charged, can be attracted to the bottom of the wells via electrostatic interaction. By varying the concentration of algal cells in the loading suspension, it is possible to obtain wells with a single cell. Liquid medium for cells monitoring are flown continuously over the wells, providing nutrient and waste exchange between the well and the main flow. This device could lead to the uncovering of the quantitative biology of the algae, which is a key to effective and extensive algal utilizations in the field of biotechnology, food industry and bioenergy research and developments.
Abstract: In this study, a vibration analysis was carried out of
symmetric angle-ply laminated composite plates with and without
square hole when subjected to compressive loads, numerically. A
buckling analysis is also performed to determine the buckling load of
laminated plates. For each fibre orientation, the compression load is
taken equal to 50% of the corresponding buckling load. In the
analysis, finite element method (FEM) was applied to perform
parametric studies, the effects of degree of orthotropy and stacking
sequence upon the fundamental frequencies and buckling loads are
discussed. The results show that the presence of a constant
compressive load tends to reduce uniformly the natural frequencies
for materials which have a low degree of orthotropy. However, this
reduction becomes non-uniform for materials with a higher degree of
orthotropy.
Abstract: This paper discusses the approach of real-time
controlling of the energy management system using the data
acquisition tool of LabVIEW. The main idea of this inspiration was
to interface the Station (PC) with the system and publish the data on
internet using LabVIEW. In this venture, controlling and switching of
3 phase AC loads are effectively and efficiently done. The phases are
also sensed through devices. In case of any failure the attached
generator starts functioning automatically. The computer sends
command to the system and system respond to the request. The
modern feature is to access and control the system world-wide using
world wide web (internet). This controlling can be done at any time
from anywhere to effectively use the energy especially in developing
countries where energy management is a big problem. In this system
totally integrated devices are used to operate via remote location.
Abstract: This paper describes a newly designed decentralized
nonlinear control strategy to control a robot manipulator. Based on the
concept of the nonlinear state feedback theory and decentralized
concept is developed to improve the drawbacks in previous works
concerned with complicate intelligent control and low cost effective
sensor. The control methodology is derived in the sense of Lyapunov
theorem so that the stability of the control system is guaranteed. The
decentralized algorithm does not require other joint angle and velocity
information. Individual Joint controller is implemented using a digital
processor with nearly actuator to make it possible to achieve good
dynamics and modular. Computer simulation result has been
conducted to validate the effectiveness of the proposed control scheme
under the occurrence of possible uncertainties and different reference
trajectories. The merit of the proposed control system is indicated in
comparison with a classical control system.
Abstract: Gas flaring is one of the most GHG emitting sources in the oil and gas industries. It is also a major way for wasting such an energy that could be better utilized and even generates revenue. Minimize flaring is an effective approach for reducing GHG emissions and also conserving energy in flaring systems. Integrating waste and flared gases into the fuel gas networks (FGN) of refineries is an efficient tool. A fuel gas network collects fuel gases from various source streams and mixes them in an optimal manner, and supplies them to different fuel sinks such as furnaces, boilers, turbines, etc. In this article we use fuel gas network model proposed by Hasan et al. as a base model and modify some of its features and add constraints on emission pollution by gas flaring to reduce GHG emissions as possible. Results for a refinery case study showed that integration of flare gas stream with waste and natural gas streams to construct an optimal FGN can significantly reduce total annualized cost and flaring emissions.