Abstract: Recently developed cooperative diversity scheme
enables a terminal to get transmit diversity through the support of other
terminals. However, most of the introduced cooperative schemes have
a common fault of decreased transmission rate because the destination
should receive the decodable compositions of symbols from the source
and the relay. In order to achieve high data rate, we propose a
cooperative scheme that employs hierarchical modulation. This
scheme is free from the rate loss and allows seamless cooperative
communication.
Abstract: High Performance Liquid Chromatography (HPLC)
method was developed and validated for simultaneous estimation of
6-Gingerol(6G) and 6-Shogaol(6S) in joint pain relief gel containing
ginger extract. The chromatographic separation was achieved by
using C18 column, 150 x 4.6mm i.d., 5μ Luna, mobile phase
containing acetonitrile and water (gradient elution). The flow rate
was 1.0 ml/min and the absorbance was monitored at 282 nm. The
proposed method was validated in terms of the analytical parameters
such as specificity, accuracy, precision, linearity, range, limit of
detection (LOD), limit of quantification (LOQ), and determined
based on the International Conference on Harmonization (ICH)
guidelines. The linearity ranges of 6G and 6S were obtained over 20-
60 and 6-18 μg/ml respectively. Good linearity was observed over the
above-mentioned range with linear regression equation Y= 11016x-
23778 for 6G and Y = 19276x-19604 for 6S (x is concentration of
analytes in μg/ml and Y is peak area). The value of correlation
coefficient was found to be 0.9994 for both markers. The limit of
detection (LOD) and limit of quantification (LOQ) for 6G were
0.8567 and 2.8555 μg/ml and for 6S were 0.3672 and 1.2238 μg/ml
respectively. The recovery range for 6G and 6S were found to be
91.57 to 102.36 % and 84.73 to 92.85 % for all three spiked levels.
The RSD values from repeated extractions for 6G and 6S were 3.43
and 3.09% respectively. The validation of developed method on
precision, accuracy, specificity, linearity, and range were also
performed with well-accepted results.
Abstract: In internet of things (IoT) system, the communication
scheme with reliability and low power is required to connect a
terminal. Cooperative communication can achieve reliability and
lower power than multiple-input multiple-output (MIMO) system.
Cooperative communication increases the reliability with low
power, but decreases a throughput. It has a weak point that the
communication throughput is decreased. In this paper, a novel scheme
is proposed to increase the communication throughput. The novel
scheme is a transmission structure that increases transmission rate.
A decoding scheme according to the novel transmission structure is
proposed. Simulation results show that the proposed scheme increases
the throughput without bit error rate (BER) performance degradation.
Abstract: In order to achieve high data rate and increase the
spectral efficiency, multiple input multiple output (MIMO) system has
been proposed. However, multiple antennas are limited by size and
cost. Therefore, recently developed cooperative diversity scheme,
which profits the transmit diversity only with the existing hardware by
constituting a virtual antenna array, can be a solution. However, most
of the introduced cooperative techniques have a common fault of
decreased transmission rate because the destination should receive the
decodable compositions of symbols from the source and the relay. In
this paper, we propose a cooperative cyclic delay diversity (CDD)
scheme that use hierarchical modulation. This scheme is free from the
rate loss and allows seamless cooperative communication.
Abstract: Because current wireless communication requires high
reliability in a limited bandwidth environment, this paper proposes
the variable modulation scheme based on the codebook. The variable
modulation scheme adjusts transmission power using the codebook in
accordance with channel state. Also, if the codebook is composed of
many bits, the reliability is more improved by the proposed scheme.
The simulation results show that the performance of proposed scheme
has better reliability than the the performance of conventional scheme.
Abstract: Structure-borne noise is an important aspect of
offshore platform sound field. It can be generated either directly by
vibrating machineries induced mechanical force, indirectly by the
excitation of structure or excitation by incident airborne noise.
Therefore, limiting of the transmission of vibration energy
throughout the offshore platform is the key to control the structureborne
noise. This is usually done by introducing damping treatment
to the steel structures. Two types of damping treatment using onboard
are presented. By conducting a Statistical Energy Analysis
(SEA) simulation on a jack-up rig, the noise level in the source room,
the neighboring rooms, and remote living quarter cabins are
compared before and after the damping treatments been applied. The
results demonstrated that, in the source neighboring room and living
quarter area, there is a significant noise reduction with the damping
treatment applied, whereas in the source room where air-borne sound
predominates that of structure-borne sound, the impact is not
obvious. The conclusion on effective damping treatment in the
offshore platform is made which enable acoustic professionals to
implement noise control during the design stage for offshore crews’
hearing protection and habitant comfortability.
Abstract: In the cooperative transmission scheme, both the
cellular system and broadcasting system are composed. Two cellular
base stations (CBSs) communicating with a user in the cell edge use
cooperative transmission scheme in the conventional scheme. In the
case that the distance between two CBSs and the user is distant, the
conventional scheme does not guarantee the quality of the
communication because the channel condition is bad. Therefore, if the
distance between CBSs and a user is distant, the performance of the
conventional scheme is decreased. Also, the bad channel condition has
bad effects on the performance. The proposed scheme uses two relays
to communicate well with CBSs when the channel condition between
CBSs and the user is poor. Using the relay in the high attenuation
environment can obtain both advantages of the high bit error rate
(BER) and throughput performance.
Abstract: In this paper, improved performance scheme for
joint transmission (JT) is proposed in downlink (DL) coordinated
multi-point (CoMP) in case of the constraint transmission power.
This scheme is that a serving transmission point (TP) requests the
JT to an inter-TP and it selects a precoding technique according
to the channel state information (CSI) from user equipment (UE).
The simulation results show that the bit error rate (BER) and the
throughput performances of the proposed scheme provide the high
spectral efficiency and the reliable data at the cell edge.
Abstract: The conventional Wi-Fi backscatter system can only
process one-to-one communication between the Wi-Fi reader and the
Wi-Fi tag. For improvement of throughput of the conventional system,
this paper proposes the multi-to-multi communication system. In the
proposed system, the interference by the multi-to-multi
communication is effectively cancelled by the orthogonal multiple
access based on the identification code of the tag. Although the
overhead is generated by the procedure for the multi-to-multi
communication, because the procedure is processed by the Wi-Fi
protocol, the overhead is insignificant for the entire communication
procedure. From the numerical results, it is confirmed that the
proposed system has nearly proportional increased throughput in
according to the number of the tag that simultaneously participates in
communication.
Abstract: Rice bran is normally used as a raw material for rice
bran oil production or sold as feed with a low price. Conventionally,
the protein in defatted rice bran was extracted using alkaline
extraction and acid precipitation, which involves in chemical usage
and lowering some nutritious component. This study was conducted
in order to extract of rice bran protein concentrate (RBPC) from
defatted rice bran using enzymes and employing polysaccharides in a
precipitating step. The properties of RBPC obtained will be compared
to those of a control sample extracted using a conventional method.
The results showed that extraction of protein from rice bran using
enzymes exhibited the higher protein recovery compared to that
extraction with alkaline. The extraction conditions using alcalase 2%
(v/w) at 50 C, pH 9.5 gave the highest protein (2.44%) and yield
(32.09%) in extracted solution compared to other enzymes. Rice bran
protein concentrate powder prepared by a precipitation step using
alginate (protein in solution: alginate 1:0.016) exhibited the highest
protein (27.55%) and yield (6.84%). Precipitation using alginate was
better than that of acid. RBPC extracted with alkaline (ALK) or
enzyme alcalase (ALC), then precipitated with alginate (AL)
(samples RBP-ALK-AL and RBP-ALC-AL) yielded the precipitation
rate of 75% and 91.30%, respectively. Therefore, protein
precipitation using alginate was then selected. Amino acid profile of
control sample, and sample precipitated with alginate, as compared to
casein and soy protein isolated, showed that control sample showed
the highest content among all sample. Functional property study of
RBP showed that the highest nitrogen solubility occurred in pH 8-10.
There was no statically significant between emulsion capacity and
emulsion stability of control and sample precipitated by alginate.
However, control sample showed a higher of foaming capacity and
foaming stability compared to those of sample precipitated with
alginate. The finding was successful in terms of minimizing
chemicals used in extraction and precipitation steps in preparation of
rice bran protein concentrate. This research involves in a production
of value-added product in which the double amount of protein (28%)
compared to original amount (14%) contained in rice bran could be
beneficial in terms of adding to food products e.g. healthy drink with
high protein and fiber. In addition, the basic knowledge of functional
property of rice bran protein concentrate was obtained, which can be
used to appropriately select the application of this value-added
product from rice bran.
Abstract: The comprehensive CFD models have been used to
represent and study the heterogeneous combustion of biomass. In the
present work, the operation of a global flue gas circuit in the sugarcane
bagasse combustion, from wind boxes below primary air grate
supply, passing by bagasse insertion in swirl burners and boiler
furnace, to boiler bank outlet is simulated. It uses five different
meshes representing each part of this system located in sequence:
wind boxes and grate, boiler furnace, swirl burners, superheaters and
boiler bank. The model considers turbulence using standard k-ε,
combustion using EDM, radiation heat transfer using DTM with 16
ray directions and bagasse particle tracking represented by Schiller-
Naumann model. The results showed good agreement with expected
behavior found in literature and equipment design. The more detailed
results view in separated parts of flue gas system allows observing
some flow behaviors that cannot be represented by usual
simplifications like bagasse supply under homogeneous axial and
rotational vectors and others that can be represented using new
considerations like the representation of 26 thousand grate orifices by
144 rectangular inlets.
Abstract: A comprehensive CFD model is developed to
represent heterogeneous combustion and two burner designs of
supply sugar-cane bagasse into a furnace. The objective of this work
is to compare the insertion and burning of a Brazilian south-eastern
sugar-cane bagasse using a new swirl burner design against an actual
geometry under operation. The new design allows control the
particles penetration and scattering inside furnace by adjustment of
axial/tangential contributions of air feed without change their mass
flow. The model considers turbulence using RNG k-, combustion
using EDM, radiation heat transfer using DTM with 16 ray directions
and bagasse particle tracking represented by Schiller-Naumann
model. The obtained results are favorable to use of new design swirl
burner because its axial/tangential control promotes more penetration
or more scattering than actual design and allows reproduce the actual
design operation without change the overall mass flow supply.
Abstract: The aims of this study were to determine the factor
structure and psychometric properties (i.e., reliability and convergent
validity) of the Malaysian Multi-Ethnic Discrimination Scale
(MMEDS). It consists of 71-items measure experience, strategies
used and consequences of ethnic discrimination. A sample of 649
university students from one of the higher education institution in
Malaysia was asked to complete MMEDS, as well as Perceived
Ethnic and Racial Discrimination. The exploratory factor analysis on
ethnic discrimination experience extracted two factors labeled ‘unfair
treatment’ (15 items) and ‘Denial of the ethnic right’ (12 items)
which accounted for 60.92% of the total variance. The two sub scales
demonstrated clear reliability with internal consistency above .70.
The convergent validity of the Scale was supported by an expected
pattern of correlations (positive and significant correlation) between
the score of unfair treatment and denial of the ethnic right and the
score of Perceived Ethnic and Racial Discrimination by Peers Scale.
The results suggest that the MMEDS is a reliable and valid measure.
However, further studies need to be carried out in other groups of
sample as to validate the Scale.
Abstract: This paper presents a model for a modified T-junction
device for microspheres generation. The numerical model is
developed using a commercial software package: COMSOL
Multiphysics. In order to test the accuracy of the numerical model,
multiple variables, such as the flow rate of cross-flow, fluid properties,
structure, and geometry of the microdevice are applied. The results
from the model are compared with the experimental results in the
diameter of the microsphere generated. The comparison shows a good
agreement. Therefore the model is useful in further optimization of the
device and feedback control of microsphere generation if any.
Abstract: Recently, increasing the quality of experience (QoE) is
an important issue. Since performance degradation at cell edge
extremely reduces the QoE, several techniques are defined at
LTE/LTE-A standard to remove inter-cell interference (ICI). However,
the conventional techniques have disadvantage because there is a
trade-off between resource allocation and reliable communication.
The proposed scheme reduces the ICI more efficiently by using
channel state information (CSI) smartly. It is shown that the proposed
scheme can reduce the ICI with fewer resources.
Abstract: This paper proposed a silicon controller rectifier (SCR)
based ESD protection device to protect low voltage ESD for integrated
circuit. The proposed ESD protection device has low trigger voltage
and high holding voltage compared with conventional SCR-based
ESD protection devices. The proposed ESD protection circuit is
verified and compared by TCAD simulation. This paper verified
effective low voltage ESD characteristics with low trigger voltage of
5.79V and high holding voltage of 3.5V through optimization
depending on design variables (D1, D2, D3 and D4).
Abstract: In wireless communication, space-time block code (STBC), cyclic delay diversity (CDD) and space-time cyclic delay diversity (STCDD)are used as the spatial diversity schemes and have been widely studied for the reliablecommunication. If these schemes are used, the communication system can obtain the improved performance. However,the quality of the system is degraded when the distance between a source and a destination is distant in wireless communication system. In this paper, the cooperative transmission scheme using two sources is proposed and improves the performance of the wireless communication system.
Abstract: To practically apply vacuum insulation panels (VIPs)
to buildings or home appliances, VIPs have demanded long-term
lifespan with outstanding insulation performance. Service lives of
VIPs enveloped with Al-foil and three-layer Al-metallized envelope
are calculated. For Al-foil envelope, the service life is longer but edge
conduction is too large compared with the Al-metallized envelope. To
increase service life even more, the proposed double enveloping
method and metal-barrier-added enveloping method are further
analyzed. The service lives of the VIP to employ two enveloping
methods are calculated. Also, pressure increase and thermal insulation
performance characteristics are investigated. For the metalbarrier-
added enveloping method, effective thermal conductivity
increase with time is close to that of Al-foil envelope, especially, for
getter-inserted VIPs. For double enveloping method, if water vapor is
perfectly adsorbed, the effect of service life enhancement becomes
much greater. From these methods, the VIP can be guaranteed for
service life of more than 20 years.
Abstract: Vacuum Insulation Panel (VIP) can achieve very low
thermal conductivity by evacuating its inner space. Heat transfer in the
core materials of highly-evacuated VIP occurs by conduction through
the solid structure and radiation through the pore. The effect of various
scattering modes in combined conduction-radiation in VIP is
investigated through numerical analysis. The discrete ordinates
interpolation method (DOIM) incorporated with the commercial code
FLUENT® is employed. It is found that backward scattering is more
effective in reducing the total heat transfer while isotropic scattering is
almost identical with pure absorbing/emitting case of the same optical
thickness. For a purely scattering medium, the results agrees well with
additive solution with diffusion approximation, while a modified term
is added in the effect of optical thickness to backward scattering is
employed. For other scattering phase functions, it is also confirmed
that backwardly scattering phase function gives a lower effective
thermal conductivity. Thus the materials with backward scattering
properties, with radiation shields are desirable to lower the thermal
conductivity of VIPs.
Abstract: Vacuum insulation panel (VIP) is a promising thermal
insulator for buildings, refrigerator, LNG carrier and so on. In general,
it has the thermal conductivity of 2~4 mW/m·K. However, this thermal
conductivity is that measured at the center of VIP. The total effective
thermal conductivity of VIP is larger than this value due to the edge
conduction through the envelope. In this paper, the edge conduction of
VIP is examined theoretically, numerically and experimentally. To
confirm the existence of the edge conduction, numerical analysis is
performed for simple two-dimensional VIP model and a theoretical
model is proposed to calculate the edge conductivity. Also, the edge
conductivity is measured using the vacuum guarded hot plate and the
experiment is validated against numerical analysis. The results show
that the edge conductivity is dependent on the width of panel and
thickness of Al-foil. To reduce the edge conduction, it is recommended
that the VIP should be made as big as possible or made of thin Al film
envelope.