Abstract: Accurate evaluation of damping ratios involving soilstructure interaction (SSI) effects is the prerequisite for seismic design of in-situ buildings. This study proposes a combined approach to identify damping ratios of SSI systems based on ambient excitation technique. The proposed approach is illustrated with main test process, sampling principle and algorithm steps through an engineering example, as along with its feasibility and validity. The proposed approach is employed for damping ratio identification of 82 buildings in Xi-an, China. Based on the experimental data, the variation range and tendency of damping ratios of these SSI systems, along with the preliminary influence factor, are shown and discussed. In addition, a fitting curve indicates the relation between the damping ratio and fundamental natural period of SSI system.
Abstract: K-Modes is an extension of K-Means clustering algorithm, developed to cluster the categorical data, where the mean is replaced by the mode. The similarity measure proposed by Huang is the simple matching or mismatching measure. Weight of attribute values contribute much in clustering; thus in this paper we propose a new weighted dissimilarity measure for K-Modes, based on the ratio of frequency of attribute values in the cluster and in the data set. The new weighted measure is experimented with the data sets obtained from the UCI data repository. The results are compared with K-Modes and K-representative, which show that the new measure generates clusters with high purity.
Abstract: Nowadays for algae cell ultrasonication the
longitudinal ultrasonic piezosystems are used. In this paper a
possibility of creating unique ultrasonic piezoelectric system, which
would allow reducing energy losses and concentrating this energy to
a small closed volume are proposed. The current vibrating systems
whose ultrasonic energy is concentrated inside of hollow cylinder in
which water-algae mixture is flowing. Two, three or multiply
ultrasonic composite systems to concentrate total energy into a
hollow cylinder to creating strong algae cell ultrasonication are used.
The experiments and numerical FEM analysis results using diskshaped
transducer and the first biological test results on algae cell
disruption by ultrasonication are presented as well.
Abstract: Infrared focal plane arrays (IRFPA) sensors, due to
their high sensitivity, high frame frequency and simple structure, have
become the most prominently used detectors in military applications.
However, they suffer from a common problem called the fixed pattern
noise (FPN), which severely degrades image quality and limits the
infrared imaging applications. Therefore, it is necessary to perform
non-uniformity correction (NUC) on IR image. The algorithms of
non-uniformity correction are classified into two main categories, the
calibration-based and scene-based algorithms. There exist some
shortcomings in both algorithms, hence a novel non-uniformity
correction algorithm based on non-linear fit is proposed, which
combines the advantages of the two algorithms. Experimental results
show that the proposed algorithm acquires a good effect of NUC with
a lower non-uniformity ratio.
Abstract: This paper deals with the experimental investigations
of the in-cylinder tumble flows in an unfired internal combustion
engine with a flat piston at the engine speeds ranging from 400 to
1000 rev/min., and also with the dome and dome-cavity pistons at an
engine speed of 1000 rev/min., using particle image velocimetry.
From the two-dimensional in-cylinder flow measurements, tumble
flow analysis is carried out in the combustion space on a vertical
plane passing through cylinder axis. To analyze the tumble flows,
ensemble average velocity vectors are used and to characterize it,
tumble ratio is estimated. From the results, generally, we have found
that tumble ratio varies mainly with crank angle position. Also, at the
end of compression stroke, average turbulent kinetic energy is more
at higher engine speeds. We have also found that, at 330 crank angle
position, flat piston shows an improvement of about 85 and 23% in
tumble ratio, and about 24 and 2.5% in average turbulent kinetic
energy compared to dome and dome-cavity pistons respectively
Abstract: An experiment was conducted under controlled
conditions to study the effect of water extract of leaves, shoots and
roots of either Sisymbrium irio L. =SISIR and/or Descurainia
sophia (L.) Schur =DESSO on the germination and primary growth
of wheat. A split-split plot experiment in CRD with three
replications was used. The main plots were the type of weed: i.e.
SISIR and DESSO and the sub-plots were type of organ: i.e. leaf,
stem and root and, the sub-sub plots were concentration of the
water extract of each organ of the weeds: i.e. 0, 2, 4 and 8 % w/v.
The plant materials were cut in 2-3 cm pieces and then were
ground in a blender. The crushed materials were weighed
according to experimental protocol and the final volume was
reached to 100 ml in distilled water in dark bottles. All bottles were
put on a shaker for 24 hours. The solutions were filtered by muslin
cloth. Whatman paper, 9 cm in diameter, were put in petri dishes
and twenty seeds of wheat were put on it and 5 ml distilled water
or water extract of weeds were added to each petri dish. All petri
dishes were put in constant temperature of 15 0C incubator.
The results showed that the SISIR water extract had a greater
inhibitory effects on germination and primary growth of wheat
than those of DESSO water extract. The water extracts of the
leaves of both weeds had the greatest inhibitory effects on
germination and primary growth of wheat, compared to those of
stems and roots. Increasing the concentration of water extract of
leaves, stems and roots of both weeds up to 8 % caused the greatest
inhibitory effects to wheat and reduced the germination rate and
primary growth of it linearly.
Abstract: The paper presents a set of guidelines for analysis of industrial embedded distributed systems and introduces a mathematical model derived from these guidelines. In this study, the author examines a set of modern communication technologies that are or possibly can be used to build communication links between the subsystems of a distributed embedded system. An investigation of these guidelines results in a algorithm for analysis of specific use cases of target technologies. A goal of the paper acts as an important base for ongoing research on comparison of communication technologies. The author describes the principles of the model and presents results of the test calculations. Practical implementation of target technologies and empirical experiment data are based on a practical experience during the design and test of specific distributed systems in Latvian market.
Abstract: Object-oriented simulation is considered one of the most sophisticated techniques that has been widely used in planning, designing, executing and maintaining construction projects. This technique enables the modeler to focus on objects which is extremely important for thorough understanding of a system. Thus, identifying an object is an essential point of building a successful simulation model. In a maintenance process an object is a maintenance work order (MWO). This study demonstrates a maintenance simulation model for the building maintenance division of Saudi Consolidated Electric Company (SCECO) in Dammam, Saudi Arabia. The model focused on both types of maintenance processes namely: (1) preventive maintenance (PM) and (2) corrective maintenance (CM). It is apparent from the findings that object-oriented simulation is a good diagnostic and experimental tool. This is because problems, limitations, bottlenecks and so forth are easily identified. These features are very difficult to obtain when using other tools.
Abstract: In this study, cometabolic biodegradation of
chloroform was experimented with mixed cultures in the presence of
various organic solvents like methanol, ethanol, isopropanol, acetone,
acetonitrile and toluene as these are predominant discharges in
pharmaceutical industries. Toluene and acetone showed higher
specific chloroform degradation rate when compared to other
compounds. Cometabolic degradation of chloroform was further
confirmed by observation of free chloride ions in the medium. An
extended Haldane model, incorporating the inhibition due to
chloroform and the competitive inhibition between primary
substrates, was developed to predict the biodegradation of primary
substrates, cometabolic degradation of chloroform and the biomass
growth. The proposed model is based on the use of biokinetic
parameters obtained from single substrate degradation studies. The
model was able to satisfactorily predict the experimental results of
ternary and quaternary mixtures. The proposed model can be used for
predicting the performance of bioreactors treating discharges from
pharmaceutical industries.
Abstract: Delivering streaming video over wireless is an
important component of many interactive multimedia applications
running on personal wireless handset devices. Such personal devices
have to be inexpensive, compact, and lightweight. But wireless
channels have a high channel bit error rate and limited bandwidth.
Delay variation of packets due to network congestion and the high bit
error rate greatly degrades the quality of video at the handheld
device. Therefore, mobile access to multimedia contents requires
video transcoding functionality at the edge of the mobile network for
interworking with heterogeneous networks and services. Therefore,
to guarantee quality of service (QoS) delivered to the mobile user, a
robust and efficient transcoding scheme should be deployed in
mobile multimedia transporting network. Hence, this paper
examines the challenges and limitations that the video transcoding
schemes in mobile multimedia transporting network face. Then
handheld resources, network conditions and content based mobile
and wireless video transcoding is proposed to provide high QoS
applications. Exceptional performance is demonstrated in the
experiment results. These experiments were designed to verify and
prove the robustness of the proposed approach. Extensive
experiments have been conducted, and the results of various video
clips with different bit rate and frame rate have been provided.
Abstract: The use of buffer thresholds, blocking and adequate
service strategies are well-known techniques for computer networks
traffic congestion control. This motivates the study of series queues
with blocking, feedback (service under Head of Line (HoL) priority
discipline) and finite capacity buffers with thresholds. In this paper,
the external traffic is modelled using the Poisson process and the
service times have been modelled using the exponential distribution.
We consider a three-station network with two finite buffers, for
which a set of thresholds (tm1 and tm2) is defined. This computer
network behaves as follows. A task, which finishes its service at
station B, gets sent back to station A for re-processing with
probability o. When the number of tasks in the second buffer exceeds
a threshold tm2 and the number of task in the first buffer is less than
tm1, the fed back task is served under HoL priority discipline. In
opposite case, for fed backed tasks, “no two priority services in
succession" procedure (preventing a possible overflow in the first
buffer) is applied. Using an open Markovian queuing schema with
blocking, priority feedback service and thresholds, a closed form
cost-effective analytical solution is obtained. The model of servers
linked in series is very accurate. It is derived directly from a twodimensional
state graph and a set of steady-state equations, followed
by calculations of main measures of effectiveness. Consequently,
efficient expressions of the low computational cost are determined.
Based on numerical experiments and collected results we conclude
that the proposed model with blocking, feedback and thresholds can
provide accurate performance estimates of linked in series networks.
Abstract: This research aims to study the appropriate model of
Science teaching for students, academic achievement and to survey
students- attitudes toward using appropriate for students in
Mathayomsuksa 3 in Ang-Thong province. The research results were
as follows:
1. The appropriate model of Science teaching for Mathayomsuksa
3 students in Ang-Thong province including these following five
steps: Step 1. The introduction of the lessons. Step 2. Setting the
hypothesis. Step 3. Doing the experiment /survey. Step 4. Making
conclusion. Step 5. Applying to daily life or other subjects.
2. There is no significant difference between using appropriate
model teaching and regular teaching at 0.05 level significant
difference.
3. There is a significant difference between before and after
teaching using appropriate model of Science teaching at 0.05 level.
4. The satisfaction of students- attitudes to using the appropriate
model of Science teaching for students was in intermediate level.
Abstract: The quantified residence time distribution (RTD)
provides a numerical characterization of mixing in a reactor, thus
allowing the process engineer to better understand mixing
performance of the reactor.This paper discusses computational
studies to investigate flow patterns in a two impinging streams
cyclone reactor(TISCR) . Flow in the reactor was modeled with
computational fluid dynamics (CFD). Utilizing the Eulerian-
Lagrangian approach, implemented in FLUENT (V6.3.22), particle
trajectories were obtained by solving the particle force balance
equations. From simulation results obtained at different Δts, the mean
residence time (tm) and the mean square deviation (σ2) were
calculated. a good agreement can be observed between predicted and
experimental data. Simulation results indicate that the behavior of
complex reactor systems can be predicted using the CFD technique
with minimum data requirement for validation.
Abstract: A horizontal anaerobic digester was developed and
tested in pilot scale for Korean food waste with high water contents
(>80%). The hydrogen sulfide in the biogas was removed by a
biological desulfurization equipment integrated in the horizontal
digester. A mixer of the horizontal digester was designed to easily
remove the sediment in the bottom and scum layers on surface in the
digester. Experimental result for 120 days of operation of the pilot
plant showed a high removal efficiency of 81.2% for organic
substance and high stability during the whole operation period were
acquired. Also food waste was treated at high organic loading rates
over 4 kg•VS/m3∙day and a methane gas production rate of 0.62
m3/kg•VSremoved was accomplished.
The biological desulfurization equipment inside the horizontal
digester was proven to be an economic and effective method to reduce
the biogas desulfurization cost by removing hydrogen sulfide more
than 90% without external desulfurization equipments.
Abstract: This paper presents design and implements the
T-DOF PI controller design for a speed control of induction motor.
The voltage source inverter type space vector pulse width modulation
technique is used the drive system. This scheme leads to be able to
adjust the speed of the motor by control the frequency and amplitude
of the input voltage. The ratio of input stator voltage to frequency
should be kept constant. The T-DOF PI controller design by root
locus technique is also introduced to the system for regulates and
tracking speed response. The experimental results in testing the 120
watt induction motor from no-load condition to rated condition show
the effectiveness of the proposed control scheme.
Abstract: In this paper, a new secure watermarking scheme for
color image is proposed. It splits the watermark into two shares using
(2, 2)- threshold Visual Cryptography Scheme (V CS) with Adaptive
Order Dithering technique and embeds one share into high textured
subband of Luminance channel of the color image. The other share
is used as the key and is available only with the super-user or the
author of the image. In this scheme only the super-user can reveal
the original watermark. The proposed scheme is dynamic in the sense
that to maintain the perceptual similarity between the original and the
watermarked image the selected subband coefficients are modified
by varying the watermark scaling factor. The experimental results
demonstrate the effectiveness of the proposed scheme. Further, the
proposed scheme is able to resist all common attacks even with strong
amplitude.
Abstract: The possibility of producing drinking water from
brackish ground water using Vacuum membrane distillation (VMD)
process was studied. It is a rising technology for seawater or brine
desalination process. The process simply consists of a flat sheet
hydrophobic micro porous PTFE membrane and diaphragm vacuum
pump without a condenser for the water recovery or trap. In this
work, VMD performance was investigated for aqueous NaCl solution
and natural ground water. The influence of operational parameters
such as feed flow rate (30 to 55 l/h), feed temperature (313 to 333 K),
feed salt concentration (5000 to 7000 mg/l) and permeate pressure
(1.5 to 6 kPa) on the membrane distillation (MD) permeation flux
have been investigated. The maximum flux reached to 28.34 kg/m2 h
at feed temperature, 333 K; vacuum pressure, 1.5 kPa; feed flow rate,
55 l/h and feed salt concentration, 7000 mg/l. The negligible effects
in the reduction of permeate flux found over 150 h experimental run
for salt water. But for the natural ground water application over 75 h,
scale deposits observed on the membrane surface and 29% reduction
in the permeate flux over 75 h. This reduction can be eliminated by
acidification of feed water. Hence, promote the research attention in
apply of VMD for the ground water purification over today-s
conventional RO operation.
Abstract: Indices summarizing community structure are used to
evaluate fundamental community ecology, species interaction,
biogeographical factors, and environmental stress. Some of these
indices are insensitive to gross community changes induced by
contaminants of pollution. Diversity indices and similarity indices are
reviewed considering their ecological application, both theoretical
and practical. For some useful indices, empirical equations are given
to calculate the expected maximum value of the indices to which the
observed values can be related at any combination of sample sizes at
the experimental sites. This paper examines the effects of sample size
and diversity on the expected values of diversity indices and
similarity indices, using various formulae. It has been shown that all
indices are strongly affected by sample size and diversity. In some
indices, this influence is greater than the others and an attempt has
been made to deal with these influences.
Abstract: A novel calibration approach that aims to reduce
ASM2d parameter subsets and decrease the model complexity is
presented. This approach does not require high computational
demand and reduces the number of modeling parameters required to
achieve the ASMs calibration by employing a sensitivity and iteration
methodology. Parameter sensitivity is a crucial factor and the
iteration methodology enables refinement of the simulation parameter
values. When completing the iteration process, parameters values are
determined in descending order of their sensitivities. The number of
iterations required is equal to the number of model parameters of the
parameter significance ranking. This approach was used for the
ASM2d model to the evaluated EBPR phosphorus removal and it was
successful. Results of the simulation provide calibration parameters.
These included YPAO, YPO4, YPHA, qPHA, qPP, μPAO, bPAO, bPP, bPHA,
KPS, YA, μAUT, bAUT, KO2 AUT, and KNH4 AUT. Those parameters were
corresponding to the experimental data available.
Abstract: As it is known, buoyancy and drag forces rule bubble's rise velocity in a liquid column. These forces are strongly dependent on fluid properties, gravity as well as equivalent's diameter. This study reports a set of bubble rising velocity experiments in a liquid column using water or glycerol. Several records of terminal velocity were obtained. The results show that bubble's rise terminal velocity is strongly dependent on dynamic viscosity effect. The data set allowed to have some terminal velocities data interval of 8.0 ? 32.9 cm/s with Reynolds number interval 1.3 -7490. The bubble's movement was recorded with a video camera. The main goal is to present an original set data and results that will be discussed based on two-phase flow's theory. It will also discussed, the prediction of terminal velocity of a single bubble in liquid, as well as the range of its applicability. In conclusion, this study presents general expressions for the determination of the terminal velocity of isolated gas bubbles of a Reynolds number range, when the fluid proprieties are known.