Abstract: It is essential to have a uniform and calm flow field
for a settling tank to have high performance. In general, the
recirculation zones always occurred in sedimentation tanks. The
presence of these regions may have different effects. The nonuniformity
of the velocity field, the short-circuiting at the surface and
the motion of the jet at the bed of the tank that occurs because of the
recirculation in the sedimentation layer, are affected by the geometry
of the tank. There are some ways to decrease the size of these dead
zones, which would increase the performance. One of the ways is to
use a suitable baffle configuration. In this study, the presence of
baffle with different position has been investigated by a finite volume
method, with VOF (Volume of Fluid) model. Besides, the k-ε
turbulence model is used in the numerical calculations. The results
indicate that the best position of the baffle is obtained when the
volume of the recirculation region is minimized or is divided to
smaller part and the flow field trend to be uniform in the settling
zone.
Abstract: Among the chemicals used for ammunition production, TNT (Trinitrotoluene) play a significant role since World War I and II. Various types of military weapon utilize TNT in casting process. However, the TNT casting process for warhead is difficult to control the cooling rate of the liquid TNT. This problem occurs because the casting process lacks the equipment to detect the temperature during the casting procedure This study presents the temperature detected by infrared camera to illustrate the cooling rate and cooling zone of curing, and demonstrates the optimization of TNT condition to reduce the risk of air gap occurred in the warhead which can result in the destruction afterward. Premature initiation of explosive-filled projectiles in response to set-back forces during gunfiring cause by casting defects. Finally the study can help improving the process of the TNT casting. The operators can control the curing of TNT inside the case by rising up the heating rod at the proper time. Consequently this can reduce tremendous time of rework if the air gaps occur and increase strength to lower elastic modulus. Therefore, it can be clearly concluded that the use of Infrared Cameras in this process is another method to improve the casting procedure.
Abstract: The information revealed by derivatives can help to
better characterize digital near-end crosstalk signatures with the
ultimate goal of identifying the specific aggressor signal.
Unfortunately, derivatives tend to be very sensitive to even low
levels of noise. In this work we approximated the derivatives of both
quiet and noisy digital signals using a wavelet-based technique. The
results are presented for Gaussian digital edges, IBIS Model digital
edges, and digital edges in oscilloscope data captured from an actual
printed circuit board. Tradeoffs between accuracy and noise
immunity are presented. The results show that the wavelet technique
can produce first derivative approximations that are accurate to
within 5% or better, even under noisy conditions. The wavelet
technique can be used to calculate the derivative of a digital signal
edge when conventional methods fail.
Abstract: Biological data has several characteristics that strongly differentiate it from typical business data. It is much more complex, usually large in size, and continuously changes. Until recently business data has been the main target for discovering trends, patterns or future expectations. However, with the recent rise in biotechnology, the powerful technology that was used for analyzing business data is now being applied to biological data. With the advanced technology at hand, the main trend in biological research is rapidly changing from structural DNA analysis to understanding cellular functions of the DNA sequences. DNA chips are now being used to perform experiments and DNA analysis processes are being used by researchers. Clustering is one of the important processes used for grouping together similar entities. There are many clustering algorithms such as hierarchical clustering, self-organizing maps, K-means clustering and so on. In this paper, we propose a clustering algorithm that imitates the ecosystem taking into account the features of biological data. We implemented the system using an Ant-Colony clustering algorithm. The system decides the number of clusters automatically. The system processes the input biological data, runs the Ant-Colony algorithm, draws the Topic Map, assigns clusters to the genes and displays the output. We tested the algorithm with a test data of 100 to1000 genes and 24 samples and show promising results for applying this algorithm to clustering DNA chip data.
Abstract: This paper presents a new algorithm for the channel estimation of the OFDM system based on a pilot signal for the new generation of high data rate communication systems. In orthogonal frequency division multiplexing (OFDM) systems over fast-varying fading channels, channel estimation and tracking is generally carried out by transmitting known pilot symbols in given positions of the frequency-time grid. In this paper, we propose to derive an improved algorithm based on the calculation of the mean and the variance of the adjacent pilot signals for a specific distribution of the pilot signals in the OFDM frequency-time grid then calculating of the entire unknown channel coefficients from the equation of the mean and the variance. Simulation results shows that the performance of the OFDM system increase as the length of the channel increase where the accuracy of the estimated channel will be increased using this low complexity algorithm, also the number of the pilot signal needed to be inserted in the OFDM signal will be reduced which lead to increase in the throughput of the signal over the OFDM system in compared with other type of the distribution such as Comb type and Block type channel estimation.
Abstract: The technological concepts such as wireless hospital
and portable cardiac telemetry system require the development of
physiological signal acquisition devices to be easily integrated into
the hospital database. In this paper we present the low cost, portable
wireless ECG acquisition hardware that transmits ECG signals to a
dedicated computer.The front end of the system obtains and
processes incoming signals, which are then transmitted via a
microcontroller and wireless Bluetooth module. A monitoring
purpose Bluetooth based end user application integrated with patient
database management module is developed for the computers. The
system will act as a continuous event recorder, which can be used to
follow up patients who have been resuscitatedfrom cardiac arrest,
ventricular tachycardia but also for diagnostic purposes for patients
with arrhythmia symptoms. In addition, cardiac information can be
saved into the patient-s database of the hospital.
Abstract: The standard investigational method for obstructive
sleep apnea syndrome (OSAS) diagnosis is polysomnography (PSG),
which consists of a simultaneous, usually overnight recording of
multiple electro-physiological signals related to sleep and
wakefulness. This is an expensive, encumbering and not a readily
repeated protocol, and therefore there is need for simpler and easily
implemented screening and detection techniques. Identification of
apnea/hypopnea events in the screening recordings is the key factor
for the diagnosis of OSAS. The analysis of a solely single-lead
electrocardiographic (ECG) signal for OSAS diagnosis, which may
be done with portable devices, at patient-s home, is the challenge of
the last years. A novel artificial neural network (ANN) based
approach for feature extraction and automatic identification of
respiratory events in ECG signals is presented in this paper. A
nonlinear principal component analysis (NLPCA) method was
considered for feature extraction and support vector machine for
classification/recognition. An alternative representation of the
respiratory events by means of Kohonen type neural network is
discussed. Our prospective study was based on OSAS patients of the
Clinical Hospital of Pneumology from Iaşi, Romania, males and
females, as well as on non-OSAS investigated human subjects. Our
computed analysis includes a learning phase based on cross signal
PSG annotation.
Abstract: This study was conducted to determine the
effect of abdominal exercises versus abdominal supporting
belt on abdominal efficiency and inter-recti separation
following vaginal delivery.30 primiparous post-natal women
participated in this study. Their age ranged from (25 - 35)
years and their BMI < 30 Kg/m2. Participants were assigned
randomly into 2groups, participants of group (A) used
abdominal belt from the 2nd day following delivery, till the end
of puerperium (6 weeks), while participants of group (B)
engaged into abdominal exercises program from the 2nd day
following delivery for 6 weeks. The results of the present
study revealed that although there was no statistical difference
in waist circumference between both groups, participation in
abdominal exercise program produced a pronounced reduction
in waist/hip ratio, and inter-recti separation and also caused
significant increase in abdominal muscles strength (peak
torque, maximum repetition total work and average power)
higher than the use of abdominal belt.
Abstract: The forest stand consisted of four layers. The species
composition between the third and the bottom layers was almost
similar, whereas it was almost exclusive between the top and the lower
three layers. The values of Shannon-s index H' and Pielou-s index
J ' tended to increase from the bottom layer upward, except for
H' -value of the top layer. The values of H' and J ' were 4.21 bit
and 0.73, respectively, for the total stand. High woody species
diversity of the forest depended on large trees in the upper layers,
which trend was different from a subtropical evergreen broadleaf
forest grown in silicate habitat in the northern part of Okinawa Island.
The spatial distribution of trees was overlapped between the third and
the bottom layers, whereas it was independent or slightly exclusive
between the top and the lower three layers. Mean tree weight of each
layer decreased from the top toward the bottom layer, whereas the
corresponding tree density increased from the top downward. This
relationship was analogous to the process of self-thinning plant
populations.
Abstract: Dextran is a D-glucose polymer which is produced by
Leuconostoc mesenteroides grown in a sucrose-rich media. The
organism was obtained from the Persian Type Culture Collection
(PTCC) and was transferred in MRS broth medium at 30°C and pH
6.8 for 24 h. After preparation of inoculums, organisms were
inoculated into five liquid fermentation media containing either
molasses or cheese whey or different combinations of cheese whey
and molasses. After certain fermentation period, the produced
dextran was separated and dried. Dextran yield was calculated and
significant differences in different media were observed.
Furthermore, FT-IR analysis was performed and the results showed
that there were no significant differences in the produced dextran
structures.
Abstract: Recently, the findings on the MEG iterative scheme has demonstrated to accelerate the convergence rate in solving any system of linear equations generated by using approximation equations of boundary value problems. Based on the same scheme, the aim of this paper is to investigate the capability of a family of four-point block iterative methods with a weighted parameter, ω such as the 4 Point-EGSOR, 4 Point-EDGSOR, and 4 Point-MEGSOR in solving two-dimensional elliptic partial differential equations by using the second-order finite difference approximation. In fact, the formulation and implementation of three four-point block iterative methods are also presented. Finally, the experimental results show that the Four Point MEGSOR iterative scheme is superior as compared with the existing four point block schemes.
Abstract: Antioxidant activities of ethanolic extracts of Ardisia
japonica Blume., Ageartum conyzoides Linn., and Cocculus hirsutus
Linn Diels. leaves was determined qualitatively and quantitatively in
this research. 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical
solution was used to investigate free radical scavenging activity of
these leaves extracts. Ascorbic acid (Vitamin C) was used as the
standard. In the present investigation, it is found that all of these
extracts have remarkable antioxidant activities. The EC50 values of
these ethanolic extracts were 12.72 μg/ml for A. japonica, 15.19
μg/ml for A. conyzoides, 10.68 μg/ml for C. hirsutus respectively.
Among these Myanmar medicinal plants, C. hirsutus showed higher
antioxidant activities as well as free radical scavenging activity than
black tea (Camellia sinensis), the famous antioxidant, and A.
japonica and A. conyzoides showed a rather lower antioxidant
activity than tea extracts. According to results from bioassay with
carrot discs infected with Agrobacterium tumefaciens, all extracts
showed anti-tumor activity after 3 weeks of incubation. No gall was
detected in carrot disks treated with C. hirsutus and A. japonica
extracts in the dose of 100ppm and in carrot discs treated with A.
conyzoides extract in the dose of 1000 ppm. Therefore, the research
clearly indicates that these weedy plants of dry farm land are
exceptionally advantageous for human health.
Abstract: Kuwait-s electric power system is vertically integrated
organization owned and operated by the government. For more than
five decades, the government of Kuwait has provided relatively
reliable electric services to consumers with subsidized electric
service fees. Given the country-s rapid socio-economical
development and consequently the increase of electricity demand, a
question that inflicts itself: Is it necessary to reform the power system
to face the fast growing demand? This paper recommends that the
government should consider the private sector as a partner in
operating the power system. Therefore, power system restructuring is
needed to allow such partnership. There are challenges that prevent
such restructuring. Abstract recommendations toward resolving these
challenges are proposed.
Abstract: The use of magnetic and magnetic/gold core/shell
nanoparticles in biotechnology or medicine has shown good promise
due to their hybrid nature which possesses superior magnetic and
optical properties. Some of these potential applications include
hyperthermia treatment, bio-separations, diagnostics, drug delivery
and toxin removal. Synthesis refinement to control geometric and
magnetic/optical properties, and finding functional surfactants for
biomolecular attachment, are requirements to meet application
specifics.
Various high-temperature preparative methods were used for the
synthesis of iron oxide and gold-coated iron oxide nanoparticles.
Different surface functionalities, such as 11-aminoundecanoic and
11-mercaptoundecanoic acid, were introduced on the surface of the
particles to facilitate further attachment of biomolecular functionality
and drug-like molecules. Nanoparticle thermal stability, composition,
state of aggregation, size and morphology were investigated and the
results from techniques such as Fourier Transform-Infra Red
spectroscopy (FT-IR), Ultraviolet visible spectroscopy (UV-vis),
Transmission Electron Microscopy (TEM) and thermal analysis are
discussed.
Abstract: The subject of the paper is comparative analysis of the hotel guest-s contractual liability for breaching the obligation for non-payment of hotel services in the hotel-keeper-s contract. The paper is methodologically conceived of six chapters (1. introduction, 2. comparative law sources of the hotel-keeper-s contract, 3. the guest-s obligation for payment of hotel services, 4. hotel guest's liability for non-payment, 5. the hotel-keeper-s rights due to nonpayment and 6. conclusion), which analyzes the guest-s liability for non-payment of hotel services through the international law, European law, euro-continental national laws (France, Germany, Italy, Croatia) and Anglo-American national laws (UK, USA). The paper-s results are the synthesis of answers to the set hypothesis and comparative review of hotel guest-s contractual liability for nonpayment of hotel services provided. In conclusion, it is necessary to adopt an international convention on the hotel-keeper-s contract, which would unify the institute of the hotel guest-s contractual liability for non-payment of hotel services at the international level.
Abstract: In this paper a novel scheme for watermarking digital
audio during its compression to MPEG-1 Layer III format is
proposed. For this purpose we slightly modify some of the selected
MDCT coefficients, which are used during MPEG audio
compression procedure. Due to the possibility of modifying different
MDCT coefficients, there will be different choices for embedding the
watermark into audio data, considering robustness and transparency
factors. Our proposed method uses a genetic algorithm to select the
best coefficients to embed the watermark. This genetic selection is
done according to the parameters that are extracted from the
perceptual content of the audio to optimize the robustness and
transparency of the watermark. On the other hand the watermark
security is increased due to the random nature of the genetic
selection. The information of the selected MDCT coefficients that
carry the watermark bits, are saves in a database for future extraction
of the watermark. The proposed method is suitable for online MP3
stores to pursue illegal copies of musical artworks. Experimental
results show that the detection ratio of the watermarks at the bitrate
of 128kbps remains above 90% while the inaudibility of the
watermark is preserved.
Abstract: This study aims to explore the differences and
similarities in perceptions of affective climate antecedents at the
workplace (intimacy, flexibility, employment stability, and team)
among Japanese and Thai Generations X and Y. The samples in this
study were Thai and Japanese workers who completed a work
environment questionnaire and provided demographic information.
Generational differences in perceptions (beliefs) of what factors
contribute to affective climate were investigated using t-test analysis.
Mean scores for each antecedent were ranked to determine how each
generation in each group prioritized the importance of all affective
climate antecedents. Japanese Generation Y perceived the importance
of employment stability for affective climate of their workplaces to be
significantly higher than did Japanese Generation X. Thai Generation
Y considered flexibility with a higher priority than did Thai
Generation X. Intimacy was perceived as highly important across
generations and countries in regard to affective climate. Results
suggest that managers should design workplaces for a mixture of
diverse generations, resulting in a better affective climate. Differences
in the importance of antecedents for affective climate among
Generations X and Y in two countries were clarified. In addition,
different preferences regarding work environment across Japanese
Generations X and Y and Thai Generations X and Y were discussed.
Abstract: This paper proposes a novel game theoretical
technique to address the problem of data object replication in largescale
distributed computing systems. The proposed technique draws
inspiration from computational economic theory and employs the
extended Vickrey auction. Specifically, players in a non-cooperative
environment compete for server-side scarce memory space to
replicate data objects so as to minimize the total network object
transfer cost, while maintaining object concurrency. Optimization of
such a cost in turn leads to load balancing, fault-tolerance and
reduced user access time. The method is experimentally evaluated
against four well-known techniques from the literature: branch and
bound, greedy, bin-packing and genetic algorithms. The experimental
results reveal that the proposed approach outperforms the four
techniques in both the execution time and solution quality.
Abstract: Nano sized zirconium dioxide in monoclinic phase (m-ZrO2) has been synthesized in pure form through co-precipitation processing at different calcination temperatures and has been characterized by several techniques such as XRD, FT-IR, UV-Vis Spectroscopy and SEM. The dielectric and capacitance values of the pelletized samples have been examined at room temperature as the functions of frequency. The higher dielectric constant value of the sample having larger grain size proves the strong influence of grain size on the dielectric constant.
Abstract: A new current-mode multifunction filter using minimum number of passive elements is proposed. The proposed filter has single-input and four high-impedance outputs. It uses four passive elements (two capacitors and two resistors) and four dual output second generation current conveyors. Each output provides a different filter response, namely, low-pass, high-pass, band-pass and band-reject. The sensitivity analysis is also carried out on both ideal and non-ideal filter configurations. The validity of the proposed filter is verified through PSPICE simulations.