Abstract: Non-isothermal stagnation-point flow with consideration of thermal radiation is studied numerically. A set of partial differential equations that governing the fluid flow and energy is converted into a set of ordinary differential equations which is solved by Runge-Kutta method with shooting algorithm. Dimensionless wall temperature gradient and temperature boundary layer thickness for different combinaton of values of Prandtl number Pr and radiation parameter NR are presented graphically. Analyses of results show that the presence of thermal radiation in the stagnation-point flow is to increase the temperature boundary layer thickness and decrease the dimensionless wall temperature gradient.
Abstract: In this work, sorption of nickel from aqueous solution on hypnea valentiae, red macro algae, was investigated. Batch experiments have been carried out to find the effect of various parameters such as pH, temperature, sorbent dosage, metal concentration and contact time on the sorption of nickel using hypnea valentiae. Response surface methodology (RSM) is employed to optimize the process parameters. Based on the central composite design, quadratic model was developed to correlate the process variables to the response. The most influential factor on each experimental design response was identified from the analysis of variance (ANOVA). The optimum conditions for the sorption of nickel were found to be: pH – 5.1, temperature – 36.8oC, sorbent dosage – 5.1 g/L, metal concentration – 100 mg/L and contact time – 30 min. At these optimized conditions the maximum removal of nickel was found to be 91.97%. A coefficient of determination R2 value 0.9548 shows the fitness of response surface methodology in this work.
Abstract: In recent years there has been a continuous increase of
axle loads, tonnage, train speed and train length which has increased
both the productivity in the rail sector and the risk of rail breaks and
derailments. On the other hand, the environmental requirements (e.g.
noise reduction) for railway operations will become tighter in the
future. In our research we developed a new composite material which
does not change braking properties, is capable of taking extremely
high pressure loads, reduces noise and is environmentally friendly.
Part of our research was also the development of technology which
will be able to apply this material to the rail. The result of our
research was the system which reduces the wear out significantly and
almost completely eliminates the squealing noise at the same time,
and by using only one special material.
Abstract: RFID system, in which we give identification number to each item and detect it with radio frequency, supports more variable service than barcode system can do. For example, a refrigerator with RFID reader and internet connection will automatically notify expiration of food validity to us. But, in spite of its convenience, RFID system has some security threats, because anybody can get ID information of item easily. One of most critical threats is privacy invasion. Existing privacy protection schemes or systems have been proposed, and these schemes or systems defend normal users from attempts that any attacker tries to get information using RFID tag value. But, these systems still have weakness that attacker can get information using analogous value instead of original tag value. In this paper, we mention this type of attack more precisely and suggest 'Tag Broker Model', which can defend it. Tag broker in this model translates original tag value to random value, and user can only get random value. Attacker can not use analogous tag value, because he/she is not able to know original one from it.
Abstract: Collaborative planning, forecasting and
replenishment (CPFR) coordinates the various supply chain
management activities including production and purchase planning,
demand forecasting and inventory replenishment between supply
chain trading partners. This study proposes a systematic way of
analyzing CPFR supporting factors using fuzzy cognitive map
(FCM) approach. FCMs have proven particularly useful for solving
problems in which a number of decision variables and
uncontrollable variables are causally interrelated. Hence the FCMs
of CPFR are created to show the relationships between the factors
that influence on effective implementation of CPFR in the supply
chain.
Abstract: This research is aimed at studying the nature of
problems and demands of the training for community leaders in the
upper northeastern region of Thailand. Population and group
samplings are based on 360 community leaders in the region who
have experienced prior training from the Udonthani Rajabhat
University. Stratified random samplings have been drawn upon 186
participants. The research tools is questionnaires. The frequency,
percentage and standard deviation are employed in data analysis. The
findings indicate that most of community leaders are males and
senior adults. The problems in training are associated with the
inconveniences of long-distance travelling to training locations,
inadequacy of learning centers and training sites and high training
costs. The demand of training is basically motivated by a desire for
self-development in modern knowledge in keeping up-to-date with
the changing world and the need for technological application and
facilitation in shortening the distance to training locations and in
limiting expensive training costs.
Abstract: A numerical study has been conducted to investigate the influence of fin pitch and relative humidity on the heat transfer performance of the fin-and-tube heat exchangers having plain fin geometry under dehumidifying conditions. The analysis is done using the ratio between the heat transfer coefficients in totally wet conditions and those in totally dry conditions using the appropriate correlations for both dry and wet conditions. For a constant relative humidity, it is found that the heat transfer coefficient increases with the increase of the air frontal velocity. By contrast, the fin efficiency decreases when the face velocity is increased. Apparently, this phenomenon is attributed to the path of condensate drainage. For the influence of relative humidity, the results showed an increase in heat transfer performance and a decrease in wet fin efficiency when relative humidity increases. This is due to the higher amount of mass transfer encountered at higher relative humidity. However, it is found that the effect of fin pitch on the heat transfer performance depends strongly on the face velocity. At lower frontal velocity the heat transfer increases with fin pitch. Conversely, an increase in fin pitch gives lower heat transfer coefficients when air velocity is increased.
Abstract: This article is presented an experimental and modeling
study of a four-bed pressure swing adsorption process using
zeolite13X to provide oxygen-enriched air. The binary mixture N2/O2
(79/21 vol %) was used as a feed stream. The effects of purge/feed
ratio (P/F), adsorption pressure, cyclic time and product flow rate on
product purity and recovery under nonisothermal condition were
studied. The adsorption dynamics of process were determined using
a mathematical model incorporated mass and energy balances. A
Mathlab code using finite difference method was developed to solve
the set of coupled differential-algebraic equations, and the simulation
results are agreed well with experimental results.
Abstract: This paper examines the available experiment data for a copper bromide vapor laser (CuBr laser), emitting at two wavelengths - 510.6 and 578.2nm. Laser output power is estimated based on 10 independent input physical parameters. A classification and regression tree (CART) model is obtained which describes 97% of data. The resulting binary CART tree specifies which input parameters influence considerably each of the classification groups. This allows for a technical assessment that indicates which of these are the most significant for the manufacture and operation of the type of laser under consideration. The predicted values of the laser output power are also obtained depending on classification. This aids the design and development processes considerably.
Abstract: In this paper we study numerical methods for solving Sylvester matrix equations of the form AX +XBT +CDT = 0. A new projection method is proposed. The union of Krylov subspaces in A and its inverse and the union of Krylov subspaces in B and its inverse are used as the right and left projection subspaces, respectively. The Arnoldi-like process for constructing the orthonormal basis of the projection subspaces is outlined. We show that the approximate solution is an exact solution of a perturbed Sylvester matrix equation. Moreover, exact expression for the norm of residual is derived and results on finite termination and convergence are presented. Some numerical examples are presented to illustrate the effectiveness of the proposed method.
Abstract: This paper proposes an adaptive sliding mode
controller which combines adaptive control and sliding
mode control to control a nonlinear robotic manipulator
with uncertain parameters. We use an adaptive algorithm
based on the concept of sliding mode control to alleviate the
chattering phenomenon of control input. Adaptive laws are
developed to obtain the gain of switching input and the
boundary layer parameters. The stability and convergence
of the robotic manipulator control system are guaranteed
by applying the Lyapunov theorem. Simulation results
demonstrate that the chattering of control input can be
alleviated effectively. The proposed controller scheme can
assure robustness against a large class of uncertainties and
achieve good trajectory tracking performance.
Abstract: A graph G is fractional k-covered if for each edge e of
G, there exists a fractional k-factor h, such that h(e) = 1. If k = 2,
then a fractional k-covered graph is called a fractional 2-covered
graph. The binding number bind(G) is defined as follows,
bind(G) = min{|NG(X)|
|X|
: ├ÿ = X Ôèå V (G),NG(X) = V (G)}.
In this paper, it is proved that G is fractional 2-covered if δ(G) ≥ 4
and bind(G) > 5
3 .
Abstract: Web-based systems have become increasingly
important due to the fact that the Internet and the World Wide Web
have become ubiquitous, surpassing all other technological
developments in our history. The Internet and especially companies
websites has rapidly evolved in their scope and extent of use, from
being a little more than fixed advertising material, i.e. a "web
presences", which had no particular influence for the company's
business, to being one of the most essential parts of the company's
core business.
Traditional software engineering approaches with process models
such as, for example, CMM and Waterfall models, do not work very
well since web system development differs from traditional
development. The development differs in several ways, for example,
there is a large gap between traditional software engineering designs
and concepts and the low-level implementation model, many of the
web based system development activities are business oriented (for
example web application are sales-oriented, web application and
intranets are content-oriented) and not engineering-oriented.
This paper aims to introduce Increment Iterative extreme
Programming (IIXP) methodology for developing web based
systems. In difference to the other existence methodologies, this
methodology is combination of different traditional and modern
software engineering and web engineering principles.
Abstract: We present a preliminary x-ray study on human-hair
microstructures for a health-state indicator, in particular a cancer
case. As an uncomplicated and low-cost method of x-ray technique,
the human-hair microstructure was analyzed by wide-angle x-ray
diffractions (XRD) and small-angle x-ray scattering (SAXS). The
XRD measurements exhibited the simply reflections at the d-spacing
of 28 Å, 9.4 Å and 4.4 Å representing to the periodic distance of the
protein matrix of the human-hair macrofibrous and the diameter and
the repeated spacing of the polypeptide alpha helixes of the
photofibrils of the human-hair microfibrous, respectively. When
compared to the normal cases, the unhealthy cases including to the
breast- and ovarian-cancer cases obtained higher normalized ratios of
the x-ray diffracting peaks of 9.4 Å and 4.4 Å. This likely resulted
from the varied distributions of microstructures by a molecular
alteration. As an elemental analysis by x-ray fluorescence (XRF), the
normalized quantitative ratios of zinc(Zn)/calcium(Ca) and
iron(Fe)/calcium(Ca) were determined. Analogously, both Zn/Ca and
Fe/Ca ratios of the unhealthy cases were obtained higher than both of
the normal cases were. Combining the structural analysis by XRD
measurements and the elemental analysis by XRF measurements
exhibited that the modified fibrous microstructures of hair samples
were in relation to their altered elemental compositions. Therefore,
these microstructural and elemental analyses of hair samples will be
benefit to associate with a diagnosis of cancer and genetic diseases.
This functional method would lower a risk of such diseases by the
early diagnosis. However, the high-intensity x-ray source, the highresolution
x-ray detector, and more hair samples are necessarily
desired to develop this x-ray technique and the efficiency would be
enhanced by including the skin and fingernail samples with the
human-hair analysis.
Abstract: Pure phase gallosilicate nitrite sodalite has been synthesized in a single step by low temperature (373 oK) hydrothermal technique. The product obtained was characterized using a combination of techniques including X-ray powder diffraction, IR, Raman spectroscopy, SEM, MAS NMR spectroscopy as well as thermogravimetry. Sodalite with an ideal composition was obtained after synthesis at 3730K and seven days duration using alkaline medium. The structural features of the Na8[GaSiO4]6(NO2)2 sodalite were investigated by IR, MAS NMR spectroscopy of 29Si and 23Na nuclei and by Reitveld refinement of X-ray powder diffraction data. The crystal structure of this sodalite has been refined in the space group P 4 3n; with a cell parameter 8.98386Å, V= 726.9 Å, (Rwp= 0.077 and Rp=0.0537) and Si-O-Ga angle is found to be 132.920 . MAS NMR study confirms complete ordering of Si and Ga in the gallosilicate framework. The surface area of single entity with stoichiometry Na8[GaSiO4]6(NO2)2 was found to be 8.083 x10-15 cm2/g.
Abstract: In mammalian reproductive tract, the oviduct secretes
huge number of growth factors and cytokines that create an optimal
micro-environment for the initial stages of preimplantation embryos.
Secretion of these growth factors is stage-specific. Among them,
VEGF is a potent mitogen for vascular endothelium and stimulates
vascular permeability. Apart from angiogenesis, VEGF in the oviduct
may be involved in regulating the oocyte maturation and subsequent
developmental process during embryo production in vitro. In
experiment 1, to evaluate the effect of VEGF during IVM of porcine
COC and subsequent developmental ability after PA and SCNT. The
results from these experiments indicated that maturation rates among
the different VEGF concentrations were not significant different. In
experiment 2, total intracellular GSH concentrations of oocytes
matured with VEGF (5-50 ng/ml) were increased significantly
compared to a control and VEGF group (500 ng/ml). In experiment 3,
the blastocyst formation rates and total cell number per blastocyst
after parthenogenesis of oocytes matured with VEGF (5-50 ng/ml)
were increased significantly compared to a control and VEGF group
(500 ng/ml). Similarly, in experiment 4, the blastocyst formation rate
and total cell number per blastocyst after SCNT and IVF of oocytes
matured with VEGF (5 ng/ml) were significantly higher than that of
oocytes matured without VEGF group. In experiment 5, at 10 hour
after the onset of IVF, pronuclear formation rate was evaluated.
Monospermy was significantly higher in VEGF-matured oocytes than
in the control, and polyspermy and sperm penetration per oocyte
were significantly higher in the control group than in the VEGFmatured
oocytes. Supplementation with VEGF during IVM
significantly improved male pronuclear formation as compared with
the control. In experiment 6, type III cortical granule distribution in
oocytes was more common in VEGF-matured oocytes than in the
control. In conclusion, the present study suggested that
supplementation of VEGF during IVM may enhance the
developmental potential of porcine in vitro embryos through increase
of the intracellular GSH level, higher MPN formation and increased
fertilization rate as a consequence of an improved cytoplasmic
maturation.
Abstract: This paper presents a resonant-based read-out circuit for capacitive pressure sensors. The proposed read-out circuit consists of an LC oscillator and a counter. The circuit detects the capacitance changes of a capacitive pressure sensor by means of frequency shifts from its nominal operation frequency. The proposed circuit is designed in 0.18 m CMOS with an estimated power consumption of 43.1mW. Simulation results show that the circuit has a capacitive resolution of 8.06kHz/fF, which enables it for high resolution pressure detection.
Abstract: This paper develops a pedometer with a three-axis acceleration sensor that can be placed with any angle. The proposed pedometer measures the number of steps while users walk, jog or run. It can be worn on users’ waistband or placed within pocket or backpack. The work address to improve on the general pedometers, which can only be used in a single direction or can only count of steps without the continuous exercise judgment mechanism. Finally, experimental results confirm the superior performance of the proposed pedometer.
Abstract: The unanticipated destruct of more of the steel moment frames in Northridge earthquake, altered class of regard to the beamto- column connections in moment frames. Panel zone is one the significant part of joints which, it-s stiffness and rigidity has an important effect on the behavior and ductility of the frame. Specifically that behavior of panel zone has a very significant effect on the special moment frames. In this paper , meanwhile the relations for modeling of panel zone in frames are expressed , special moment frames with different spans and stories were studied in the way of performance-based design. The frames designed in according with Iranian steel building code. The effect of panel zone is also considered and in the case of non-existence of performance level, by changing in intimacies and parameter of panel zone, performance level is considered.
Abstract: A novel application of neural network approach to
fault classification and fault location of Medium voltage cables is
demonstrated in this paper. Different faults on a protected cable
should be classified and located correctly. This paper presents the use
of neural networks as a pattern classifier algorithm to perform these
tasks. The proposed scheme is insensitive to variation of different
parameters such as fault type, fault resistance, and fault inception
angle. Studies show that the proposed technique is able to offer high
accuracy in both of the fault classification and fault location tasks.