Abstract: System development life cycle (SDLC) is a
process uses during the development of any system. SDLC
consists of four main phases: analysis, design, implement and
testing. During analysis phase, context diagram and data flow
diagrams are used to produce the process model of a system.
A consistency of the context diagram to lower-level data flow
diagrams is very important in smoothing up developing
process of a system. However, manual consistency check from
context diagram to lower-level data flow diagrams by using a
checklist is time-consuming process. At the same time, the
limitation of human ability to validate the errors is one of the
factors that influence the correctness and balancing of the
diagrams. This paper presents a tool that automates the
consistency check between Data Flow Diagrams (DFDs)
based on the rules of DFDs. The tool serves two purposes: as
an editor to draw the diagrams and as a checker to check the
correctness of the diagrams drawn. The consistency check
from context diagram to lower-level data flow diagrams is
embedded inside the tool to overcome the manual checking
problem.
Abstract: Most papers model Joint Replenishment Problem
(JRP) as a (kT,S) where kT is a multiple value for a common review
period T,and S is a predefined order up to level. In general the (T,S)
policy is characterized by a long out of control period which requires
a large amount of safety stock compared to the (R,Q) policy. In this
paper a probabilistic model is built where an item, call it item(i),
with the shortest order time between interval (T)is modeled under
(R,Q) policy and its inventory is continuously reviewed, while the
rest of items (j) are periodically reviewed at a definite time
corresponding to item
Abstract: The performance of high-resolution schemes is investigated for unsteady, inviscid and compressible multiphase flows. An Eulerian diffuse interface approach has been chosen for the simulation of multicomponent flow problems. The reduced fiveequation and seven equation models are used with HLL and HLLC approximation. The authors demonstrated the advantages and disadvantages of both seven equations and five equations models studying their performance with HLL and HLLC algorithms on simple test case. The seven equation model is based on two pressure, two velocity concept of Baer–Nunziato [10], while five equation model is based on the mixture velocity and pressure. The numerical evaluations of two variants of Riemann solvers have been conducted for the classical one-dimensional air-water shock tube and compared with analytical solution for error analysis.
Abstract: Because of high ductility, aluminum alloys, have been widely used as an important base of metal forming industries. But the main week point of these alloys is their low strength so in forming them with conventional methods like deep drawing, hydro forming, etc have been always faced with problems like fracture during of forming process. Because of this, recently using of explosive forming method for forming of these plates has been recommended. In this paper free explosive forming of A2024 aluminum alloy is numerically simulated and during it, explosion wave propagation process is studied. Consequences of this simulation can be effective in prediction of quality of production. These consequences are compared with an experimental test and show the superiority of this method to similar methods like hydro forming and deep drawing.
Abstract: Software development has experienced remarkable progress in the past decade. However, due to the rising complexity and magnitude of the project the development productivity has not been consistently improved. By analyzing the latest ISBSG data repository with 4106 projects, we discovered that software development productivity has actually undergone irregular variations between the years 1995 and 2005. Considering the factors significant to the productivity, we found its variations are primarily caused by the variations of average team size and the unbalanced uses of the less productive language 3GL.
Abstract: In this paper, we use Radial Basis Function Networks
(RBFN) for solving the problem of environmental interference
cancellation of speech signal. We show that the Second Order Thin-
Plate Spline (SOTPS) kernel cancels the interferences effectively.
For make comparison, we test our experiments on two conventional
most used RBFN kernels: the Gaussian and First order TPS (FOTPS)
basis functions. The speech signals used here were taken from the
OGI Multi-Language Telephone Speech Corpus database and were
corrupted with six type of environmental noise from NOISEX-92
database. Experimental results show that the SOTPS kernel can
considerably outperform the Gaussian and FOTPS functions on
speech interference cancellation problem.
Abstract: In the paper we discuss the influence of the route
flexibility degree, the open rate of operations and the production type
coefficient on makespan. The flexible job-open shop scheduling
problem FJOSP (an extension of the classical job shop scheduling) is
analyzed. For the analysis of the production process we used a
hybrid heuristic of the GRASP (greedy randomized adaptive search
procedure) with simulated annealing algorithm. Experiments with
different levels of factors have been considered and compared. The
GRASP+SA algorithm has been tested and illustrated with results for
the serial route and the parallel one.
Abstract: Impurity metals such as manganese and cadmium
from high-tenor cobalt electrolyte solution were selectively removed
by solvent extraction method using Co-D2EHPA after converting the functional group of D2EHPA with Co2+ ions. The process parameters
such as pH, organic concentration, O/A ratio, kinetics etc. were
investigated and the experiments were conducted by batch tests in the laboratory bench scale. Results showed that a significant amount
of manganese and cadmium can be extracted using Co-D2EHPA for the optimum processing of cobalt electrolyte solution at equilibrium pH about 3.5. The McCabe-Thiele diagram, constructed from the
extraction studies showed that 100% impurities can be extracted through four stages for manganese and three stages for cadmium
using O/A ratio of 0.65 and 1.0, respectively. From the stripping study, it was found that 100% manganese and cadmium can be stripped from the loaded organic using 0.4 M H2SO4 in a single
contact. The loading capacity of Co-D2EHPA by manganese and cadmium were also investigated with different O/A ratio as well as
with number of stages of contact of aqueous and organic phases. Valuable information was obtained for the designing of an impurities
removal process for the production of pure cobalt with less trouble in the electrowinning circuit.
Abstract: Composite pins of rubber dust collected from tyre
retreading centres of trucks, cars and buses etc.and epoxy with
weight percentages of 10. 15, and 20 % of rubber (weight fractions of
9, 13 and 17 % respectively) have been prepared in house with the
help of a split wooden mould. The pins were tested in a pin-on-disc
wear monitor to determine the co-efficient of friction and weight
losses with varying speeds, loads and time. The wear volume and
wear rates have also been found out for all these three specimens.. It
is observed that all the specimens have exhibited very low coefficient
of friction and low wear rates under dry sliding condition. Out of the
above three samples tested, the specimen with 10 % rubber dust by
weight has shown lowest wear rates. However a peculiar result i.e
decreasing trend has been obtained with 20% reinforcement of rubber
in epoxy while rubbed against steel at varying speeds. This might
have occurred due to high surface finish of the disc and formation of
a thin transfer layer from the composite
Abstract: It is well known that the channel capacity of Multiple-
Input-Multiple-Output (MIMO) system increases as the number of
antenna pairs between transmitter and receiver increases but it suffers
from multiple expensive RF chains. To reduce the cost of RF chains,
Antenna Selection (AS) method can offer a good tradeoff between
expense and performance. In a transmitting AS system, Channel
State Information (CSI) feedback is necessarily required to choose
the best subset of antennas in which the effects of delays and errors
occurred in feedback channels are the most dominant factors
degrading the performance of the AS method. This paper presents the
concept of AS method using CSI from channel reciprocity instead of
feedback method. Reciprocity technique can easily archive CSI by
utilizing a reverse channel where the forward and reverse channels
are symmetrically considered in time, frequency and location. In this
work, the capacity performance of MIMO system when using AS
method at transmitter with reciprocity channels is investigated by
own developing Testbed. The obtained results show that reciprocity
technique offers capacity close to a system with a perfect CSI and
gains a higher capacity than a system without AS method from 0.9 to
2.2 bps/Hz at SNR 10 dB.
Abstract: This paper aimed to study the factors that relate to
working behavior of employees at Pakkred Municipality, Nonthaburi
Province. A questionnaire was utilized as the tool in collecting
information. Descriptive statistics included frequency, percentage,
mean and standard deviation. Independent- sample t- test, analysis of
variance and Pearson Correlation were also used. The findings of this
research revealed that the majority of the respondents were female,
between 25- 35 years old, married, with a Bachelor degree. The
average monthly salary of respondents was between 8,001- 12,000
Baht, and having about 4-7 years of working experience. Regarding
the overall working motivation factors, the findings showed that
interrelationship, respect, and acceptance were ranked as highly
important factors, whereas motivation, remunerations & welfare,
career growth, and working conditions were ranked as moderately
important factors. Also, overall working behavior was ranked as high.
The hypotheses testing revealed that different genders had a
different working behavior and had a different way of working as a
team, which was significant at the 0.05 confidence level, Moreover,
there was a difference among employees with different monthly
salary in working behavior, problem- solving and decision making,
which all were significant at the 0.05 confidence level. Employees
with different years of working experience were found to have work
working behavior both individual and as a team at the statistical
significance level of 0.01 and 0.05. The result of testing the
relationship between motivation in overall working revealed that
interrelationship, respect and acceptance from others, career growth,
and working conditions related to working behavior at a moderate
level, while motivation in performing duties and remunerations and
welfares related to working behavior towards the same direction at a
low level, with a statistical significance of 0.01.
Abstract: Springback is a significant problem in the sheet metal
forming process. When the tools are released after the stage of
forming, the product springs out, because of the action of the internal
stresses. In many cases the deviation of form is too large and the
compensation of the springback is necessary. The precise prediction
of the springback of product is increasingly significant for the design
of the tools and for compensation because of the higher ratio of the
yield stress to the elastic modulus.
The main object in this paper was to study the effect of the
anisotropy on the springback for three directions of rolling: 0°, 45°
and 90°. At the same time, we highlighted the influence of three
different metallic materials: Aluminum, Steel and Galvanized steel.
The original of our purpose consist on tests which are ensured by
adapting a U-type stretching-bending device on a tensile testing
machine, where we studied and quantified the variation of the
springback according to the direction of rolling. We also showed the
role of lubrication in the reduction of the springback.
Moreover, in this work, we have studied important characteristics
in deep drawing process which is a springback. We have presented
defaults that are showed in this process and many parameters
influenced a springback.
Finally, our results works lead us to understand the influence of
grains orientation with different metallic materials on the springback
and drawing some conclusions how to concept deep drawing tools. In
addition, the conducted work represents a fundamental contribution
in the discussion the industry application.
Abstract: Traditionally, Internet has provided best-effort service to every user regardless of its requirements. However, as Internet becomes universally available, users demand more bandwidth and applications require more and more resources, and interest has developed in having the Internet provide some degree of Quality of Service. Although QoS is an important issue, the question of how it will be brought into the Internet has not been solved yet. Researches, due to the rapid advances in technology are proposing new and more desirable capabilities for the next generation of IP infrastructures. But neither all applications demand the same amount of resources, nor all users are service providers. In this way, this paper is the first of a series of papers that presents an architecture as a first step to the optimization of QoS in the Internet environment as a solution to a SMSE's problem whose objective is to provide public service to internet with certain Quality of Service expectations. The service provides new business opportunities, but also presents new challenges. We have designed and implemented a scalable service framework that supports adaptive bandwidth based on user demands, and the billing based on usage and on QoS. The developed application has been evaluated and the results show that traffic limiting works at optimum and so it does exceeding bandwidth distribution. However, some considerations are done and currently research is under way in two basic areas: (i) development and testing new transfer protocols, and (ii) developing new strategies for traffic improvements based on service differentiation.
Abstract: Isobaric vapor-liquid equilibrium measurements are reported for the binary mixtures of n-Butylamine and Triethylamine with Cumene at 97.3 kPa. The measurements have been performed using a vapor recirculating type (modified Othmer's) equilibrium still. The binary mixture of n-Butylamine + Cumene shows positive deviation from ideality. Triethylamine + Cumene mixture shows negligible deviation from ideality. None of the systems form an azeotrope. The activity coefficients have been calculated taking into consideration the vapor phase nonideality. The data satisfy the thermodynamic consistency test of Herington. The activity coefficients have been satisfactorily correlated by means of the Margules, NRTL, and Black equations. The activity coefficient values obtained by the UNIFAC model are also reported.
Abstract: IEEE 802.16 is a new wireless technology standard, it
has some advantages, including wider coverage, higher bandwidth,
and QoS support. As the new wireless technology for last mile
solution, there are designed two models in IEEE 802.16 standard. One
is PMP (point to multipoint) and the other is Mesh. In this paper we
only focus on IEEE 802.16 Mesh model. According to the IEEE
802.16 standard description, Mesh model has two scheduling modes,
centralized and distributed. Considering the pros and cons of the two
scheduling, we present the combined scheduling QoS framework that
the BS (Base Station) controls time frame scheduling and selects the
shortest path from source to destination directly. On the other hand, we
propose the Expedited Queue mechanism to cut down the transmission
time. The EQ mechanism can reduce a lot of end-to-end delay in our
QoS framework. Simulation study has shown that the average delay is
smaller than contrasts. Furthermore, our proposed scheme can also
achieve higher performance.
Abstract: This paper presents a solution for the behavioural
animation of autonomous virtual agent navigation in virtual environments.
We focus on using Dempster-Shafer-s Theory of Evidence
in developing visual sensor for virtual agent. The role of the visual
sensor is to capture the information about the virtual environment
or identifie which part of an obstacle can be seen from the position
of the virtual agent. This information is require for vitual agent to
coordinate navigation in virtual environment. The virual agent uses
fuzzy controller as a navigation system and Fuzzy α - level for
the action selection method. The result clearly demonstrates the path
produced is reasonably smooth even though there is some sharp turn
and also still not diverted too far from the potential shortest path.
This had indicated the benefit of our method, where more reliable
and accurate paths produced during navigation task.
Abstract: In non destructive testing by radiography, a perfect
knowledge of the weld defect shape is an essential step to
appreciate the quality of the weld and make decision on its
acceptability or rejection. Because of the complex nature of the
considered images, and in order that the detected defect region
represents the most accurately possible the real defect, the choice
of thresholding methods must be done judiciously. In this paper,
performance criteria are used to conduct a comparative study of
four non parametric histogram thresholding methods for automatic
extraction of weld defect in radiographic images.
Abstract: The objective of current study is to investigate the
differences of winning and losing teams in terms of goal scoring and
passing sequences. Total of 31 matches from UEFA-EURO 2012
were analyzed and 5 matches were excluded from analysis due to
matches end up drawn. There are two groups of variable used in the
study which is; i. the goal scoring variable and: ii. passing sequences
variable. Data were analyzed using Wilcoxon matched pair rank test
with significant value set at p < 0.05. Current study found the timing
of goal scored was significantly higher for winning team at 1st half
(Z=-3.416, p=.001) and 2nd half (Z=-3.252, p=.001). The scoring
frequency was also found to be increase as time progressed and the
last 15 minutes of the game was the time interval the most goals
scored. The indicators that were significantly differences between
winning and losing team were the goal scored (Z=-4.578, p=.000),
the head (Z=-2.500, p=.012), the right foot (Z=-3.788,p=.000),
corner (Z=-.2.126,p=.033), open play (Z=-3.744,p=.000), inside the
penalty box (Z=-4.174, p=.000) , attackers (Z=-2.976, p=.003) and
also the midfielders (Z=-3.400, p=.001). Regarding the passing
sequences, there are significance difference between both teams in
short passing sequences (Z=-.4.141, p=.000). While for the long
passing, there were no significance difference (Z=-.1.795, p=.073).
The data gathered in present study can be used by the coaches to
construct detailed training program based on their objectives.
Abstract: Use of a sliding joint is an effective method to
decrease the stress in foundation structure where there is a horizontal
deformation of subsoil (areas afflicted with underground mining) or
horizontal deformation of a foundation structure (pre-stressed
foundations, creep, shrinkage, temperature deformation). A
convenient material for a sliding joint is a bitumen asphalt belt.
Experiments for different types of bitumen belts were undertaken at
the Faculty of Civil Engineering - VSB Technical University of
Ostrava in 2008. This year an extension of the 2008 experiments is in
progress and the shear resistance of a slide joint is being tested as a
function of temperature in a temperature controlled room. In this
paper experimental results of temperature dependant shear resistance
are presented. The result of the experiments should be the sliding
joint shear resistance as a function of deformation velocity and
temperature. This relationship is used for numerical analysis of
stress/strain relation between foundation structure and subsoil. Using
a rheological slide joint could lead to a decrease of the reinforcement
amount, and contribute to higher reliability of foundation structure
and thus enable design of more durable and sustainable building
structures.
Abstract: This paper describes Nano-particle based Planar Laser
Scattering (NPLS) flow visualization of angled supersonic jets into a
supersonic cross flow based on the HYpersonic Low TEmperature
(HYLTE) nozzle which was widely used in DF chemical laser. In
order to investigate the non-reacting flowfield in the HYLTE nozzle, a
testing section with windows was designed and manufactured. The
impact of secondary fluids orifice separation on mixing was examined.
For narrow separation of orifices, the secondary fuel penetration
increased obviously compared to diluent injection, which means
smaller separation of diluent and fuel orifices would enhance the
mixing of fuel and oxidant. Secondary injections with angles of 30, 40
and 50 degrees were studied. It was found that the injectant
penetration increased as the injection angle increased, while the
interfacial surface area to entrain the freestream fluid is largest when
the injection angle is 40 degree.