Abstract: In order to avoid self-collision of space manipulators
during operation process, a real-time detection method is proposed in
this paper. The manipulator is fitted into a cylinder-enveloping
surface, and then, a kind of detection algorithm of collision between
cylinders is analyzed. The collision model of space manipulator
self-links can be detected by using this algorithm in real-time detection
during the operation process. To ensure security of the operation, a
safety threshold is designed. The simulation and experiment results
verify the effectiveness of the proposed algorithm for a 7-DOF space
manipulator.
Abstract: Design concepts of real-time embedded system can be
realized initially by introducing novel design approaches. In this
literature, model based design approach and in-the-loop testing were
employed early in the conceptual and preliminary phase to formulate
design requirements and perform quick real-time verification. The
design and analysis methodology includes simulation analysis, model
based testing, and in-the-loop testing. The design of conceptual driveby-
wire, or DBW, algorithm for electronic control unit, or ECU, was
presented to demonstrate the conceptual design process, analysis, and
functionality evaluation. The concepts of DBW ECU function can be
implemented in the vehicle system to improve electric vehicle, or EV,
conversion drivability. However, within a new development process,
conceptual ECU functions and parameters are needed to be evaluated.
As a result, the testing system was employed to support conceptual
DBW ECU functions evaluation. For the current setup, the system
components were consisted of actual DBW ECU hardware, electric
vehicle models, and control area network or CAN protocol. The
vehicle models and CAN bus interface were both implemented as
real-time applications where ECU and CAN protocol functionality
were verified according to the design requirements. The proposed
system could potentially benefit in performing rapid real-time
analysis of design parameters for conceptual system or software
algorithm development.
Abstract: In this research numerical simulations are performed,
using the multi-relaxation-time lattice Boltzmann method, in the
range 3 ≤ β = w[d] ≤ 30 at Re = 100, 200 and 300, where β the
blockage ratio, w is the equispaced distance between centers of
cylinders, d is the diameter of the cylinder and Re is the Reynolds
number, respectively. Special attention is paid to the effect of the
equispaced distance between centers of cylinders. Visualization of
the vorticity contour visualization are presented for some simulation
showing the flow dynamics and patterns for blockage effect. Results
show that the drag and mean drag coefficients, and Strouhal number,
in general, decrease with the increase of β for fixed Re. It is found
that the decreasing rate of drag and mean drag coefficients and
Strouhal number is more distinct in the range 3 ≤ β ≤ 15. We found
that when β > 15, the blockage effect almost diminishes. Our results
further indicate that the drag and mean drag coefficients, peak value
of the lift coefficient, root-mean-square value of the lift and drag
coefficients and the ratio between lift and drag coefficients decrease
with the increase of Re. The results indicate that symmetry boundary
condition have more blockage effect as compared to periodic
boundary condition.
Abstract: This study investigates the use of a time-series of
MODIS NDVI data to identify agricultural land cover change on an
annual time step (2007 - 2012) and characterize the trend. Following
an ISODATA classification of the MODIS imagery to selectively
mask areas not agriculture or semi-natural, NDVI signatures were
created to identify areas cereals and vineyards with the aid of
ancillary, pictometry and field sample data for 2010. The NDVI
signature curve and training samples were used to create a decision
tree model in WEKA 3.6.9 using decision tree classifier (J48)
algorithm; Model 1 including ISODATA classification and Model 2
not. These two models were then used to classify all data for the
study area for 2010, producing land cover maps with classification
accuracies of 77% and 80% for Model 1 and 2 respectively. Model 2
was subsequently used to create land cover classification and change
detection maps for all other years. Subtle changes and areas of
consistency (unchanged) were observed in the agricultural classes
and crop practices. Over the years as predicted by the land cover
classification. Forty one percent of the catchment comprised of
cereals with 35% possibly following a crop rotation system.
Vineyards largely remained constant with only one percent
conversion to vineyard from other land cover classes.
Abstract: Corrosion of concrete sewer pipes induced by
sulphuric acid attack is a recognised problem worldwide, which is not
only an attribute of countries with hot climate conditions as thought
before. The significance of this problem is by far only realised when
the pipe collapses causing surface flooding and other severe
consequences. To change the existing post-reactive attitude of
managing companies, easy to use and robust models are required to
be developed which currently lack reliable data to be correctly
calibrated. This paper focuses on laboratory experiments of
establishing concrete pipe corrosion rate by submerging samples in to
0.5pH sulphuric acid solution for 56 days under 10ºC, 20ºC and 30ºC
temperature regimes. The result showed that at very early stage of the
corrosion process the samples gained overall mass, at 30ºC the
corrosion progressed quicker than for other temperature regimes,
however with time the corrosion level for 10ºC and 20ºC regimes
tended towards those at 30ºC. Overall, at these conditions the
corrosion rates of 10 mm/year, 13,5 mm/year and 17 mm/year were
observed.
Abstract: We evaluate the performance of a numerical method
for global optimization of expensive functions. The method is using a
response surface to guide the search for the global optimum. This
metamodel could be based on radial basis functions, kriging, or a
combination of different models. We discuss how to set the cyclic
parameters of the optimization method to get a balance between local
and global search. We also discuss the eventual problem with Runge
oscillations in the response surface.
Abstract: Rehabilitation of dam components such as foundations, buttresses, spillways and overtopping protection require a wide range of construction and design methodologies. Geotechnical Engineering considerations play an important role in the design and construction of foundations of new dams. Much investigation is required to assess and evaluate the existing dams. The application of roller compacting concrete (RCC) has been accepted as a new method for constructing new dams or rehabilitating old ones. In the past 40 years there have been so many changes in the usage of RCC and now it is one of most satisfactory solutions of water and hydropower resource throughout the world. The considerations of rehabilitation and construction of dams might differ due to upstream reservoir and its influence on penetrating and dewatering of downstream, operations requirements and plant layout. One of the advantages of RCC is its rapid placement which allows the dam to be operated quickly. Unlike ordinary concrete it is a drier mix, and stiffs enough for compacting by vibratory rollers. This paper evaluates some different aspects of RCC and focuses on its preparation progress.
Abstract: An adaptive nonparametric method is proposed for
stable real-time detection of seismoacoustic sources in multichannel
C-OTDR systems with a significant number of channels. This
method guarantees given upper boundaries for probabilities of Type I
and Type II errors. Properties of the proposed method are rigorously
proved. The results of practical applications of the proposed method
in a real C-OTDR-system are presented in this report.
Abstract: Cloud computing is the innovative and leading
information technology model for enabling convenient, on-demand
network access to a shared pool of configurable computing resources
that can be rapidly provisioned and released with minimal
management effort. In this paper, we aim at the development of
workflow management system for cloud computing platforms based
on our previous research on the dynamic allocation of the cloud
computing resources and its workflow process. We took advantage of
the HTML5 technology and developed web-based workflow interface.
In order to enable the combination of many tasks running on the cloud
platform in sequence, we designed a mechanism and developed an
execution engine for workflow management on clouds. We also
established a prediction model which was integrated with job queuing
system to estimate the waiting time and cost of the individual tasks on
different computing nodes, therefore helping users achieve maximum
performance at lowest payment. This proposed effort has the potential
to positively provide an efficient, resilience and elastic environment
for cloud computing platform. This development also helps boost user
productivity by promoting a flexible workflow interface that lets users
design and control their tasks' flow from anywhere.
Abstract: The present paper presents the discussion of scholars
concerning speech impact, peculiarities of its realization, speech
strategies and techniques in particular. Departing from the viewpoints
of many prominent linguists, the paper suggests that manipulative
argumentation be viewed as a most pervasive speech strategy with a
certain set of techniques which are to be found in modern American
political discourse. The precedence of their occurrence allows us to
regard them as pragmatic patterns of speech impact realization in
effective public speaking.
Abstract: Agro-industry is one of major industries that have
strong impacts on national economic incomes, growth, stability, and
sustainable development. Moreover, this industry also has strong
influences on social, cultural and political issues. Furthermore, this
industry, as producing primary and secondary products, is facing
challenges from such diverse factors such as demand inconsistency,
intense international competition, technological advancements and
new competitors. In order to maintain and to improve industry’s
competitiveness in both domestics and international markets, science
and technology are key factors. Besides hard sciences and
technologies, modern industrial engineering concepts such as Just in
Time (JIT) Total Quality Management (TQM), Quick Response
(QR), Supply Chain Management (SCM) and Lean can be very
effective to support to increase efficiency and effectiveness of these
agricultural products on world stage. Onion is one of Thailand’s
major export products which bring back national incomes. But, it is
also facing challenges in many ways. This paper focused its interests
in onion packing process and its related activities such as storage and
shipment from one of major packing plant and storage in Mae Wang
District, Chiang Mai, Thailand, by applying Toyota Production
System (TPS) or Lean concepts, to improve process capability
throughout the entire packing and distribution process which will be
profitable for the whole onion supply chain. And it will be beneficial
to other related agricultural products in Thailand and other ASEAN
countries.
Abstract: This work is the first dowel in a rather wide research
activity in collaboration with Euro Mediterranean Center for Climate
Changes, aimed at introducing scalable approaches in Ocean
Circulation Models. We discuss designing and implementation of
a parallel algorithm for solving the Variational Data Assimilation
(DA) problem on Graphics Processing Units (GPUs). The algorithm
is based on the fully scalable 3DVar DA model, previously proposed
by the authors, which uses a Domain Decomposition approach
(we refer to this model as the DD-DA model). We proceed with
an incremental porting process consisting of 3 distinct stages:
requirements and source code analysis, incremental development of
CUDA kernels, testing and optimization. Experiments confirm the
theoretic performance analysis based on the so-called scale up factor
demonstrating that the DD-DA model can be suitably mapped on
GPU architectures.
Abstract: Roadway planning and design is a very complex
process involving five key phases before a project is completed;
planning, project development, final design, right-of-way, and
construction. The planning phase for a new roadway transportation
project is a very critical phase as it greatly affects all latter phases of
the project. A location study is usually performed during the
preliminary planning phase in a new roadway project. The objective
of the location study is to develop alignment alternatives that are cost
efficient considering land acquisition and construction costs. This
paper describes a methodology to develop optimal preliminary
roadway alignments utilizing spatial-data. Four optimization criteria
are taken into consideration; roadway length, land cost, land slope,
and environmental impacts. The basic concept of the methodology is
to convert the proposed project area into a grid, which represents the
search space for an optimal alignment. The aforementioned
optimization criteria are represented in each of the grid’s cells. A
spatial-data optimization technique is utilized to find the optimal
alignment in the search space based on the four optimization criteria.
Two case studies for new roadway projects in Duval County in the
State of Florida are presented to illustrate the methodology. The
optimization output alignments are compared to the proposed Florida
Department of Transportation (FDOT) alignments. The comparison is
based on right-of-way costs for the alignments. For both case studies,
the right-of-way costs for the developed optimal alignments were
found to be significantly lower than the FDOT alignments.
Abstract: The structures obtained with the use of sandwich
technologies combine low weight with high energy absorbing
capacity and load carrying capacity. Hence, there is a growing and
markedly interest in the use of sandwiches with aluminum foam core
because of very good properties such as flexural rigidity and energy
absorption capability. In the current investigation, the static threepoint
bending tests were carried out on the sandwiches with
aluminum foam core and glass fiber reinforced polymer (GFRP)
skins at different values of support span distances aiming the analyses
of their flexural performance. The influence of the core thickness and
the GFRP skin type was reported in terms of peak load and energy
absorption capacity. For this purpose, the skins with two different
types of fabrics which have same thickness value and the aluminum
foam core with two different thicknesses were bonded with a
commercial polyurethane based flexible adhesive in order to combine
the composite sandwich panels. The main results of the bending tests
are: force-displacement curves, peak force values, absorbed energy,
collapse mechanisms and the effect of the support span length and
core thickness. The results of the experimental study showed that the
sandwich with the skins made of S-Glass Woven fabrics and with the
thicker foam core presented higher mechanical values such as load
carrying and energy absorption capacities. The increment of the
support span distance generated the decrease of the mechanical
values for each type of panels, as expected, because of the inverse
proportion between the force and span length. The most common
failure types of the sandwiches are debonding of the lower skin and
the core shear. The obtained results have particular importance for
applications that require lightweight structures with a high capacity
of energy dissipation, such as the transport industry (automotive,
aerospace, shipbuilding and marine industry), where the problems of
collision and crash have increased in the last years.
Abstract: The article presents two mathematical models of the
interaction between a rotating shaft and an incompressible fluid. The
mathematical model includes both the journal bearings and the
axially traversed hydrodynamic sealing gaps of hydraulic machines.
A method is shown for the identification of additional effects of the
fluid acting on the rotor of the machine, both for a linear and a nonlinear
model. The interaction is expressed by matrices of mass,
stiffness and damping.
Abstract: The potential neuroprotective effect of Phyllantus
nuriri against Fe2+ and sodium nitroprusside (SNP) induced oxidative
stress in mitochondria of rats brain was evaluated. Cellular viability
was assessed by MTT reduction, reactive oxygen species (ROS)
generation was measured using the probe 2,7-dichlorofluoresce
indiacetate (DCFH-DA). Glutathione content was measured using
dithionitrobenzoic acid (DTNB). Fe2+ (10μM) and SNP (5μM)
significantly decreased mitochondrial activity, assessed by MTT
reduction assay, in a dose-dependent manner, this occurred in parallel
with increased glutathione oxidation, ROS production and lipid
peroxidation end-products (thiobarbituric acid reactive substances,
TBARS). The co-incubation with methanolic extract of Phyllantus
nuriri (10-200 μg/ml) reduced the disruption of mitochondrial
activity, gluthathione oxidation, ROS production as well as the
increase in TBARS levels caused by both Fe2+ and SNP in a dose
dependent manner. HPLC analysis of the extract revealed the
presence of gallic acid (20.540.01), caffeic acid (7.930.02), rutin
(25.310.05), quercetin (31.280.03) and kaemferol (14.360.01).
This result suggests that these phytochemicals account for the
protective actions of P. niruri against Fe2+ and SNP -induced
oxidative stress. Our results show that P. nuriri consist important
bioactive molecules in the search for an improved therapy against the
deleterious effects of Fe2+, an intrinsic producer of reactive oxygen
species (ROS), that leads to neuronal oxidative stress and
neurodegeneration.
Abstract: Latin hypercube designs (LHDs) have been applied in
many computer experiments among the space-filling designs found in
the literature. A LHD can be randomly generated but a randomly
chosen LHD may have bad properties and thus act poorly in
estimation and prediction. There is a connection between Latin
squares and orthogonal arrays (OAs). A Latin square of order s
involves an arrangement of s symbols in s rows and s columns, such
that every symbol occurs once in each row and once in each column
and this exists for every non-negative integer s. In this paper, a
computer program was written to construct orthogonal array-based
Latin hypercube designs (OA-LHDs). Orthogonal arrays (OAs) were
constructed from Latin square of order s and the OAs constructed
were afterward used to construct the desired Latin hypercube designs
for three input variables for use in computer experiments. The LHDs
constructed have better space-filling properties and they can be used
in computer experiments that involve only three input factors.
MATLAB 2012a computer package (www.mathworks.com/) was
used for the development of the program that constructs the designs.
Abstract: One of the main challenges in using the Discrete
Element Method (DEM) is to specify the correct input parameter
values. In general, the models are sensitive to the input parameter
values and accurate results can only be achieved if the correct values
are specified. For the linear contact model, micro-parameters such as
the particle density, stiffness, coefficient of friction, as well as the
particle size and shape distributions are required. There is a need for
a procedure to accurately calibrate these parameters before any
attempt can be made to accurately model a complete bulk materials
handling system. Since DEM is often used to model applications in
the mining and quarrying industries, a calibration procedure was
developed for materials that consist of relatively large (up to 40 mm
in size) particles. A coarse crushed aggregate was used as the test
material. Using a specially designed large shear box with a diameter
of 590 mm, the confined Young’s modulus (bulk stiffness) and
internal friction angle of the material were measured by means of the
confined compression test and the direct shear test respectively. DEM
models of the experimental setup were developed and the input
parameter values were varied iteratively until a close correlation
between the experimental and numerical results was achieved. The
calibration process was validated by modelling the pull-out of an
anchor from a bed of material. The model results compared well with
experimental measurement.
Abstract: Icons, or pictorial and graphical objects, are
commonly used in human-computer interaction (HCI) fields as the
mediator in order to communicate information to users. Yet there has
been little studies focusing on a majority of the world’s population –
semi-literate communities – in terms of the fundamental knowhow
for designing icons for such population. In this study, two sets of
icons belonging in different icon taxonomy – abstract and concrete –
are designed for a mobile application for semi-literate agricultural
communities. In this paper, we propose a triadic relationship of an
icon, namely meaning, task and mental image, which inherits the
triadic relationship of a sign. User testing with the application and a
post-pilot questionnaire are conducted as the experimental approach
in two rural villages in India. Icons belonging to concrete taxonomy
perform better than abstract icons on the premise that the design of
the icon fulfills the underlying rules of the proposed triadic
relationship.
Abstract: An experimental and analytical research on shear
buckling of a comparably large polymer composite I-section is
presented. It is known that shear buckling load of a large span
composite beam is difficult to determine experimentally. In order to
sensitively detect shear buckling of the tested I-section, twenty strain
rosettes and eight displacement sensors were applied and attached on
the web and flange surfaces. The tested specimen was a pultruded
composite beam made of vinylester resin, E-glass, carbon fibers and
micro-fillers. Various coupon tests were performed before the shear
buckling test to obtain fundamental material properties of the Isection.
An asymmetric four-point bending loading scheme was
utilized for the shear test. The loading scheme resulted in a high shear
and almost zero moment condition at the center of the web panel. The
shear buckling load was successfully determined after analyzing the
obtained test data from strain rosettes and displacement sensors. An
analytical approach was also performed to verify the experimental
results and to support the discussed experimental program.