Abstract: This study investigates the effects of the lead angle
and chip thickness variation on surface roughness during the
machining of compacted graphite iron using ceramic cutting tools
under dry cutting conditions. Analytical models were developed for
predicting the surface roughness values of the specimens after the
face milling process. Experimental data was collected and imported
to the artificial neural network model. A multilayer perceptron model
was used with the back propagation algorithm employing the input
parameters of lead angle, cutting speed and feed rate in connection
with chip thickness. Furthermore, analysis of variance was employed
to determine the effects of the cutting parameters on surface
roughness. Artificial neural network and regression analysis were
used to predict surface roughness. The values thus predicted were
compared with the collected experimental data, and the
corresponding percentage error was computed. Analysis results
revealed that the lead angle is the dominant factor affecting surface
roughness. Experimental results indicated an improvement in the
surface roughness value with decreasing lead angle value from 88° to
45°.
Abstract: Waste Load Allocation (WLA) strategies usually
intend to find economic policies for water resource management.
Water quality trading (WQT) is an approach that uses discharge
permit market to reduce total environmental protection costs. This
primarily requires assigning discharge limits known as total
maximum daily loads (TMDLs). These are determined by monitoring
organizations with respect to the receiving water quality and
remediation capabilities. The purpose of this study is to compare two
approaches of TMDL assignment for WQT policy in small catchment
area of Haraz River, in north of Iran. At first, TMDLs are assigned
uniformly for the whole point sources to keep the concentrations of
BOD and dissolved oxygen (DO) at the standard level at checkpoint
(terminus point). This was simply simulated and controlled by
Qual2kw software. In the second scenario, TMDLs are assigned
using multi objective particle swarm optimization (MOPSO) method
in which the environmental violation at river basin and total treatment
costs are minimized simultaneously. In both scenarios, the equity
index and the WLA based on trading discharge permits (TDP) are
calculated. The comparative results showed that using economically
optimized TMDLs (2nd scenario) has slightly more cost savings rather
than uniform TMDL approach (1st scenario). The former annually
costs about 1 M$ while the latter is 1.15 M$. WQT can decrease
these annual costs to 0.9 and 1.1 M$, respectively. In other word,
these approaches may save 35 and 45% economically in comparison
with command and control policy. It means that using multi objective
decision support systems (DSS) may find more economical WLA,
however its outcome is not necessarily significant in comparison with
uniform TMDLs. This may be due to the similar impact factors of
dischargers in small catchments. Conversely, using uniform TMDLs
for WQT brings more equity that makes stakeholders not feel that
much envious of difference between TMDL and WQT allocation. In
addition, for this case, determination of TMDLs uniformly would be
much easier for monitoring. Consequently, uniform TMDL for TDP
market is recommended as a sustainable approach. However,
economical TMDLs can be used for larger watersheds.
Abstract: This work consists of a numerical simulation of
convective heat transfer in a vertical plane channel filled with a heat
generating porous medium, in the absence of local thermal
equilibrium. The walls are maintained to a constant temperature and
the inlet velocity is uniform. The dynamic range is described by the
Darcy-Brinkman model and the thermal field by two energy
equations model. A dimensionless formulation is developed for
performing a parametric study based on certain dimensionless groups
such as, the Biot interstitial number, the thermal conductivity ratio
and the volumetric heat generation, q '''. The governing equations are
solved using the finite volume method, gave rise to a multitude of
results concerning in particular the thermal field in the porous
channel and the existence or not of the local thermal equilibrium.
Abstract: Evidence shows that start-ups success is positively
correlated with the launch of the first product. However, new ventures
are seldom able to acquire abundant resources for new product
development (NPD), which means that entrepreneurs may depend on
personal creativity instead of physical investments to achieve and
accelerate innovation speed. This study accentuates the role of
entrepreneurial bricolage, which defined as making do by applying
combinations of the resources at hand to new problems and
opportunities, in the relations of creative self-efficacy and innovation
speed. This study uses the multiple regression analysis to test the
hypotheses in a sample of 203 start-ups operating in various creative
markets in Taiwan. Results reveal that creative self-efficacy is
positively and directly associated with innovation speed, whereas
entrepreneurial bricolage plays a full mediator. These findings offer
important theoretical and practical implications.
Abstract: We used live E. coli containing synthetic genetic
oscillators to study how the degree of synchrony between the genetic
circuits of sister cells changes with temperature. We found that both
the mean and the variability of the degree of synchrony between the
fluorescence signals from sister cells are affected by temperature.
Also, while most pairs of sister cells were found to be highly
synchronous in each condition, the number of asynchronous pairs
increased with increasing temperature, which was found to be due to
disruptions in the oscillations. Finally we provide evidence that these
disruptions tend to affect multiple generations as opposed to
individual cells. These findings provide insight in how to design
more robust synthetic circuits and in how cell division can affect their
dynamics.
Abstract: Background: Delayed onset muscle soreness (DOMS)
is the most common symptom when ordinary individuals and athletes
are exposed to unaccustomed physical activity, especially eccentric
contraction which impairs athletic performance, ordinary people
work ability and physical functioning. Multitudes of methods have
been investigated to reduce DOMS. One of the valuable methods to
control DOMS is repeated bout effect (RBE) as a prophylactic
method. Purpose: To compare the repeated bout effect of
submaximal eccentric with maximal isometric contraction on induced
DOMS. Methods: Sixty normal male volunteers were assigned
randomly into three equal groups: Group A (first study group): 20
subjects received submaximal eccentric contraction on non-dominant
elbow flexors as a prophylactic exercise. Group B (second study
group): 20 subjects received maximal isometric contraction on nondominant
elbow flexors as a prophylactic exercise. Group C (control
group): 20 subjects did not receive any prophylactic exercises.
Maximal isometric peak torque of elbow flexors and patient related
elbow evaluation (PREE) scale were measured for each subject 3
times before, immediately after, and 48 hours after induction of
DOMS. Results: Post-hoc test for maximal isometric peak torque and
PREE scale immediately and 48 hours after induction of DOMS
revealed that group (A) and group (B) resulted in significant decrease
in maximal isometric strength loss and elbow pain and disability
rather than control group (C), but submaximal eccentric group (A)
was more effective than maximal isometric group (B) as it showed
more rapid recovery of functional strength and less degrees of elbow
pain and disability. Conclusion: Both submaximal eccentric
contraction and maximal isometric contraction were effective in
prevention of DOMS but submaximal eccentric contraction produced
a greater protective effect against muscle damage induced by
maximal eccentric exercise performed 2 days later.
Abstract: Most of the oil palm plantations have been threatened
by Basal Stem Rot (BSR) disease which causes serious economic
impact. This study was conducted to identify the healthy and BSRinfected
oil palm tree using thirteen color indices. Multispectral and
thermal camera was used to capture 216 images of the leaves taken
from frond number 1, 9 and 17. Indices of normalized difference
vegetation index (NDVI), red (R), green (G), blue (B), near infrared
(NIR), green – blue (GB), green/blue (G/B), green – red (GR),
green/red (G/R), hue (H), saturation (S), intensity (I) and thermal
index (T) were used. From this study, it can be concluded that G
index taken from frond number 9 is the best index to differentiate
between the healthy and BSR-infected oil palm trees. It not only gave
high value of correlation coefficient (R=-0.962), but also high value
of separation between healthy and BSR-infected oil palm tree.
Furthermore, power and S model developed using G index gave the
highest R2 value which is 0.985.
Abstract: Cyberspace has become a more viable arena for
budding artists to share musical acts through digital forms. The
increasing relevance of online communities has attracted scholars
from various fields demonstrating its influence on social capital. This
paper extends this understanding of social capital among Filipino
music artists belonging to the SoundCloud Philippines Facebook
Group.
The study makes use of various qualitative data obtained from
key-informant interviews and participant observation of online and
physical encounters, analyzed using the case study approach.
Soundcloud Philippines has over seven-hundred members and is
composed of Filipino singers, instrumentalists, composers, arrangers,
producers, multimedia artists and event managers. Group interactions
are a mix of online encounters based on Facebook and SoundCloud
and physical encounters through meet-ups and events. Benefits
reaped from the community are informational, technical,
instrumental, promotional, motivational and social support. Under the
guidance of online group administrators, collaborative activities such
as music productions, concerts and events transpire. Most conflicts
and problems arising are resolved peacefully. Social capital in
SoundCloud Philippines is mobilized through recognition, respect
and reciprocity.
Abstract: This paper presents Carrier Sense Multiple Access
(CSMA) communication models based on SoC design methodology.
Such a model can be used to support the modeling of the complex
wireless communication systems. Therefore, the use of such
communication model is an important technique in the construction
of high-performance communication. SystemC has been chosen
because it provides a homogeneous design flow for complex designs
(i.e. SoC and IP-based design). We use a swarm system to validate
CSMA designed model and to show how advantages of incorporating
communication early in the design process. The wireless
communication created through the modeling of CSMA protocol that
can be used to achieve communication between all the agents and to
coordinate access to the shared medium (channel).
Abstract: The Chair of Thermal Engineering at Poznan
University of Technology has been conducted research works on the
possibilities of using carbon nanostructures in energy and mechanics
applications for a couple of years. Those studies have provided results in a form of co-operation with foreign research centres, numerous publications and patent
applications.
Authors of this paper have studied the influence of multi-walled
carbon nanostructures on changes in static friction arising when steel
surfaces were moved. Tests were made using the original test stand
consisting of automatically controlled inclined plane driven by
precise stepper motors. Computer program created in the LabView
environment was responsible for monitoring of the stand operation,
accuracy of measurements and archiving the obtained results. Such a
solution enabled to obtain high accuracy and repeatability of all
conducted experiments.
Tests and analysis of the obtained results allowed us to determine
how additional layers of carbon nanostructures influenced on changes
of static friction coefficients. At the same time, we analyzed the
potential possibilities of applying nanostructures under consideration
in mechanics.
Abstract: Remote arid areas of the vast expanses of the African
deserts hold huge subterranean reserves of brackish water resources
waiting for economic development. This work presents design
guidelines as well as initial performance data of new autonomous
solar desalination equipment which could help local communities
produce their own fresh water using solar energy only and, why not,
contribute to transforming desert lands into lush gardens. The output
of solar distillation equipments are typically low and in the range of 3
l/m2/day on the average. This new design with an integrated, water
based, environmentally-friendly solar heat storage system produced 5
l/m2/day in early spring weather. Equipment output during summer
exceeded 9 liters per m2 per day.
Abstract: This paper presents the ‘Eye Ball Motion Controlled
Wheelchair using IR Sensors’ for the elderly and differently abled
people. In this eye tracking based technology, three Proximity
Infrared (IR) sensor modules are mounted on an eye frame to trace
the movement of the iris. Since, IR sensors detect only white objects;
a unique sequence of digital bits is generated corresponding to each
eye movement. These signals are then processed via a micro
controller IC (PIC18F452) to control the motors of the wheelchair.
The potential and efficiency of previously developed rehabilitation
systems that use head motion, chin control, sip-n-puff control, voice
recognition, and EEG signals variedly have also been explored in
detail. They were found to be inconvenient as they served either
limited usability or non-affordability. After multiple regression
analyses, the proposed design was developed as a cost-effective,
flexible and stream-lined alternative for people who have trouble
adopting conventional assistive technologies.
Abstract: The aim of this research was to reveal the link
between mental variables, such as spatial abilities, memory, intellect
and professional experience of drivers.
Participants were allocated to four groups: no experience,
inexperienced, skilled and professionals (total 85 participants). The
level of ability for spatial navigation and indicator of nonverbal
memory grow along the process of accumulation of driving
experience. At high levels of driving experience, this tendency is
especially noticeable. The professionals having personal
achievements in driving (racing) differ from skilled drivers in better
feeling of direction, which is specific for them not just in a short-term
situation of an experimental task, but also in life-size perspective.
The level of ability of mental rotation does not grow with the growth
of driving experience, which confirms the multiple intelligence
theory according to which spatial abilities represent specific, other
than logical intelligence type of intellect. The link between spatial
abilities, memory, intellect and professional experience of drivers
seems to be different relating spatial navigation or mental rotation as
different kinds of spatial abilities.
Abstract: In recent years, multi-antenna techniques are being considered as a potential solution to increase the flow of future wireless communication systems. The objective of this article is to study the emission and reception system MIMO (Multiple Input Multiple Output), and present the different reception decoding techniques. First we will present the least complex technical, linear receivers such as the zero forcing equalizer (ZF) and minimum mean squared error (MMSE). Then a nonlinear technique called ordered successive cancellation of interferences (OSIC) and the optimal detector based on the maximum likelihood criterion (ML), finally, we simulate the associated decoding algorithms for MIMO system such as ZF, MMSE, OSIC and ML, thus a comparison of performance of these algorithms in MIMO context.
Abstract: Implementation of advanced technologies requires
sophisticated instruments that deal with the operation, control,
restoration and protection of rapidly growing power system network
under normal and abnormal conditions. Presently, the applications of
Phasor Measurement Unit (PMU) are widely found in real time
operation, monitoring, controlling and analysis of power system
network as it eliminates the various limitations of supervisory control
and data acquisition system (SCADA) conventionally used in power
system. The use of PMU data is very rapidly increasing its
importance for online and offline analysis. Wide area measurement
system (WAMS) is developed as new technology by use of multiple
PMUs in power system. The present paper proposes a model of
Matlab based PMU using Discrete Fourier Transform (DFT)
algorithm and evaluation of its operation under different
contingencies. In this paper, PMU based two bus system having
WAMS network is presented as a case study.
Abstract: A novel method is presented for obtaining the stress
field induced by an edge dislocation in a multilayered composite. To
demonstrate the applications of the obtained solution, we consider the
problem of an interfacial crack in a periodically layered bimaterial
medium. The crack is modelled as a continuous distribution of edge
dislocations and the Distributed Dislocation Technique (DDT) is
utilized to obtain numerical results for the energy release rate (ERR).
The numerical implementation of the dislocation solution in
MATLAB is also provided.
Abstract: Due to today’s globalization as well as outsourcing
practices of the companies, the Supply Chain (SC) performances
have become more dependent on the efficient movement of material
among places that are geographically dispersed, where there is more
chance for disruptions. One such disruption is the quality and
delivery uncertainties of outsourcing. These uncertainties could lead
the products to be unsafe and, as is the case in a number of recent
examples, companies may have to end up in recalling their products.
As a result of these problems, there is a need to develop a
methodology for selecting suppliers globally in view of risks
associated with low quality and late delivery. Accordingly, we
developed a two-stage stochastic model that captures the risks
associated with uncertainty in quality and delivery as well as a
solution procedure for the model. The stochastic model developed
simultaneously optimizes supplier selection and purchase quantities
under price discounts over a time horizon. In particular, our target is
the study of global organizations with multiple sites and multiple
overseas suppliers, where the pricing is offered in suppliers’ local
currencies. Our proposed methodology is applied to a case study for a
US automotive company having two assembly plants and four
potential global suppliers to illustrate how the proposed model works
in practice.
Abstract: In this paper a new methodology for vendor selection
and supply quotas determination (VSSQD) is proposed. The problem
of VSSQD is solved by the model that combines revised weighting
method for determining the objective function coefficients, and a
multiple objective linear programming (MOLP) method based on the
cooperative game theory for VSSQD. The criteria used for VSSQD
are: (1) purchase costs and (2) product quality supplied by individual
vendors. The proposed methodology has been tested on the example
of flour purchase for a bakery with two decision makers.
Abstract: This paper describes the main features of a knowledge-based system evaluation method. System evaluation is placed in the context of a hybrid legal decision-support system, Advisory Support for Home Settlement in Divorce (ASHSD). Legal knowledge for ASHSD is represented in two forms, as rules and previously decided cases. Besides distinguishing the two different forms of knowledge representation, the paper outlines the actual use of these forms in a computational framework that is designed to generate a plausible solution for a given case, by using rule-based reasoning (RBR) and case-based reasoning (CBR) in an integrated environment. The nature of suitability assessment of a solution has been considered as a multiple criteria decision-making process in ASHAD evaluation. The evaluation was performed by a combination of discussions and questionnaires with different user groups. The answers to questionnaires used in this evaluations method have been measured as a fuzzy linguistic term. The finding suggests that fuzzy linguistic evaluation is practical and meaningful in knowledge-based system development purpose.
Abstract: This paper presents an application of a “Systematic
Soft Domain Driven Design Framework” as a soft systems approach
to domain-driven design of information systems development. The
framework use SSM as a guiding methodology within which we have
embedded a sequence of design tasks based on the UML leading to
the implementation of a software system using the Naked Objects
framework. This framework have been used in action research
projects that have involved the investigation and modelling of
business processes using object-oriented domain models and the
implementation of software systems based on those domain models.
Within this framework, Soft Systems Methodology (SSM) is used as
a guiding methodology to explore the problem situation and to
develop the domain model using UML for the given business
domain. The framework is proposed and evaluated in our previous
works, and a real case study “Information Retrieval System for
academic research” is used, in this paper, to show further practice and
evaluation of the framework in different business domain. We argue
that there are advantages from combining and using techniques from
different methodologies in this way for business domain modelling.
The framework is overviewed and justified as multimethodology
using Mingers multimethodology ideas.