Abstract: In this work a surgical simulator is produced which
enables a training otologist to conduct a virtual, real-time prosthetic
insertion. The simulator provides the Ear, Nose and Throat surgeon
with real-time visual and haptic responses during virtual cochlear
implantation into a 3D model of the human Scala Tympani (ST). The
parametric model is derived from measured data as published in the
literature and accounts for human morphological variance, such as
differences in cochlear shape, enabling patient-specific pre- operative
assessment. Haptic modeling techniques use real physical data and
insertion force measurements, to develop a force model which
mimics the physical behavior of an implant as it collides with the ST
walls during an insertion. Output force profiles are acquired from the
insertion studies conducted in the work, to validate the haptic model.
The simulator provides the user with real-time, quantitative insertion
force information and associated electrode position as user inserts the
virtual implant into the ST model. The information provided by this
study may also be of use to implant manufacturers for design
enhancements as well as for training specialists in optimal force
administration, using the simulator. The paper reports on the methods
for anatomical modeling and haptic algorithm development, with
focus on simulator design, development, optimization and validation.
The techniques may be transferrable to other medical applications
that involve prosthetic device insertions where user vision is
obstructed.
Abstract: The fundamental defect inherent to the thermoforming
technology is wall-thickness variation of the products due to
inadequate thermal processing during production of polymer. A
nonlinear viscoelastic rheological model is implemented for
developing the process model. This model describes deformation
process of a sheet in thermoforming process. Because of relaxation
pause after plug-assist stage and also implementation of two stage
thermoforming process have minor wall-thickness variation and
consequently better mechanical properties of polymeric articles. For
model validation, a comparative analysis of the theoretical and
experimental data is presented.
Abstract: This paper presents a unified approach based graph
theory and system theory postulates for the modeling and analysis
of Simple open cycle Gas turbine system. In the present paper, the
simple open cycle gas turbine system has been modeled up to its subsystem
level and system variables have been identified to develop the
process subgraphs. The theorems and algorithms of the graph theory
have been used to represent behavioural properties of the system like
rate of heat and work transfers rates, pressure drops and temperature
drops in the involved processes of the system. The processes have
been represented as edges of the process subgraphs and their limits
as the vertices of the process subgraphs. The system across variables
and through variables has been used to develop terminal equations of
the process subgraphs of the system. The set of equations developed
for vertices and edges of network graph are used to solve the system
for its process variables.
Abstract: This paper is mainly concerned with the application of a novel technique of data interpretation to the characterization and classification of measurements of plasma columns in Tokamak reactors for nuclear fusion applications. The proposed method exploits several concepts derived from soft computing theory. In particular, Artifical Neural Networks have been exploited to classify magnetic variables useful to determine shape and position of the plasma with a reduced computational complexity. The proposed technique is used to analyze simulated databases of plasma equilibria based on ITER geometry configuration. As well as demonstrating the successful recovery of scalar equilibrium parameters, we show that the technique can yield practical advantages compares with earlier methods.
Abstract: Modern organizations operate under the pressure of
dynamic and often unpredictable changes, both in external and
internal environment. Market success, in this context, requires a
particular competence in the form of flexibility, interpreted here both
on the level of individuals and on the level of organization. This
paper addresses the changes taking place in the sphere of
employment, as observed in economic entities operating on Polish
market. Based on own empirical studies, the authors focus on the
progressing trend of ‘flexibilization’ of employment, particularly in
the context of transformations in organizational structure, designed to
facilitate the transition into management by projects and
differentiation of labor forms.
Abstract: A finite element analysis (FEA) computer software HyperWorks is utilized in re-designing an automotive component to reduce its mass. Reduction of components mass contributes towards environmental sustainability by saving world-s valuable metal resources and by reducing carbon emission through improved overall vehicle fuel efficiency. A shape optimization analysis was performed on a rear spindle component. Pre-processing and solving procedures were performed using HyperMesh and RADIOSS respectively. Shape variables were defined using HyperMorph. Then optimization solver OptiStruct was utilized with fatigue life set as a design constraint. Since Stress-Number of Cycle (S-N) theory deals with uni-axial stress, the Signed von Misses stress on the component was used for looking up damage on S-N curve, and Gerber criterion for mean stress corrections. The optimization analysis resulted in mass reduction of 24% of the original mass. The study proved that the adopted approach has high potential use for environmental sustainability.
Abstract: Integration of system process information obtained
through an image processing system with an evolving knowledge
database to improve the accuracy and predictability of wear particle
analysis is the main focus of the paper. The objective is to automate
intelligently the analysis process of wear particle using classification
via self organizing maps. This is achieved using relationship
measurements among corresponding attributes of various
measurements for wear particle. Finally, visualization technique is
proposed that helps the viewer in understanding and utilizing these
relationships that enable accurate diagnostics.
Abstract: For the last decade, statistics show traumatic brain
injury (TBI) is a growing concern in our legal system. In an effort to
obtain data regarding the influence of neuropsychological expert
witness testimony in a criminal case, this study tested three
hypotheses. H1: The majority of jurors will vote not guilty, due to
mild head injury. H2: The jurors will give more credence to the
testimony of the neuropsychologist rather than the psychiatrist. H3:
The jurors will be more lenient in their sentencing, given the
testimony of the neuropsychologist-s testimony. The criterion for
inclusion in the study as a participant is identical to those used for
inclusion in the eligibility for jury duty in the United States. A chisquared
test was performed to analyze the data for the three
hypotheses. The results supported all of the hypotheses; however
statistical significance was seen in H1 and H2 only.
Abstract: Despite the fact that B2c eCommerce has become
important in numerous economies, its adoption varies from country to
country. This paper aims to identify the factors affecting (enabling or
inhibiting) B2c eCommerce and to determine their quantitative
impact on the diffusion of online sales across countries. A dynamic
panel model analyzing the relationship between 13 factors
(Macroeconomic, Demographic, Socio-Cultural, Infrastructural and
Offer related) stemming from a complete literature analysis and the
B2c eCommerce value in 45 countries over 9 years has been
developed. Having a positive correlation coefficient, GDP, mobile
penetration, Internet user penetration and credit card penetration
resulted as enabling drivers of the B2c eCommerce value across
countries, whereas, having a negative correlation coefficient,equal
distribution of income and the development of traditional retailing
network act as inhibiting factors.
Abstract: The conceptually construction of axially chiral indolostilbenesi.eN-(2-{(E)-2-[2'-(1-Acetyl-1H-indol-2-yl)-3'chloro-4,4',6,6'-tetramethoxy[1,1'-biphenyl]-2yl]ethenyl}phenyl)acetamide and N-(2-{(E)-2-[2'-(1-Acetyl-1H-indol-2-yl)-3'-chloro-2,4',6,6'-tetramethoxy[1,1'-biphenyl]-4-yl]ethenyl}phenyl) acetamide are described in this paper. These structure, were obtained by the tactical combination of palladium-catalyzed coupling which produced 10-acetamido-3,5-dimethoxystilbene, follow by FeCl3-induced oxidative cyclization/dimerisation. All structures were unambiguously confirmed by 1D (1H, 13C) and 2D NMR experiment, (COSY, HMQC, HMBC) and mass spectrometry.
Abstract: The development of competences and practical
capacities of students is getting an important incidence into the
guidelines of the European Higher Education Area (EHEA). The
methodology applied in this work is based on the education through
directed resolution of practical cases. All cases are related to
professional tasks that the students will have to develop in their
future career. The method is intended to form the necessary
competences of students of the Marine Engineering and Maritime
Transport Degree in the matter of “Physics".
The experience was applied in the course of 2011/2012. Students
were grouped, and a practical task was assigned to them, that should
be developed and solved within the team. The aim was to realize
students learning by three ways: their own knowledge, the
contribution of their teammates and the teacher's direction. The
results of the evaluation were compared with those obtained
previously by the traditional teaching method.
Abstract: Although lots of experiments have been done in enhanced oil recovery, the number of experiments which consider the effects of local and global heterogeneity on efficiency of enhanced oil recovery based on the polymer-surfactant flooding is low and rarely done. In this research, we have done numerous experiments of water flooding and polymer-surfactant flooding on a five spot glass micromodel in different conditions such as different positions of layers. In these experiments, five different micromodels with three different pore structures are designed. Three models with different layer orientation, one homogenous model and one heterogeneous model are designed. In order to import the effect of heterogeneity of porous media, three types of pore structures are distributed accidentally and with equal ratio throughout heterogeneous micromodel network according to random normal distribution. The results show that maximum EOR recovery factor will happen in a situation where the layers are orthogonal to the path of mainstream and the minimum EOR recovery factor will happen in a situation where the model is heterogeneous. This experiments show that in polymer-surfactant flooding, with increase of angles of layers the EOR recovery factor will increase and this recovery factor is strongly affected by local heterogeneity around the injection zone.
Abstract: In the last few years, three multivariate spectral
analysis techniques namely, Principal Component Analysis (PCA),
Independent Component Analysis (ICA) and Non-negative Matrix
Factorization (NMF) have emerged as effective tools for oscillation
detection and isolation. While the first method is used in determining
the number of oscillatory sources, the latter two methods
are used to identify source signatures by formulating the detection
problem as a source identification problem in the spectral domain.
In this paper, we present a critical drawback of the underlying linear
(mixing) model which strongly limits the ability of the associated
source separation methods to determine the number of sources
and/or identify the physical source signatures. It is shown that the
assumed mixing model is only valid if each unit of the process gives
equal weighting (all-pass filter) to all oscillatory components in its
inputs. This is in contrast to the fact that each unit, in general, acts
as a filter with non-uniform frequency response. Thus, the model
can only facilitate correct identification of a source with a single
frequency component, which is again unrealistic. To overcome
this deficiency, an iterative post-processing algorithm that correctly
identifies the physical source(s) is developed. An additional issue
with the existing methods is that they lack a procedure to pre-screen
non-oscillatory/noisy measurements which obscure the identification
of oscillatory sources. In this regard, a pre-screening procedure
is prescribed based on the notion of sparseness index to eliminate
the noisy and non-oscillatory measurements from the data set used
for analysis.
Abstract: Knowledge of patterns of genetic diversity enhances
the efficiency of germplasm conservation and improvement. In this
study 96 Iranian landraces of Triticum turgidum originating from
different geographical areas of Iran, along with 18 durum cultivars
from ten countries were evaluated for variation in morphological and
high molecular weight glutenin subunit (HMW-GS) composition.
The first two principal components clearly separated the Iranian
landraces from cultivars. Three alleles were present at the Glu-A1
locus and 11 alleles at Glu-B1. In both cultivars and landraces of
durum wheat, the null allele (Glu-A1c) was observed more
frequently than the Glu-A1a and Glu-A1b alleles. Two alleles,
namely Glu-B1a (subunit 7) and Glu-B1e (subunit 20) represented
the more frequent alleles at Glu-B1 locus. The results showed that
the evaluated Iranian landraces formed an interesting source of
favourable glutenin subunits that might be very desirable in breeding
activities for improving pasta-making quality.
Abstract: Capacity and efficiency of any refrigerating system
diminish rapidly as the difference between the evaporating and
condensing temperature is increased by a reduction in the evaporator
temperature. The single stage vapour compression refrigeration
system using various refrigerants are limited to an evaporator
temperature of -40 0C. Below temperature of -40 0C the either
cascade refrigeration system or multi stage vapour compression
system is employed. Present work describes thermal design of
condenser (HTS), cascade condenser and evaporator (LTS) of
R404A-R508B and R410A-R23 cascade refrigeration system. Heat
transfer area of condenser, cascade condenser and evaporator for
both systems are compared and the effect of condenser and
evaporator temperature on heat-transfer area for both systems is
studied under same operating condition. The results shows that the
required heat-transfer area of condenser and cascade condenser for
R410A-R23 cascade system is lower than the R404A-R508B cascade
system but heat transfer area of evaporator is similar for both the
system. The heat transfer area of condenser and cascade condenser
decreases with increase in condenser temperature (Tc), whereas the
heat transfer area of cascade condenser and evaporator increases with
increase in evaporator temperature (Te).
Abstract: The increasing influence of traffic on building
objects and people residing in them should be taken into account in
diagnosis and design. Users of buildings expect that vibrations
occurring in their environment, will not only lead to damage to the
building or its accelerated wear, but neither would affect the required
comfort in rooms designed to accommodate people. This article
describes the methods and principles useful in designing and building
diagnostics located near transportation routes, with particular
emphasis on the impact of traffic vibration on people in buildings. It
also describes the procedures used in obtaining information about the
parameters of vibrations in different cases of diagnostics and design.
A universal algorithm of procedure in diagnostics and design of
buildings taking into account assurance of human vibration comfort
of people residing in the these buildings was presented.
Abstract: In this study, optimization is carried out to find the optimized design of a foam-filled column for the best Specific Energy Absorption (SEA) and Crush Force Efficiency (CFE). In order to maximize SEA, the optimization gives the value of 2.3 for column thickness and 151.7 for foam length. On the other hand to maximize CFE, the optimization gives the value of 1.1 for column thickness and 200 for foam length. Finite Element simulation is run by using this value and the SEA and CFE obtained 1237.76 J/kg and 0.92.
Abstract: In the past decade, because of wide applications of
hybrid systems, many researchers have considered modeling and
control of these systems. Since switching systems constitute an
important class of hybrid systems, in this paper a method for optimal
control of linear switching systems is described. The method is also
applied on the two-tank system which is a much appropriate system
to analyze different modeling and control techniques of hybrid
systems. Simulation results show that, in this method, the goals of
control and also problem constraints can be satisfied by an
appropriate selection of cost function.
Abstract: The complexity of teaching English in higher
institutions by non-native speakers within a second/foreign language
setting has created continuous discussions and research about
teaching approaches and teaching practises, professional identities
and challenges. In addition, there is a growing awareness that
teaching English within discipline-specific contexts adds up to the
existing complexity. This awareness leads to reassessments,
discussions and suggestions on course design and content and
teaching approaches and techniques. In meeting expectations
teaching at a university specified in a particular discipline such as
engineering, English language educators are not only required to
teach students to be able to communicate in English effectively but
also to teach soft skills such as problem solving skills. This paper is
part of a research conducted to investigate how English language
educators negotiate with the complexities of teaching problem
solving skills through English language teaching at a technical
university. This paper reports the way an English language educator
identified himself and the way he approached his teaching in this
institutional context.
Abstract: The morphological parameter of a thin film surface
can be characterized by power spectral density (PSD) functions
which provides a better description to the topography than the RMS
roughness and imparts several useful information of the surface
including fractal and superstructure contributions. Through the
present study Nanoparticle copper/carbon composite films were
prepared by co-deposition of RF-Sputtering and RF-PECVD method
from acetylene gas and copper target. Surface morphology of thin
films is characterized by using atomic force microscopy (AFM). The
Carbon content of our films was obtained by Rutherford Back
Scattering (RBS) and it varied from .4% to 78%. The power values of
power spectral density (PSD) for the AFM data were determined by
the fast Fourier transform (FFT) algorithms. We investigate the effect
of carbon on the roughness of thin films surface. Using such
information, roughness contributions of the surface have been
successfully extracted.