Abstract: High pressure turbine (HPT) blades of DV – 2 jet
engines are made from Ni – based superalloy. This alloy was
originally manufactured in the Soviet Union and referred as ŽS6K.
For improving alloy’s high temperature resistance are blades coated
with Al – Si diffusion layer. A regular operation temperature of HPT
blades vary from 705°C to 750°C depending on jet engine regime.
An overcrossing working temperature range causes degradation of
the protective coating as well as base material which microstructure
is formed by the gamma matrix and strengthening phase gamma
prime (forming small particles in the microstructure). Diffusion
processes inside the material during exposition of the material to high
temperatures causes mainly coarsening of the gamma prime particles,
thus decreasing its strengthening effect. Degradation of the Al – Si
coating caused its thickness growth. All the microstructure changes
and coating layer thickness growth results in decreasing of the turbine
blade operation lifetime.
Abstract: The authors propose the identification, analysis and
prognosis of the quantitative and qualitative evolution of the elderly
population in the functional urban areas. The present paper takes into
account the analysis of some representative indicators (the weight of
the elderly population, ageing index, dynamic index of economic
ageing of productive population etc.) and the elaboration of an
integrated indicator that would help differentiate the population
ageing forms in the 48 functional urban areas that were defined based
on demographic and social-economic criteria for all large and
medium cities in Romania.
Abstract: A central element of higher education today is the
“core” or “general education” curriculum: that configuration of
courses that often encompasses the essence of liberal arts education.
Ensuring that such offerings reflect the mission and values of the
institution is a challenge faced by most college and universities, often
more than once. This paper presents an action model of program
planning designed to structure the processes of developing,
implementing and revising core curricula in a manner consistent with
key institutional goals and objectives. Through presentation of a case
study from a university in the United States, the elements of needs
assessment, stakeholder investment and collaborative compromise
are shown as key components of a planning strategy that can produce
a general education program that is comprehensive, academically
rigorous, assessable, and mission consistent. The paper concludes
with recommendations for both the implementation and evaluation of
such programs in practice.
Abstract: This paper is part of a study to develop robots for
farming. As such power requirement to operate equipment attach to
such robots become an important factor. Soil-tool interaction plays
major role in power consumption, thus predicting accurately the
forces which act on the blade during the farming is very important for
optimal designing of farm equipment. In this paper, a finite element
investigation for tillage tools and soil interaction is described by
using an inelastic constitutive material law for agriculture
application. A 3-dimensional (3D) nonlinear finite element analysis
(FEA) is developed to examine behavior of a blade with different
rake angles moving in a block of soil, and to estimate the blade force.
The soil model considered is an elastic-plastic with non-associated
Drucker-Prager material model. Special use of contact elements are
employed to consider connection between soil-blade and soil-soil
surfaces. The FEA results are compared with experimental ones,
which show good agreement in accurately predicting draft forces
developed on the blade when it moves through the soil. Also a very
good correlation was obtained between FEA results and analytical
results from classical soil mechanics theories for straight blades.
These comparisons verified the FEA model developed. For analyzing
complicated soil-tool interactions and for optimum design of blades,
this method will be useful.
Abstract: Indonesian higher education has experienced
significant changes over the last decade. In 1999, the government
published an overall strategy for decentralisation and enhancement of
local autonomy in many sectors, including (higher) education.
Indonesian higher education reforms have forced universities to
restructure their internal university governance to become more
entrepreneurial. These new types of internal university governance
are likely to affect the institutions’ leadership and management. This
paper discusses the approach and findings of a study on the
managerial leadership styles of deans in Indonesian universities. The
study aims to get a better understanding of styles exhibited by deans
manifested in their behaviours. Using the theories of reasoned action
and planned behaviour, in combination with the competing values
framework, a large-scale survey was conducted to gather information
on the deans’ behaviours, attitudes, subjective norms, and perceived
behavioural control. Based on the responses of a sample of 218
deans, the study identifies a number of leadership styles: the Master,
the Competitive Consultant, the Consensual Goal-Setter, the Focused
Team Captain, and the Informed Trust-Builder style. The study
demonstrates that attitudes are the primary determinant of the styles
that were found. Perceived behavioural control is a factor that
explains some managerial leadership styles. By understanding the
attitudes of deans in Indonesian universities, and their leadership
styles, universities can strengthen their management and governance,
and thus improve their effectiveness.
Abstract: In the past few years, the amount of malicious software
increased exponentially and, therefore, machine learning algorithms
became instrumental in identifying clean and malware files through
(semi)-automated classification. When working with very large
datasets, the major challenge is to reach both a very high malware
detection rate and a very low false positive rate. Another challenge
is to minimize the time needed for the machine learning algorithm to
do so. This paper presents a comparative study between different
machine learning techniques such as linear classifiers, ensembles,
decision trees or various hybrids thereof. The training dataset consists
of approximately 2 million clean files and 200.000 infected files,
which is a realistic quantitative mixture. The paper investigates the
above mentioned methods with respect to both their performance
(detection rate and false positive rate) and their practicability.
Abstract: Every year, a considerable amount of money is being
invested on research, mainly in the form of funding allocated to
universities and research institutes. To better distribute the available
funds and to set the most proper R&D investment strategies for the
future, evaluation of the productivity of the funded researchers and
the impact of such funding is crucial. In this paper, using the data on
15 years of journal publications of the NSERC (Natural Sciences and
Engineering research Council of Canada) funded researchers and by
means of bibliometric analysis, the scientific development of the
funded researchers and their scientific collaboration patterns will be
investigated in the period of 1996-2010. According to the results it
seems that there is a positive relation between the average level of
funding and quantity and quality of the scientific output. In addition,
whenever funding allocated to the researchers has increased, the
number of co-authors per paper has also augmented. Hence, the
increase in the level of funding may enable researchers to get
involved in larger projects and/or scientific teams and increase their
scientific output respectively.
Abstract: One of the crucial parameters of digital cryptographic
systems is the selection of the keys used and their distribution. The
randomness of the keys has a strong impact on the system’s security
strength being difficult to be predicted, guessed, reproduced, or
discovered by a cryptanalyst. Therefore, adequate key randomness
generation is still sought for the benefit of stronger cryptosystems.
This paper suggests an algorithm designed to generate and test
pseudo random number sequences intended for cryptographic
applications. This algorithm is based on mathematically manipulating
a publically agreed upon information between sender and receiver
over a public channel. This information is used as a seed for
performing some mathematical functions in order to generate a
sequence of pseudorandom numbers that will be used for
encryption/decryption purposes. This manipulation involves
permutations and substitutions that fulfill Shannon’s principle of
“confusion and diffusion”. ASCII code characters were utilized in the
generation process instead of using bit strings initially, which adds
more flexibility in testing different seed values. Finally, the obtained
results would indicate sound difficulty of guessing keys by attackers.
Abstract: This paper proposes the application of the Smart
Security Concept in the East Mediterranean. Smart Security aims to
secure critical infrastructure, such as hydrocarbon platforms, against
asymmetrical threats. The concept is based on Anti Asymmetrical
Area Denial (A3D) which necessitates limiting freedom of action of
maritime terrorists and piracy by founding safe and secure maritime
areas through sea lines of communication using short range
capabilities.
Abstract: The objective of present research paper is to highlight
the importance of measuring advertisement effectiveness in print
media and to develop a conceptual model for advertisement
effectiveness. The developed model is based on dimensions on which
advertisement effectiveness depends and on the dimensions which are
used to measure the effectiveness. An in-depth and extensive
literature review is carried out to understand the concept of
advertisement effectiveness and its various determinants in context of
print media. Based on the insights gained, a conceptual framework
for advertisement effectiveness is presented. The model is an attempt
to uncover the relatively less explored area of advertisement
effectiveness in Indian advertising scenario. It is believed that present
work will encourage scholars and academicians to further explore the
area and will offer conceptual assistance and a fresh direction in the
domain of advertisement effectiveness.
Abstract: DC motors have been widely used in the past
centuries which are proudly known as the workhorse of industrial
systems until the invention of the AC induction motors which makes
a huge revolution in industries. Since then, the use of DC machines
has been decreased due to enormous factors such as reliability,
robustness and complexity but it lost its fame due to the losses. In this
paper a new methodology is proposed to construct a DC motor
through the simulation in LabVIEW to get an idea about its real time
performances, if a change in parameter might have bigger
improvement in losses and reliability.
Abstract: Proposed paper dealt with the modelling and analysis of induction motor based on the mathematical expression using the graphical programming environment of Laboratory Virtual Instrument Engineering Workbench (LabVIEW). Induction motor modelling with the mathematical expression enables the motor to be simulated with the various required parameters. Owing to the invention of variable speed drives study about the induction motor characteristics became complex. In this simulation motor internal parameter such as stator resistance and reactance, rotor resistance and reactance, phase voltage, frequency and losses will be given as input. By varying the speed of motor corresponding parameters can be obtained they are input power, output power, efficiency, torque induced, slip and current.
Abstract: A total of 115 yeast strains isolated from local cassava
processing wastes were measured for crude protein content. Among
these strains, the strain MSY-2 possessed the highest protein
concentration (>3.5 mg protein/mL). By using molecular
identification tools, it was identified to be a strain of Pichia
kudriavzevii based on similarity of D1/D2 domain of 26S rDNA
region. In this study, to optimize the protein production by MSY-2
strain, Response Surface Methodology (RSM) was applied. The
tested parameters were the carbon content, nitrogen content, and
incubation time. Here, the value of regression coefficient (R2) =
0.7194 could be explained by the model which is high to support the
significance of the model. Under the optimal condition, the protein
content was produced up to 3.77 g per L of the culture and MSY-2
strain contains 66.8 g protein per 100 g of cell dry weight. These
results revealed the plausibility of applying the novel strain of yeast
in single-cell protein production.
Abstract: Non contact evaluation of the thickness of paint
coatings can be attempted by different destructive and nondestructive
methods such as cross-section microscopy, gravimetric mass
measurement, magnetic gauges, Eddy current, ultrasound or
terahertz. Infrared thermography is a nondestructive and non-invasive
method that can be envisaged as a useful tool to measure the surface
thickness variations by analyzing the temperature response. In this
paper, the thermal quadrupole method for two layered samples heated
up with a pulsed excitation is firstly used. By analyzing the thermal
responses as a function of thermal properties and thicknesses of both
layers, optimal parameters for the excitation source can be identified.
Simulations show that a pulsed excitation with duration of ten
milliseconds allows obtaining a substrate-independent thermal
response. Based on this result, an experimental setup consisting of a
near-infrared laser diode and an Infrared camera was next used to
evaluate the variation of paint coating thickness between 60 μm and
130 μm on two samples. Results show that the parameters extracted
for thermal images are correlated with the estimated thicknesses by
the Eddy current methods. The laser pulsed thermography is thus an
interesting alternative nondestructive method that can be moreover
used for nonconductive substrates.
Abstract: Turkish migrants constitute the largest group among
people with migration background living in Germany. Turkish
women’s labor market participation is of significant importance for
their social and economic integration to the German society. This
paper thus aims to investigate their labor market positions. Turkish
migrant women participate less in the labor market compared to men,
and are responsible for most of the housework, child care, and elderly
care. This is due to their traditional roles in the family, educational
level, insufficient knowledge of German language, and insufficient
professional experience. We strongly recommend that wide-reaching
integration policies for women are formulated, so as to encourage
participation of not only migrant women but also their husbands,
fathers and/or brothers, and natives.
Abstract: Rainfall runoff models play important role in
hydrological predictions. However, the model is only one part of the
process for creation of flood prediction. The aim of this paper is to
show the process of successful prediction for flood event (May 15 –
May 18 2014). Prediction was performed by rainfall runoff model
HEC–HMS, one of the models computed within Floreon+ system.
The paper briefly evaluates the results of automatic hydrologic
prediction on the river Olše catchment and its gages Český Těšín and
Věřňovice.
Abstract: The first part of the paper analyzes the dynamics of
the total fertility rate both at the national and regional level, pointing
out the regional disparities in the distribution of this indicator. At the
same time, we also focus on the collapse of the number of live births,
on the changes in the fertility rate by birth rank, as well as on the
failure of acquiring the desired number of children. The second part
of the study centres upon a survey applied to urban families with 3
and more than 3 offspring. The preliminary analysis highlights the
fact that an increased fertility (more than 3rd rank) is triggered by the
parents’ above the average material condition and superior education.
The current situation of Romania, which is still passing through a
period of relatively rapid demographic changes, marked by numerous
convulsions, requires a new approach, in compliance with the recent
interpretations appropriate to a new post-transitional demographic
regime.
Abstract: The paper presents a method for a simple and
immediate motion planning of a SCARA robot, whose end-effector
has to move along a given trajectory; the calculation procedure
requires the user to define in analytical form or by points the
trajectory to be followed and to assign the curvilinear abscissa as
function of the time. On the basis of the geometrical characteristics
of the robot, a specifically developed program determines the motion
laws of the actuators that enable the robot to generate the required
movement; this software can be used in all industrial applications for
which a SCARA robot has to be frequently reprogrammed, in order
to generate various types of trajectories with different motion times.
Abstract: We proposed a Hyperbolic Gompertz Growth Model
(HGGM), which was developed by introducing a shape parameter
(allometric). This was achieved by convoluting hyperbolic sine
function on the intrinsic rate of growth in the classical gompertz
growth equation. The resulting integral solution obtained
deterministically was reprogrammed into a statistical model and used
in modeling the height and diameter of Pines (Pinus caribaea). Its
ability in model prediction was compared with the classical gompertz
growth model, an approach which mimicked the natural variability of
height/diameter increment with respect to age and therefore provides
a more realistic height/diameter predictions using goodness of fit
tests and model selection criteria. The Kolmogorov Smirnov test and
Shapiro-Wilk test was also used to test the compliance of the error
term to normality assumptions while the independence of the error
term was confirmed using the runs test. The mean function of top
height/Dbh over age using the two models under study predicted
closely the observed values of top height/Dbh in the hyperbolic
gompertz growth models better than the source model (classical
gompertz growth model) while the results of R2, Adj. R2, MSE and
AIC confirmed the predictive power of the Hyperbolic Gompertz
growth models over its source model.
Abstract: Transmission shafts are affected by various forces, for
example, during acceleration or sudden breaks, bending during
transportation, vertical forces that lead to cuts. One of the main
failures in combines is breaking shaft which repairmen refer it.
Structural resistance of canal against torque is very important in the
beginning of the movement. For analyzing stress, a typical sample
from a type of combine was selected, called JD955 combine. Long
shaft in this combine was analyzed with finite element method by
Ansys13 generic package under static load. Conducted analysis
showed that there is a maximum stress in contact surfaces of
indentations and also in place of changing diameter. Safety factor
value is low in parts of the shaft and this increases the probability of
failure at these points. To improve the conditions with the least cost
and an approach of product improvement, using alternative alloy is
important.