Abstract: The characterization and modeling of the dynamic
behavior of many built-up structures under vibration conditions is still
a subject of current research. The present study emphasizes the
theoretical investigation of slip damping in layered and jointed
welded cantilever structures using finite element approach.
Application of finite element method in damping analysis is relatively
recent, as such, some problems particularly slip damping analysis has
not received enough attention. To validate the finite element model
developed, experiments have been conducted on a number of mild
steel specimens under different initial conditions of vibration. Finite
element model developed affirms that the damping capacity of such
structures is influenced by a number of vital parameters such as;
pressure distribution, kinematic coefficient of friction and micro-slip
at the interfaces, amplitude, frequency of vibration, length and
thickness of the specimen. Finite element model developed can be
utilized effectively in the design of machine tools, automobiles,
aerodynamic and space structures, frames and machine members for
enhancing their damping capacity.
Abstract: Addition of an oily waste to a co-composting process of dairy cow manure with food waste, and the influence in the final product was evaluated. Three static composting piles with different substrates concentrations were assessed. Sawdust was also added to all composting piles to attain 60%, humidity at the beginning of the process. In pile 1, the co-substrates were the solid-phase of dairy cow manure, food waste and sawdust as bulking agent. In piles 2 and 3 there was an extra input of oily waste of 7 and 11% of the total volume, respectively, corresponding to 18 and 28% in dry weight. The results showed that the co-composting process was feasible even at the highest fat content. Another positive effect due to the oily waste addition was the requirement of extra humidity, due to the hydrophobic properties of this specific waste, which may imply reduced need of a bulking agent. Moreover, this study shows that composting can be a feasible way of adding value to fatty wastes. The three final composts presented very similar and suitable properties for land application.
Abstract: This qualitative, quantitative mixed-method study explores how students- motivation and interest in creative hands-on activities affected their conceptual understanding of science. The objectives of this research include developing a greater understanding about how creative activities, incorporated into the classroom as instructional strategies, increase student motivation and their learning or mastery of science concepts. The creative activities are viewed as a motivational tool, a specific type of task, which have an impact on student goals. Pre-and-post tests, pre-and-post interviews, and student responses measure motivational-goal theory variables, interest in the activity, and conceptual change. Implications for education and future research will be discussed.
Abstract: The international society focuses on the environment
protection and natural energy sources control for the global
cooperation against weather change and sustainable growth. The study
presents the overview of the water shortage status and the necessity of wastewater reuse facility in military facilities and for the possibility of
the introduction, compares the economics by means of cost-benefit
analysis. The military features such as the number of users of military barracks and the water use were surveyed by the design principles by
facility types, the application method of wastewater reuse facility was selected, the feed water, its application and the volume of reuse volume were defined and the expectation was estimated, confirming
the possibility of introducing a wastewater reuse possibility by means of cost-benefit analysis.
Abstract: HIV-1 genome is highly heterogeneous. Due to this
variation, features of HIV-I genome is in a wide range. For this
reason, the ability to infection of the virus changes depending on
different chemokine receptors. From this point of view, R5 HIV
viruses use CCR5 coreceptor while X4 viruses use CXCR5 and
R5X4 viruses can utilize both coreceptors. Recently, in
Bioinformatics, R5X4 viruses have been studied to classify by using
the experiments on HIV-1 genome.
In this study, R5X4 type of HIV viruses were classified using
Auto Regressive (AR) model through Artificial Neural Networks
(ANNs). The statistical data of R5X4, R5 and X4 viruses was
analyzed by using signal processing methods and ANNs. Accessible
residues of these virus sequences were obtained and modeled by AR
model since the dimension of residues is large and different from
each other. Finally the pre-processed data was used to evolve various
ANN structures for determining R5X4 viruses. Furthermore ROC
analysis was applied to ANNs to show their real performances. The
results indicate that R5X4 viruses successfully classified with high
sensitivity and specificity values training and testing ROC analysis
for RBF, which gives the best performance among ANN structures.
Abstract: The aim of this paper is to introduce the concepts of τ1τ2-regular generalized star star closed sets , τ1τ2-regular generalized star star open sets and study their basic properties in bitopological spaces.
Abstract: The prediction of meteorological parameters at a
meteorological station is an interesting and open problem. A firstorder
linear dynamic model GM(1,1) is the main component of the
grey system theory. The grey model requires only a few previous data
points in order to make a real-time forecast. In this paper, we
consider the daily average ambient temperature as a time series and
the grey model GM(1,1) applied to local prediction (short-term
prediction) of the temperature. In the same case study we use a fuzzy
predictive model for global prediction. We conclude the paper with a
comparison between local and global prediction schemes.
Abstract: Together with the industrialization, women began to
be included in business life by peeling off of the tasks given them by
society and they have become a factor of production creating value in
economic and social sense. Thus, women have taken place in the
labor market, majority of which has been formed by men. In this
study, the experiences of women entrepreneurs, who succeed in
business activities, will be analyzed. By the study, current state of the
women entrepreneurs in the labor market of Turkey will be put down,
as a result of interferences obtained from the shared experiences of
women entrepreneurs. Findings obtained at the end of the study are
thought to light the way of future studies for increasing women
entrepreneurship.
Abstract: Language Reforms and potential use of ICTs has been a focal area of Higher Education Commission of Pakistan. Efforts are being accelerated to incorporate fast expanding ICTs to bring qualitative improvement in language instruction in higher education. This paper explores how university teachers are benefitting from ICTs to make their English class effective and what type of problems they face in practicing ICTs during their lectures. An in-depth qualitative study was employed to understand why language teachers tend to use ICTs in their instruction and how they are practicing it. A sample of twenty teachers from five universities located in Islamabad, three from public sector and two from private sector, was selected on non-random (Snowball) sampling basis. An interview with 15 semi-structured items was used as research instruments to collect data. The findings reveal that business English teaching is facilitated and improved through the use of ICTs. The language teachers need special training regarding the practices and implementation of ICTs. It is recommended that initiatives might be taken to equip university language teachers with modern methodology incorporating ICTs as focal area and efforts might be made to remove barriers regarding the training of language teachers and proper usage of ICTs.
Abstract: German electricity European options on futures using
Lévy processes for the underlying asset are examined. Implied
volatility evolution, under each of the considered models, is
discussed after calibrating for the Merton jump diffusion (MJD),
variance gamma (VG), normal inverse Gaussian (NIG), Carr, Geman,
Madan and Yor (CGMY) and the Black and Scholes (B&S) model.
Implied volatility is examined for the entire sample period, revealing
some curious features about market evolution, where data fitting
performances of the five models are compared. It is shown that
variance gamma processes provide relatively better results and that
implied volatility shows significant differences through time, having
increasingly evolved. Volatility changes for changed uncertainty, or
else, increasing futures prices and there is evidence for the need to
account for seasonality when modelling both electricity spot/futures
prices and volatility.
Abstract: The fast growth in complexity coupled with requests for shorter development periods for embedded systems are bringing demands towards a more effective, i.e. higher-abstract, design process for hardaware/software integrated design. In Software Engineering area, Model Driven Architecture (MDA) and Executable UML (xUML) has been accepted to bring further improvement in software design. This paper constructs MDA and xUML stepwise transformations from an abstract specification model to a more concrete implementation model using the refactoring technique for hardaware/software integrated design. This approach provides clear and structured models which enables quick exploration and synthesis, and early stage verification.
Abstract: Mobile learning (M-learning) integrates mobile
devices and wireless computing technology to enhance the current
conventional learning system. However, there are constraints which
are affecting the implementation of platform and device independent
M-learning. The main aim of this research is to fulfill the following
main objectives: to develop platform independent mobile learning
tool (M-LT) for structured programming course, and evaluate its
effectiveness and usability using ADDIE instructional design model
(ISD) as M-LT life cycle. J2ME (Java 2 micro edition) and XML
(Extensible Markup Language) were used to develop platform
independent M-LT. It has two modules lecture materials and quizzes.
This study used Quasi experimental design to measure effectiveness
of the tool. Meanwhile, questionnaire is used to evaluate the usability
of the tool. Finally, the results show that the system was effective and
also usability evaluation was positive.
Abstract: Based on different experiences in the historic centers
of Spain, we propose an global strategy for the regeneration of the
pre-tertiary fabrics and its application to the specific case of San
Mateo neighborhood, in Jerez de la Frontera (Andalusia), through a
diagnosis that focus particularly on the punishments the last-decade
economic situation (building boom and crisis) and shows the tragic
transition from economic center to an imminent disappearance with
an image similar to the ruins of war, due to the loss of their
traditional roles. From it we will learn their historically-tested
mechanisms of environment adaptation, which distill the vernacular
architecture essence and that we will apply to our strategy of action
based on a dotacional-and-free-space rhizome which rediscovers its
hidden character. The architectural fact will be crystallized in one of
the example-pieces proposed: The Artistic Revitalization Center.
Abstract: Hybrid photovoltaic thermal (PV/T) solar system comprises a solar collector which is disposed on photovoltaic solar cells. The disadvantage of a conventional photovoltaic cell is that its performance decreases as the temperature increases. Indeed, part of the solar radiation is converted into electricity and is dissipated as heat, increasing the temperature of the photovoltaic cell with respect to the ambient temperature. The objective of this work is to study experimentally and implement a hybrid prototype to evaluate electrical and thermal performance. In this paper, an experimental study of two new configurations of hybrid collectors is exposed. The results are given and interpreted. The two configurations of absorber studied are a new combination with tubes and galvanized tank, the other is a tubes and sheet.
Abstract: This study presents energy saving in general-purpose
pumps widely used in industrial applications. Such pumps are
normally driven by a constant-speed electrical motor which in most
applications must support varying load conditions. This is equivalent
to saying the loading conditions mismatch the designed optimal
energy consumption requirements of the intended application thus
resulting in substantial energy losses. In the held experiments it was
indicated that combination of mechanical and electrical speed drives
can contribute to lower energy consumption in the pump without
negatively distorting the required performance indices of a typical
centrifugal pump at substantially lower energy consumption. The
registered energy savings were recorded to be within the 15-40%
margin. It was also indicated that although VSDs are installed at a
cost, the financial burden is balanced against the earnings resulting
from the associated energy savings.
Abstract: Increasing user comfort and reducing operation costs
have always been primary objectives of lighting control strategies in a
building. This paper proposes an architecture of the lighting control
system for a daylit office. The system consists of the lighting
controller, A/D & D/A converter, dimmable LED lights, and the
lighting management software. Verification tests are conducted using
the proposed system specialized for the interior lighting of a open-plan
office. The results showed the proposed architecture of the lighting
system would improve the overall system reliability, lower the system
cost, and provide ease of installation and maintenance.
Abstract: Objective: The objective of this paper is to assess the
hospitals preparedness for emergency using WHO standards.
Method: This is a cross-sectional study, consisted of site visit,
questionnaire survey, 16 health facilities were included. The WHO
standard for emergency preparedness of health facilities was used to
evaluate and assess the hospitals preparedness of health facilities.
Result: 13 hospitals were responded. They scored below average
in all measure >75%), while above average score was in 7 out 9 nine
measure with a range of 8%-25%. Un acceptable below average was
noted in two measures only.
Discussion: The biggest challenge facing the hospitals in their
emergency intervention is the lack of pre-emergency and emergency
preparedness plans as well as the coordination of the hospitals
response mechanisms.
Conclusion: The studied hospitals presently are far from
international disasters preparedness protocols. That necessitates
improvements in emergency preparedness, as well as in physician
skills for injury management.
Abstract: This paper deals with stability analysis for synchronous reluctance motors drive. Special attention is paid to the transient performance with variations in motor's parameters such as Ld and Rs. A study of the dynamic control using d-q model is presented first in order to clarify the stability of the motor drive system. Based on the experimental parameters of the synchronous reluctance motor, this paper gives some simulation results using MATLAB/SIMULINK software packages. It is concluded that the motor parameters, especially Ld, affect the estimator stability and hence the whole drive system.
Abstract: This paper presents a cold flow simulation study of a small gas turbine combustor performed using laboratory scale test rig. The main objective of this investigation is to obtain physical insight of the main vortex, responsible for the efficient mixing of fuel and air. Such models are necessary for predictions and optimization of real gas turbine combustors. Air swirler can control the combustor performance by assisting in the fuel-air mixing process and by producing recirculation region which can act as flame holders and influences residence time. Thus, proper selection of a swirler is needed to enhance combustor performance and to reduce NOx emissions. Three different axial air swirlers were used based on their vane angles i.e., 30°, 45°, and 60°. Three-dimensional, viscous, turbulent, isothermal flow characteristics of the combustor model operating at room temperature were simulated via Reynolds- Averaged Navier-Stokes (RANS) code. The model geometry has been created using solid model, and the meshing has been done using GAMBIT preprocessing package. Finally, the solution and analysis were carried out in a FLUENT solver. This serves to demonstrate the capability of the code for design and analysis of real combustor. The effects of swirlers and mass flow rate were examined. Details of the complex flow structure such as vortices and recirculation zones were obtained by the simulation model. The computational model predicts a major recirculation zone in the central region immediately downstream of the fuel nozzle and a second recirculation zone in the upstream corner of the combustion chamber. It is also shown that swirler angles changes have significant effects on the combustor flowfield as well as pressure losses.
Abstract: The paper explores the development of an optimization of method and apparatus for retrieving extended high dynamic range from digital negative image. Architectural photo imaging can benefit from high dynamic range imaging (HDRI) technique for preserving and presenting sufficient luminance in the shadow and highlight clipping image areas. The HDRI technique that requires multiple exposure images as the source of HDRI rendering may not be effective in terms of time efficiency during the acquisition process and post-processing stage, considering it has numerous potential imaging variables and technical limitations during the multiple exposure process. This paper explores an experimental method and apparatus that aims to expand the dynamic range from digital negative image in HDRI environment. The method and apparatus explored is based on a single source of RAW image acquisition for the use of HDRI post-processing. It will cater the optimization in order to avoid and minimize the conventional HDRI photographic errors caused by different physical conditions during the photographing process and the misalignment of multiple exposed image sequences. The study observes the characteristics and capabilities of RAW image format as digital negative used for the retrieval of extended high dynamic range process in HDRI environment.