Abstract: This paper presents the findings from a numerical simulation of the flow in 37-rod fuel assembly models spaced by a double-wire trapezoidal wrapping as applied to the BREST-OD-300 experimental nuclear reactor. Data on a high static pressure distribution within the models, and equations for determining the fuel bundle flow friction factors have been obtained. Recommendations are provided on using the closing turbulence models available in the ANSYS Fluent. A comparative analysis has been performed against the existing empirical equations for determining the flow friction factors. The calculated and experimental data fit has been shown.
An analysis into the experimental data and results of the numerical simulation of the BREST-OD-300 fuel rod assembly hydrodynamic performance are presented.
Abstract: This investigation develops a revisable method for estimating the estimate value of equivalent 10 Hz voltage flicker (DV10) of a DC Electric Arc Furnace (EAF). This study also discusses three 161kV DC EAFs by field measurement, with those results indicating that the estimated DV10 value is significantly smaller than the survey value. The key point is that the conventional means of estimating DV10 is inappropriate. There is a main cause as the assumed Qmax is too small.
Although DC EAF is regularly operated in a constant MVA mode, the reactive power variation in the Main Transformer (MT) is more significant than that in the Furnace Transformer (FT). A substantial difference exists between estimated maximum reactive power fluctuation (DQmax) and the survey value from actual DC EAF operations. However, this study proposes a revisable method that can obtain a more accurate DV10 estimate than the conventional method.
Abstract: Time base maintenance (TBM) is conventionally applied by the power utilities to maintain circuit breakers (CBs), transformers, bus bars and cables, which may result in under maintenance or over maintenance. As information and communication technology (ICT) industry develops, the maintenance policies of many power utilities have gradually changed from TBM to condition base maintenance (CBM) to improve system operating efficiency, operation cost and power supply reliability. This paper discusses the feasibility of using intelligent electronic devices (IEDs) to construct a CB CBM management platform. CBs in power substations can be monitored using IEDs with additional logic configuration and wire connections. The CB monitoring data can be sent through intranet to a control center and be analyzed and integrated by the Elipse Power Studio software. Finally, a human-machine interface (HMI) of supervisory control and data acquisition (SCADA) system can be designed to construct a CBM management platform to provide maintenance decision information for the maintenance personnel, management personnel and CB manufacturers.
Abstract: Effect of blockage ratio on heat transfer from non-circular tube is studied experimentally. For doing this experiment a suction type low speed wind tunnel with test section dimension of 14×14×40 and velocity in rage of 7-20 m/s was designed. The blockage ratios varied between 1.5 to 7 and Reynolds number based on equivalent diameter varies in range of 7.5×103 to 17.5×103. The results show that by increasing blockage ratio from 1.5 to 7, drag coefficient of the cam shaped tube decreased about 55 percent. By increasing Reynolds number, Nusselt number of the cam shaped tube increases about 40 to 48 percent in all ranges of blockage ratios.
Abstract: Cloud virtualization technologies are becoming more
and more prevalent, cloud users usually encounter the problem of how
to access to the virtualized remote desktops easily over the web
without requiring the installation of special clients. To resolve this
issue, we took advantage of the HTML5 technology and developed
web-based remote desktop. It permits users to access the terminal
which running in our cloud platform from anywhere. We implemented
a sketch of web interface following the cloud computing concept that
seeks to enable collaboration and communication among users for
high performance computing. Given the development of remote
desktop virtualization, it allows to shift the user’s desktop from the
traditional PC environment to the cloud platform, which is stored on a
remote virtual machine rather than locally. This proposed effort has
the potential to positively provide an efficient, resilience and elastic
environment for online cloud service. This is also made possible by the
low administrative costs as well as relatively inexpensive end-user
terminals and reduced energy expenses.
Abstract: Intrabody communication (IBC) is a new way of transferring data using human body as a medium. Minute current can travel though human body without any harm. IBC can remove electrical wires for human area network. IBC can be also a secure communication network system unlike wireless networks which can be accessed by anyone with bad intentions. One of the IBC systems is based on frequency shift keying modulation where individual data are transmitted to the external devices for the purpose of secure access such as digital door lock. It was found that the quality of IBC data transmission was heavily dependent on ground configurations of electronic circuits. Reliable IBC transmissions were not possible when both of the transmitter and receiver used batteries as circuit power source. Transmission was reliable when power supplies were used as power source for both transmitting and receiving sites because the common ground was established through the grounds of instruments such as power supply and oscilloscope. This was due to transmission dipole size and the ground effects of floor and AC power line. If one site used battery as power source and the other site used the AC power as circuit power source, transmission was possible.
Abstract: Both knowledge economy and sustainable development are considered key dimensions in the policy action lines of many developed and developing countries. In this context, universities and other higher education institutes have a vital role in developing and sustaining wellbeing communities.
In this paper, the authors’ aim is to address the links between the concepts of innovation and entrepreneurial capacity and knowledge economy, and to utilize the approach of intellectual capital development in building a sustainable knowledge economy.
The paper will contribute to two discourses:
Developing a common understanding of the intersection aspects between the three concepts: Knowledge economy, Innovation and entrepreneurial system, and sustainable development.
Paving the road towards developing an integrated multidimensional framework for sustainable knowledge economy.
Abstract: The scope of this paper is to evaluate and compare the potential of LS-PV(Large Scale Photovoltaic Power Plant) power generation systems in the southern region of Libya at Al-Kufra for both stationary and tracking systems. A Microsoft Excel-VBA program has been developed to compute slope radiation, dew-point, sky temperature, and then cell temperature, maximum power output and module efficiency of the system for stationary system and for tracking system. The results for energy production show that the total energy output is 114GWh/year for stationary system and 148GWh/year for tracking system. The average module efficiency for the stationary system is 16.6% and 16.2% for the tracking system.
The values of electricity generation capacity factor (CF) and solar capacity factor (SCF) for stationary system were found to be 26% and 62.5% respectively and 34% and 82% for tracking system. The GCR (Ground Cover Ratio) for a stationary system is 0.7, which corresponds to a tilt angle of 24°. The GCR for tracking system was found to be 0.12. The estimated ground area needed to build a 50MW PV plant amounts to approx. 0.55km2 for a stationary PV field constituted by HIT PV arrays and approx. 91MW/ km2. In case of a tracker PV field, the required ground area amounts approx.2.4km2 and approx. 20.5MW/ km2.
Abstract: The present study is an analysis of the forced convection heat transfer in porous channel with an oriented jet at the inlet with uniform velocity and temperature distributions. The upper wall is insulated when the bottom one is kept at constant temperature higher than that of the fluid at the entrance. The dynamic field is analysed by the Brinkman-Forchheimer extended Darcy model and the thermal field is traduced by the energy one equation model. The numerical solution of the governing equations is obtained by using the finite volume method. The results mainly concern the effect of Reynolds number, jet angle and thermal conductivity ratio on the flow structure and local and average Nusselt numbers evolutions.
Abstract: A meta-analysis may be performed using aggregate data (AD) or an individual patient data (IPD). In practice, studies may be available at both IPD and AD level. In this situation, both the IPD and AD should be utilised in order to maximize the available information. Statistical advantages of combining the studies from different level have not been fully explored. This study aims to quantify the statistical benefits of including available IPD when conducting a conventional summary-level meta-analysis. Simulated meta-analysis were used to assess the influence of the levels of data on overall meta-analysis estimates based on IPD-only, AD-only and the combination of IPD and AD (mixed data, MD), under different study scenario. The percentage relative bias (PRB), root mean-square-error (RMSE) and coverage probability were used to assess the efficiency of the overall estimates. The results demonstrate that available IPD should always be included in a conventional meta-analysis using summary level data as they would significantly increased the accuracy of the estimates.On the other hand, if more than 80% of the available data are at IPD level, including the AD does not provide significant differences in terms of accuracy of the estimates. Additionally, combining the IPD and AD has moderating effects on the biasness of the estimates of the treatment effects as the IPD tends to overestimate the treatment effects, while the AD has the tendency to produce underestimated effect estimates. These results may provide some guide in deciding if significant benefit is gained by pooling the two levels of data when conducting meta-analysis.
Abstract: The purpose of this study was to investigate the relationships among leisure motivation, leisure attitude, and health promotion lifestyle. The participants were recruited from a convenience sampling that subjects were at least 55 years of age in Tainan City, Taiwan. Three hundred survey instruments were distributed, and 227 effective instruments were returned, for an effective rate of 75.7%. The collected data were analyzed statistically. The findings of this research were as follows: 1.There is significantly correlated between leisure motivation and leisure attitude. 2. There is significantly correlated between leisure attitude and health promotion lifestyle. 3. There is significantly correlated between leisure motivation and health promotion lifestyle.
Abstract: Banana pseudo-stem and fruit-bunch-stem are
agricultural residues that can be used for conversion to bio-char, biooil,
and gases by using thermochemical process. The aim of this work
is to characterize banana pseudo-stem and banana fruit-bunch-stem
through proximate analysis, elemental analysis, chemical analysis,
thermo-gravimetric analysis, and heating calorific value. The ash
contents of the banana pseudo-stem and banana fruit-bunch-stem are
11.0 mf wt.% and 20.6 mf wt.%; while the carbon content of banana
pseudo-stem and fruit-bunch-stem are 37.9 mf wt.% and 35.58 mf
wt.% respectively. The molecular formulas for banana stem and
banana fruit-bunch-stem are C24H33NO26 and C19H29NO33
respectively. The measured higher heating values of banana pseudostem
and banana fruit-bunch-stem are 15.5MJ/kg and 12.7 MJ/kg
respectively. By chemical analysis, the lignin, cellulose, and
hemicellulose contents in the samples will also be presented. The
feasibility of the banana wastes to be a feedstock for thermochemical
process in comparison with other biomass will be discussed in this
paper.
Abstract: There have been a lot of efforts and researches undertaken in developing efficient tools for performing several tasks in data mining. Due to the massive amount of information embedded in huge data warehouses maintained in several domains, the extraction of meaningful pattern is no longer feasible. This issue turns to be more obligatory for developing several tools in data mining. Furthermore the major aspire of data mining software is to build a resourceful predictive or descriptive model for handling large amount of information more efficiently and user friendly. Data mining mainly contracts with excessive collection of data that inflicts huge rigorous computational constraints. These out coming challenges lead to the emergence of powerful data mining technologies. In this survey a diverse collection of data mining tools are exemplified and also contrasted with the salient features and performance behavior of each tool.
Abstract: Flanges are widely used for connecting valves, pipes and other industrial devices such as gearboxes. Method of producing a flange has a considerable impact on the manner of their involvement with the industrial engines and gearboxes. By Using die casting instead of sand casting and machining for manufacturing flanges, production speed and dimensional accuracy of the parts increases. Also, in die casting, obtained dimensions are close to final dimensions and hence the need for machining flanges after die casting process decreases which makes a significant savings in raw materials and improves the mechanical properties of flanges. In this paper, a typical die of an industrial helical gearbox flange (size ISO 50) was designed and die casting process for producing this type of flange was simulated using ProCAST software. The results of simulation were used for optimizing die design. Finally, using the results of the analysis, optimized die was built.
Abstract: Non-linear FEM calculations are indispensable when important technical information like operating performance of a rubber component is desired. Rubber bumpers built into air-spring structures may undergo large deformations under load, which in itself shows non-linear behavior. The changing contact range between the parts and the incompressibility of the rubber increases this non-linear behavior further. The material characterization of an elastomeric component is also a demanding engineering task. In this paper a comprehensive investigation is introduced including laboratory measurements, mesh density analysis and complex finite element simulations to obtain the load-displacement curve of the chosen rubber bumper. Contact and friction effects are also taken into consideration. The aim of this research is to elaborate a FEM model which is accurate and competitive for a future shape optimization task.
Abstract: Power quality has become a very important issue recently due to the impact on electricity suppliers, equipment manufacturers and customers. Power quality is described as the variation of voltage, current and frequency in a power system. Voltage magnitude is one of the major factors that determine the quality of power. Indeed, custom power technology, the low-voltage counterpart of the more widely known flexible ac transmission system (FACTS) technology, aimed at high-voltage power transmission applications, has emerged as a credible solution to solve many problems relating to power quality problems. There are various power quality problems such as voltage sags, swells, flickers, interruptions and harmonics etc. Active Power Filter (APF) is one of the custom power devices and can mitigate harmonics, reactive power and unbalanced load currents originating from load side. In this study, an extensive review of APF studies, the advantages and disadvantages of each introduced methods are presented. The study also helps the researchers to choose the optimum control techniques and power circuit configuration for APF applications.
Abstract: Although several factors that affect learning to
program have been identified over the years, there continues to be no
indication of any consensus in understanding why some students learn
to program easily and quickly while others have difficulty. Seldom
have researchers considered the problem of how to help the students
enhance the programming learning outcome. The research had been
conducted at a high school in Taiwan. Students participating in the
study consist of 330 tenth grade students enrolled in the Basic
Computer Concepts course with the same instructor. Two types of
training methods-instruction-oriented and exploration-oriented were
conducted. The result of this research shows that the
instruction-oriented training method has better learning performance
than exploration-oriented training method.
Abstract: This study aimed to analyse the application of
sufficiency economy in students’ ways of life on campus at Suan
Sunandha Rajabhat University. Data was gathered through 394
questionnaires. The study results found that the majority of students
were confident that “where there’s a will, there’s a way.” Overall, the
students applied the sufficiency economy at a great level, along with
being persons who do not exploit others, were satisfied with living
their lives moderately, according to the sufficiency economy.
Importance was also given to kindness and generosity. Importantly,
students were happy with living according to their individual
circumstances and status at the present. They saw the importance of
joint life planning, self-development, and self-dependence, always
learning to be satisfied with “adequate”. As for their practices and
ways of life, socially relational activities rated highly, especially
initiation activities for underclassmen at the university and the
seniority system, which are suitable for activities on campus.
Furthermore, the students knew how to build a career and find
supplemental income, knew how to earnestly work according to
convention to finish work, and preferred to study elective subjects
which directly benefit career-wise. The students’ application of
sufficiency economy philosophy principles depended on their lives in
their hometowns. The students from the provinces regularly applied
sufficiency economy philosophy to their lives, for example, by being
frugal, steadfast, determined, avoiding negligence, and making
economical spending plans; more so than the students from the
capital.
Abstract: We installed solar panels and digital meteorological equipments whose electrical power is supplied using PV on July 13, 2011. Then, the relationship between the electric power generation and the irradiation, air temperature, and wind velocity was investigated on a roof at a university. The electrical power generation, irradiation, air temperature, and wind velocity were monitored over two years. By analyzing the measured meteorological data and electric power generation data using PTC, we calculated the size of the solar panel that is most suitable for this system. We also calculated the wasted power generation using PTC with the measured meteorological data obtained in this study. In conclusion, to reduce the "wasted power generation", a smaller-size solar panel is required for stable operation.
Abstract: Search is the most obvious application of information
retrieval. The variety of widely obtainable biomedical data is
enormous and is expanding fast. This expansion makes the existing
techniques are not enough to extract the most interesting patterns
from the collection as per the user requirement. Recent researches are
concentrating more on semantic based searching than the traditional
term based searches. Algorithms for semantic searches are
implemented based on the relations exist between the words of the
documents. Ontologies are used as domain knowledge for identifying
the semantic relations as well as to structure the data for effective
information retrieval. Annotation of data with concepts of ontology is
one of the wide-ranging practices for clustering the documents. In
this paper, indexing based on concept and annotation are proposed
for clustering the biomedical documents. Fuzzy c-means (FCM)
clustering algorithm is used to cluster the documents. The
performances of the proposed methods are analyzed with traditional
term based clustering for PubMed articles in five different diseases
communities. The experimental results show that the proposed
methods outperform the term based fuzzy clustering.