Search results for: local contrast.
451 Exemplary Practice: A Case Study of One of New Zealand’s Most Successful Enterprise Education Teachers
Authors: K. Lee
Abstract:
Many teachers are experienced; however, experience does not necessarily equate to excellence. Excellence in teaching is the single most powerful influence on student achievement. This qualitative, interpretivist case study investigates the practices of one of the nation’s most acknowledged teachers in enterprise education. In a number of semi-structured interviews, and observational visits, this remote regional teacher talked freely about what skills and strategies she used to achieve this success. Findings from this study were compared to key ideas developed by Professor John Hattie with regards to differences between expert, excellent and experienced teachers. Key findings showed the ‘expert teacher’ central to this study; ensured learning was engaging, challenging yet achievable for all (for both teacher and student of all abilities), authentic and driven by local needs, involved community supports; and ensured the process and learning was constantly monitored and teaching adjusted accordingly. It is anticipated that the data collected via observations, semi-structured interviews, and document analysis will help others to support students to gain greater success (in whatever form that may take).
Keywords: Expert teacher, enterprise education, excellence, skills and strategies.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 294450 Causal Factors Affecting on Trustworthiness and Success of the National Press Council of Thailand in Regulating Professional Ethics in Views of Newspaper Journalists
Authors: Bubpha Makesrithongkum
Abstract:
The objectives of this research were 1) to study the opinions of newspaper journalists about their trustworthiness in the National Press Council of Thailand (NPCT) and the NPCT-s success in regulating the professional ethics; and 2) to study the differences among mean vectors of the variables of trustworthiness in the NPCT and opinions on the NPCT-s success in regulating professional ethics among samples working at different work positions and from different affiliation of newspaper organizations. The results showed that 1) Interaction effects between the variables of work positions and affiliation were not statistically significant at the confidence level of 0.05. 2) There was a statistically significant difference (p<0.05) in the views of journalists (reporters, heads of news desks and editors) at newspapers in the Bangkok metropolis and at local newspapers in other regions regarding their level of trustworthiness in the NPCT-s fulfillment of its duty to regulate professional ethics.Keywords: National Press Council of Thailand, newspaper journalists, regulation of newspaper professional ethics, trustworthiness and success in fulfilling duties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1567449 Analysis of the Root Causes of Transformer Bushing Failures
Authors: E. A. Feilat, I. A. Metwally, S. Al-Matri, A. S. Al-Abri
Abstract:
This paper presents the results of a comprehensive investigation of five blackouts that occurred on 28 August to 8 September 2011 due to bushing failures of the 132/33 kV, 125 MVA transformers at JBB Ali Grid station. The investigation aims to explore the root causes of the bushing failures and come up with recommendations that help in rectifying the problem and avoiding the reoccurrence of similar type of incidents. The incident reports about the failed bushings and the SCADA reports at this grid station were examined and analyzed. Moreover, comprehensive power quality field measurements at ten 33/11 kV substations (S/Ss) in JBB Ali area were conducted, and frequency scans were performed to verify any harmonic resonance frequencies due to power factor correction capacitors. Furthermore, the daily operations of the on-load tap changers (OLTCs) of both the 125 MVA and 20 MVA transformers at JBB Ali Grid station have been analyzed. The investigation showed that the five bushing failures were due to a local problem, i.e. internal degradation of the bushing insulation. This has been confirmed by analyzing the time interval between successive OLTC operations of the faulty grid transformers. It was also found that monitoring the number of OLTC operations can help in predicting bushing failure.Keywords: Modeling and simulation, power system, transformer, bushing, OLTC, power quality, partial discharge.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10752448 Efficient Numerical Model for Studying Bridge Pier Collapse in Floods
Authors: Thanut Kallaka, Ching-Jong Wang
Abstract:
High level and high velocity flood flows are potentially harmful to bridge piers as evidenced in many toppled piers, and among them the single-column piers were considered as the most vulnerable. The flood flow characteristic parameters including drag coefficient, scouring and vortex shedding are built into a pier-flood interaction model to investigate structural safety against flood hazards considering the effects of local scouring, hydrodynamic forces, and vortex induced resonance vibrations. By extracting the pier-flood simulation results embedded in a neural networks code, two cases of pier toppling occurred in typhoon days were reexamined: (1) a bridge overcome by flash flood near a mountain side; (2) a bridge washed off in flood across a wide channel near the estuary. The modeling procedures and simulations are capable of identifying the probable causes for the tumbled bridge piers during heavy floods, which include the excessive pier bending moments and resonance in structural vibrations.Keywords: Bridge piers, Neural networks, Scour depth, Structural safety, Vortex shedding
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2252447 Thai Student Ability on Speexx Language Training Program
Authors: Toby Gibbs, Glen Craigie, Suwaree Yordchim
Abstract:
The Speexx results revealed four main factors affecting the success of 190 Thai sophomores as follows: 1) Future English training should be pursued in applied Speexx development. 2) Thai students didn’t see the benefit of having an Online Language Training Program. 3) There is a great need to educate the next generation of learners on the benefits of Speexx within the community. 4) A great majority of Thai Sophomores didn't know what Speexx was. A guideline for self-reliance planning consisted of four aspects: 1) Development planning: by arranging groups to further improve English abilities with the Speexx Language Training program and encourage using Speexx into every day practice. Local communities need to develop awareness of the usefulness of Speexx and share the value of using the program among family and friends. 2) Humanities and Social Science staff should develop skills using this Online Language Training Program to expand on the benefits of Speexx within their departments. 3) Further research should be pursued on the Thai Students progression with Speexx and how it helps them improve their language skills with Business English. 4) University’s and Language centers should focus on using Speexx to encourage learning for any language, not just English.Keywords: Ability, Comprehension, Sophomore, Speexx.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2399446 Effects of Road Disturbance on Plant Biodiversity
Authors: Sheng-Lan Zeng, Ting-Ting Zhang, Yu Gao, Zu-Tao Ouyang, Jia-Kuan Chen, Bo Li, Bin Zhao
Abstract:
Urbanization and related anthropogenic modifications cause extent of habitat fragmentation and directly lead to decline of local biodiversity. Conservation biologists advocate corridor creation as one approach to rescue biodiversity. Here we examine the utility of roads as corridors in preserving plant diversity by investigating roadside vegetation in Yellow River Delta (YRD), China. We examined the spatio-temporal distribution pattern of plant species richness, diversity and composition along roadside. The results suggest that roads, as dispersal conduits, increase occurrence probability of new settlers to a new area, meanwhile, roads accumulate the greater propagule pressure and favourable survival condition during operation phase. As a result, more species, including native and alien plants, non- halophyte and halophyte species, threatened and cosmopolitic species, were found prosperous at roadside. Roadside may be a refuge for more species, and the pattern of vegetation distribution is affected by road age and the distance from road verge.Keywords: Native and alien species, Plant diversity conservation, Road construction, Road disturbance
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3517445 Assessment of Agricultural Land Use Land Cover, Land Surface Temperature and Population Changes Using Remote Sensing and GIS: Southwest Part of Marmara Sea, Turkey
Authors: Melis Inalpulat, Levent Genc
Abstract:
Land Use Land Cover (LULC) changes due to human activities and natural causes have become a major environmental concern. Assessment of temporal remote sensing data provides information about LULC impacts on environment. Land Surface Temperature (LST) is one of the important components for modeling environmental changes in climatological, hydrological, and agricultural studies. In this study, LULC changes (September 7, 1984 and July 8, 2014) especially in agricultural lands together with population changes (1985-2014) and LST status were investigated using remotely sensed and census data in South Marmara Watershed, Turkey. LULC changes were determined using Landsat TM and Landsat OLI data acquired in 1984 and 2014 summers. Six-band TM and OLI images were classified using supervised classification method to prepare LULC map including five classes including Forest (F), Grazing Land (G), Agricultural Land (A), Water Surface (W), Residential Area-Bare Soil (R-B) classes. The LST image was also derived from thermal bands of the same dates. LULC classification results showed that forest areas, agricultural lands, water surfaces and residential area-bare soils were increased as 65751 ha, 20163 ha, 1924 ha and 20462 ha respectively. In comparison, a dramatic decrement occurred in grazing land (107985 ha) within three decades. The population increased 29% between years 1984-2014 in whole study area. Along with the natural causes, migration also caused this increase since the study area has an important employment potential. LULC was transformed among the classes due to the expansion in residential, commercial and industrial areas as well as political decisions. In the study, results showed that agricultural lands around the settlement areas transformed to residential areas in 30 years. The LST images showed that mean temperatures were ranged between 26-32°C in 1984 and 27-33°C in 2014. Minimum temperature of agricultural lands was increased 3°C and reached to 23°C. In contrast, maximum temperature of A class decreased to 41°C from 44°C. Considering temperatures of the 2014 R-B class and 1984 status of same areas, it was seen that mean, min and max temperatures increased by 2°C. As a result, the dynamism of population, LULC and LST resulted in increasing mean and maximum surface temperatures, living spaces/industrial areas and agricultural lands.Keywords: Census data, landsat, land surface temperature (LST), land use land cover (LULC).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2106444 Biomass and Productivity Studies of Up-Land and Low-Land Vegetation in the Neglected Margin of a Tropical Lake
Authors: Mayank Singh, O. P. Singh ‘Vatsa’, M. P. Singh
Abstract:
Present paper deals with an evaluation of magnitude of changes in biomass and net primary productivity at ‘Gujar Tal’ sloppy lake margin at Jaunpur in tropical semi-arid region of eastern U.P. (India). The study site abandoned or neglected lands (50 ×125 m) was divided into two zones, i.e. upper zone (up-land) and lower zone (low-land). Maximum biomass in the upper zone of dominant weed Desmostachya bipinnata (L.) Stapf. was 207.47 g m-2 and ‘rest weeds’ was 457.45 g m-2 both in the month of September. In contrast, the peak biomass value in the lower zone of dominant weed Oryza rufipogon Griff. was 1571.44 g m-2 in October and ‘rest weeds’ 270.65 g m-2 in February. Among the two zones, the peak total community biomass was observed 1655.62 g m-2 (October) in the lower zone while its peak value for the upper zone 457.45 g m-2 (September) was comparatively low. Maximum percentage contribution of dominant weeds (D. bipinnata and O. rufipogon) in the respective upper and lower zones and ‘rest weeds’ in both the zones varied in different months in the total community biomass. The peak net primary productivity of dominant weed (D. bipinnata) was 2.09g m-2 day-1 (September) and ‘rest weeds’ was 2.37 g m-2 day-1 (August) in the upper zone, while the lower zone for O. rufipogon was 5.25 g m-2 day-1 (June) as this zone was inundated later and ‘rest weeds’ was 2.08 g m-2 day-1 (January, 2009). The annual net production of total community at site I was highest, 409.58 g m-2 yr-1 in the upper zone followed by 395.58 g m-2 per eight month in the lower zone as this zone was flooded with water during rainy season. The site significance of variations in biomass in relation to plant species was tested by analysis of variance. It was significant between months in all the two zones (p<0.01 and p<0.05).
Keywords: Biomass, Neglected Lake Margin, Productivity, Vegetation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1717443 Numerical Analysis of Laminar Flow around Square Cylinders with EHD Phenomenon
Authors: M. Salmanpour, O. Nourani Zonouz
Abstract:
In this research, a numerical simulation of an Electrohydrodynamic (EHD) actuator’s effects on the flow around a square cylinder by using a finite volume method has been investigated. This is one of the newest ways for controlling the fluid flows. Two plate electrodes are flush-mounted on the surface of the cylinder and one wire electrode is placed on the line with zero angle of attack relative to the stagnation point and excited with DC power supply. The discharge produces an electric force and changes the local momentum behaviors in the fluid layers. For this purpose, after selecting proper domain and boundary conditions, the electric field relating to the problem has been analyzed and then the results in the form of electrical body force have been entered in the governing equations of fluid field (Navier-Stokes equations). The effect of ionic wind resulted from the Electrohydrodynamic actuator, on the velocity, pressure and the wake behind cylinder has been considered. According to the results, it is observed that the fluid flow accelerates in the nearest wall of the frontal half of the cylinder and the pressure difference between frontal and hinder cylinder is increased.
Keywords: CFD, corona discharge, electro hydrodynamics, flow around square cylinders.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 868442 Modelling the Photovoltaic Pump Output Using Empirical Data from Local Conditions in the Vhembe District
Authors: C. Matasane, C. Dwarika, R. Naidoo
Abstract:
The mathematical analysis on radiation obtained and the development of the solar photovoltaic (PV) array groundwater pumping is needed in the rural areas of Thohoyandou for sizing and power performance subject to the climate conditions within the area. A simple methodology approach is developed for the directed coupled solar, controller and submersible ground water pump system. The system consists of a PV array, pump controller and submerged pump, battery backup and charger controller. For this reason, the theoretical solar radiation is obtained for optimal predictions and system performance in order to achieve different design and operating parameters. Here the examination of the PV schematic module in a Direct Current (DC) application is used for obtainable maximum solar power energy for water pumping. In this paper, a simple efficient photovoltaic water pumping system is presented with its theoretical studies and mathematical modeling of photovoltaics (PV) system.
Keywords: Renewable energy sources, solar groundwater pumping, theoretical and mathematical analysis of photovoltaic (PV) system, theoretical solar radiation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2511441 An Off-the-Shelf Scheme for Dependable Grid Systems Using Virtualization
Authors: Toshinori Takabatake
Abstract:
Recently, grid computing has been widely focused on the science, industry, and business fields, which are required a vast amount of computing. Grid computing is to provide the environment that many nodes (i.e., many computers) are connected with each other through a local/global network and it is available for many users. In the environment, to achieve data processing among nodes for any applications, each node executes mutual authentication by using certificates which published from the Certificate Authority (for short, CA). However, if a failure or fault has occurred in the CA, any new certificates cannot be published from the CA. As a result, a new node cannot participate in the gird environment. In this paper, an off-the-shelf scheme for dependable grid systems using virtualization techniques is proposed and its implementation is verified. The proposed approach using the virtualization techniques is to restart an application, e.g., the CA, if it has failed. The system can tolerate a failure or fault if it has occurred in the CA. Since the proposed scheme is implemented at the application level easily, the cost of its implementation by the system builder hardly takes compared it with other methods. Simulation results show that the CA in the system can recover from its failure or fault.Keywords: grid computing, restarting application, certificate authority, virtualization, dependability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1369440 Trends and Prospects for the Development of Georgian Wine Market
Authors: E. Kharaishvili, M. Chavleishvili, M. Natsvaladze
Abstract:
The article presents the trends in Georgian wine market development and evaluates the competitive advantages of Georgia to enter the wine market based on its customs, traditions and historical practices combined with modern technologies. In order to analyze the supply of wine, dynamics of vineyard land area and grape varieties are discussed, trends in wine production are presented, trends in export and import are evaluated, local wine market, its micro and macro environments are studied and analyzed based on the interviews with experts and analysis of initial recording materials. For strengthening its position on the international market, the level of competitiveness of Georgian wine is defined, which is evaluated by “ex-ante” and “ex-post” methods, as well as by four basic and two additional factors of the Porter’s diamond method; potential advantages and disadvantages of Georgian wine are revealed. Conclusions are made by identifying the factors that hinder the development of Georgian wine market. Based on the conclusions, relevant recommendations are developed.
Keywords: Georgian wine market, competitive advantage, bio wine, export-import, Porter's diamond model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4141439 Depth-Averaged Modelling of Erosion and Sediment Transport in Free-Surface Flows
Authors: Thomas Rowan, Mohammed Seaid
Abstract:
A fast finite volume solver for multi-layered shallow water flows with mass exchange and an erodible bed is developed. This enables the user to solve a number of complex sediment-based problems including (but not limited to), dam-break over an erodible bed, recirculation currents and bed evolution as well as levy and dyke failure. This research develops methodologies crucial to the under-standing of multi-sediment fluvial mechanics and waterway design. In this model mass exchange between the layers is allowed and, in contrast to previous models, sediment and fluid are able to transfer between layers. In the current study we use a two-step finite volume method to avoid the solution of the Riemann problem. Entrainment and deposition rates are calculated for the first time in a model of this nature. In the first step the governing equations are rewritten in a non-conservative form and the intermediate solutions are calculated using the method of characteristics. In the second stage, the numerical fluxes are reconstructed in conservative form and are used to calculate a solution that satisfies the conservation property. This method is found to be considerably faster than other comparative finite volume methods, it also exhibits good shock capturing. For most entrainment and deposition equations a bed level concentration factor is used. This leads to inaccuracies in both near bed level concentration and total scour. To account for diffusion, as no vertical velocities are calculated, a capacity limited diffusion coefficient is used. The additional advantage of this multilayer approach is that there is a variation (from single layer models) in bottom layer fluid velocity: this dramatically reduces erosion, which is often overestimated in simulations of this nature using single layer flows. The model is used to simulate a standard dam break. In the dam break simulation, as expected, the number of fluid layers utilised creates variation in the resultant bed profile, with more layers offering a higher deviation in fluid velocity . These results showed a marked variation in erosion profiles from standard models. The overall the model provides new insight into the problems presented at minimal computational cost.Keywords: Erosion, finite volume method, sediment transport, shallow water equations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 981438 Ethnobotany and Distribution of Wild Edible Tubers in Pulau Redang and Nearby Islands of Terengganu, Malaysia
Authors: M. Nashriyah, M. Y. Nur Athiqah, H. Syahril Amin, N. Norhayati, A. W. Mohamad Azhar, M. Khairil
Abstract:
An ethnobotanical study was conducted to document local knowledge and potentials of wild edible tubers that has been reported and sighted and to investigate and record their distribution in Pulau Redang and nearby islands of Terengganu, Malaysia. Information was gathered from 42 villagers by using semi-structured questionnaire. These respondents were selected randomly and no appointment was made prior to the visits. For distribution, the locations of wild edible tubers were recorded by using the Global Positioning System (GPS). The wild edible tubers recorded were ubi gadung, ubi toyo, ubi kasu, ubi jaga, ubi seratus and ubi kertas. Dioscorea or commonly known as yam is reported to be one of the major food sources worldwide. The majority of villagers used Dioscorea hispida Dennst. or ubi gadung in many ways in their life such as for food, medicinal purposes and fish poison. The villagers have identified this ubi gadung by looking at the morphological characteristics; that include leaf shape, stem and the color of the tuber-s flesh.Keywords: Ethnobotany, distribution, wild edible tubers, Dioscorea hispida Dennst., ubi gadung
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2945437 On the Development of a Homogenized Earthquake Catalogue for Northern Algeria
Authors: I. Grigoratos, R. Monteiro
Abstract:
Regions with a significant percentage of non-seismically designed buildings and reduced urban planning are particularly vulnerable to natural hazards. In this context, the project ‘Improved Tools for Disaster Risk Mitigation in Algeria’ (ITERATE) aims at seismic risk mitigation in Algeria. Past earthquakes in North Algeria caused extensive damages, e.g. the El Asnam 1980 moment magnitude (Mw) 7.1 and Boumerdes 2003 Mw 6.8 earthquakes. This paper will address a number of proposed developments and considerations made towards a further improvement of the component of seismic hazard. In specific, an updated earthquake catalog (until year 2018) is compiled, and new conversion equations to moment magnitude are introduced. Furthermore, a network-based method for the estimation of the spatial and temporal distribution of the minimum magnitude of completeness is applied. We found relatively large values for Mc, due to the sparse network, and a nonlinear trend between Mw and body wave (mb) or local magnitude (ML), which are the most common scales reported in the region. Lastly, the resulting b-value of the Gutenberg-Richter distribution is sensitive to the declustering method.
Keywords: Conversion equation, magnitude of completeness, seismic events, seismic hazard.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 804436 The Gravitational Impact of the Sun and the Moon on Heavy Mineral Deposits and Dust Particles in Low Gravity Regions of the Earth
Authors: T. B. Karu Jayasundara
Abstract:
The Earth’s gravity is not uniform. The satellite imageries of the Earth’s surface from NASA reveal a number of different gravity anomaly regions all over the globe. When the moon rotates around the earth, its gravity has a major physical influence on a number of regions on the earth. This physical change can be seen by the tides. The tides make sea levels high and low in coastal regions. During high tide, the gravitational force of the Moon pulls the Earth’s gravity so that the total gravitational intensity of Earth is reduced; it is further reduced in the low gravity regions of Earth. This reduction in gravity helps keep the suspended particles such as dust in the atmosphere, sand grains in the sea water for longer. Dramatic differences can be seen from the floating dust in the low gravity regions when compared with other regions. The above phenomena can be demonstrated from experiments. The experiments have to be done in high and low gravity regions of the earth during high and low tide, which will assist in comparing the final results. One of the experiments that can be done is by using a water filled cylinder about 80 cm tall, a few particles, which have the same density and same diameter (about 1 mm) and a stop watch. The selected particles were dropped from the surface of the water in the cylinder and the time taken for the particles to reach the bottom of the cylinder was measured using the stop watch. The times of high and low tide charts can be obtained from the regional government authorities. This concept is demonstrated by the particle drop times taken at high and low tides. The result of the experiment shows that the particle settlement time is less in low tide and high in high tide. The experiment for dust particles in air can be collected on filters, which are cellulose ester membranes and using a vacuum pump. The dust on filters can be used to make slides according to the NOHSC method. Counting the dust particles on the slides can be done using a phase contrast microscope. The results show that the concentration of dust is high at high tide and low in low tide. As a result of the high tides, a high concentration of heavy minerals deposit on placer deposits and dust particles retain in the atmosphere for longer in low gravity regions. These conditions are remarkably exhibited in the lowest low gravity region of the earth, mainly in the regions of India, Sri Lanka and in the middle part of the Indian Ocean. The biggest heavy mineral placer deposits are found in coastal regions of India and Sri Lanka and heavy dust particles are found in the atmosphere of India, particularly in the Delhi region.
Keywords: Dust particles, high and low tides, heavy minerals. low gravity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 611435 A Fuzzy Approach to Liver Tumor Segmentation with Zernike Moments
Authors: Abder-Rahman Ali, Antoine Vacavant, Manuel Grand-Brochier, Adélaïde Albouy-Kissi, Jean-Yves Boire
Abstract:
In this paper, we present a new segmentation approach for liver lesions in regions of interest within MRI (Magnetic Resonance Imaging). This approach, based on a two-cluster Fuzzy CMeans methodology, considers the parameter variable compactness to handle uncertainty. Fine boundaries are detected by a local recursive merging of ambiguous pixels with a sequential forward floating selection with Zernike moments. The method has been tested on both synthetic and real images. When applied on synthetic images, the proposed approach provides good performance, segmentations obtained are accurate, their shape is consistent with the ground truth, and the extracted information is reliable. The results obtained on MR images confirm such observations. Our approach allows, even for difficult cases of MR images, to extract a segmentation with good performance in terms of accuracy and shape, which implies that the geometry of the tumor is preserved for further clinical activities (such as automatic extraction of pharmaco-kinetics properties, lesion characterization, etc.).Keywords: Defuzzification, floating search, fuzzy clustering, Zernike moments.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2043434 Numerical Investigation into Mixing Performance of Electrokinetically-Driven Power-Law Fluids in Microchannel with Patterned Trapezoid Blocks
Authors: Cha’o-Kuang Chen, Ching-Chang Cho
Abstract:
The study investigates the mixing performance of electrokinetically-driven power-law fluids in a microchannel containing patterned trapezoid blocks. The effects of the geometry parameters of the patterned trapezoid blocks and the flow behavior index in the power-law model on the mixing efficiency within the microchannel are explored. The results show that the mixing efficiency can be improved by increasing the width of the blocks and extending the length of upper surface of the blocks. In addition, the results show that the mixing efficiency increases with an increasing flow behavior index. Furthermore, it is shown that a heterogeneous patterning of the zeta potential on the upper surfaces of the trapezoid blocks prompts the formation of local flow recirculations, and therefore improves the mixing efficiency. Consequently, it is shown that the mixing performance improves with an increasing magnitude of the heterogeneous surface zeta potential.
Keywords: Non-Newtonian fluid, Power-law fluid, Electroosmotic flow, Passive mixer, Mixing, Micromixer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1505433 A Novel Prostate Segmentation Algorithm in TRUS Images
Authors: Ali Rafiee, Ahad Salimi, Ali Reza Roosta
Abstract:
Prostate cancer is one of the most frequent cancers in men and is a major cause of mortality in the most of countries. In many diagnostic and treatment procedures for prostate disease accurate detection of prostate boundaries in transrectal ultrasound (TRUS) images is required. This is a challenging and difficult task due to weak prostate boundaries, speckle noise and the short range of gray levels. In this paper a novel method for automatic prostate segmentation in TRUS images is presented. This method involves preprocessing (edge preserving noise reduction and smoothing) and prostate segmentation. The speckle reduction has been achieved by using stick filter and top-hat transform has been implemented for smoothing. A feed forward neural network and local binary pattern together have been use to find a point inside prostate object. Finally the boundary of prostate is extracted by the inside point and an active contour algorithm. A numbers of experiments are conducted to validate this method and results showed that this new algorithm extracted the prostate boundary with MSE less than 4.6% relative to boundary provided manually by physicians.
Keywords: Prostate segmentation, stick filter, neural network, active contour.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1958432 A Normalization-based Robust Image Watermarking Scheme Using SVD and DCT
Authors: Say Wei Foo, Qi Dong
Abstract:
Digital watermarking is one of the techniques for copyright protection. In this paper, a normalization-based robust image watermarking scheme which encompasses singular value decomposition (SVD) and discrete cosine transform (DCT) techniques is proposed. For the proposed scheme, the host image is first normalized to a standard form and divided into non-overlapping image blocks. SVD is applied to each block. By concatenating the first singular values (SV) of adjacent blocks of the normalized image, a SV block is obtained. DCT is then carried out on the SV blocks to produce SVD-DCT blocks. A watermark bit is embedded in the highfrequency band of a SVD-DCT block by imposing a particular relationship between two pseudo-randomly selected DCT coefficients. An adaptive frequency mask is used to adjust local watermark embedding strength. Watermark extraction involves mainly the inverse process. The watermark extracting method is blind and efficient. Experimental results show that the quality degradation of watermarked image caused by the embedded watermark is visually transparent. Results also show that the proposed scheme is robust against various image processing operations and geometric attacks.Keywords: Image watermarking, Image normalization, Singularvalue decomposition, Discrete cosine transform, Robustness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2083431 A Force-directed Graph Drawing based on the Hierarchical Individual Timestep Method
Authors: T. Matsubayashi, T. Yamada
Abstract:
In this paper, we propose a fast and efficient method for drawing very large-scale graph data. The conventional force-directed method proposed by Fruchterman and Rheingold (FR method) is well-known. It defines repulsive forces between every pair of nodes and attractive forces between connected nodes on a edge and calculates corresponding potential energy. An optimal layout is obtained by iteratively updating node positions to minimize the potential energy. Here, the positions of the nodes are updated every global timestep at the same time. In the proposed method, each node has its own individual time and time step, and nodes are updated at different frequencies depending on the local situation. The proposed method is inspired by the hierarchical individual time step method used for the high accuracy calculations for dense particle fields such as star clusters in astrophysical dynamics. Experiments show that the proposed method outperforms the original FR method in both speed and accuracy. We implement the proposed method on the MDGRAPE-3 PCI-X special purpose parallel computer and realize a speed enhancement of several hundred times.Keywords: visualization, graph drawing, Internet Map
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1839430 Comparison of Three Turbulence Models in Wear Prediction of Multi-Size Particulate Flow through Rotating Channel
Authors: Pankaj K. Gupta, Krishnan V. Pagalthivarthi
Abstract:
The present work compares the performance of three turbulence modeling approach (based on the two-equation k -ε model) in predicting erosive wear in multi-size dense slurry flow through rotating channel. All three turbulence models include rotation modification to the production term in the turbulent kineticenergy equation. The two-phase flow field obtained numerically using Galerkin finite element methodology relates the local flow velocity and concentration to the wear rate via a suitable wear model. The wear models for both sliding wear and impact wear mechanisms account for the particle size dependence. Results of predicted wear rates using the three turbulence models are compared for a large number of cases spanning such operating parameters as rotation rate, solids concentration, flow rate, particle size distribution and so forth. The root-mean-square error between FE-generated data and the correlation between maximum wear rate and the operating parameters is found less than 2.5% for all the three models.Keywords: Rotating channel, maximum wear rate, multi-sizeparticulate flow, k −ε turbulence models.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1762429 A Hybrid Metaheuristic Framework for Evolving the PROAFTN Classifier
Authors: Feras Al-Obeidat, Nabil Belacel, Juan A. Carretero, Prabhat Mahanti,
Abstract:
In this paper, a new learning algorithm based on a hybrid metaheuristic integrating Differential Evolution (DE) and Reduced Variable Neighborhood Search (RVNS) is introduced to train the classification method PROAFTN. To apply PROAFTN, values of several parameters need to be determined prior to classification. These parameters include boundaries of intervals and relative weights for each attribute. Based on these requirements, the hybrid approach, named DEPRO-RVNS, is presented in this study. In some cases, the major problem when applying DE to some classification problems was the premature convergence of some individuals to local optima. To eliminate this shortcoming and to improve the exploration and exploitation capabilities of DE, such individuals were set to iteratively re-explored using RVNS. Based on the generated results on both training and testing data, it is shown that the performance of PROAFTN is significantly improved. Furthermore, the experimental study shows that DEPRO-RVNS outperforms well-known machine learning classifiers in a variety of problems.Keywords: Knowledge Discovery, Differential Evolution, Reduced Variable Neighborhood Search, Multiple criteria classification, PROAFTN, Supervised Learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1470428 Harris Extraction and SIFT Matching for Correlation of Two Tablets
Authors: Ali Alzaabi, Georges Alquié, Hussain Tassadaq, Ali Seba
Abstract:
This article presents the developments of efficient algorithms for tablet copies comparison. Image recognition has specialized use in digital systems such as medical imaging, computer vision, defense, communication etc. Comparison between two images that look indistinguishable is a formidable task. Two images taken from different sources might look identical but due to different digitizing properties they are not. Whereas small variation in image information such as cropping, rotation, and slight photometric alteration are unsuitable for based matching techniques. In this paper we introduce different matching algorithms designed to facilitate, for art centers, identifying real painting images from fake ones. Different vision algorithms for local image features are implemented using MATLAB. In this framework a Table Comparison Computer Tool “TCCT" is designed to facilitate our research. The TCCT is a Graphical Unit Interface (GUI) tool used to identify images by its shapes and objects. Parameter of vision system is fully accessible to user through this graphical unit interface. And then for matching, it applies different description technique that can identify exact figures of objects.Keywords: Harris Extraction and SIFT Matching
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1728427 MIMO-OFDM Channel Tracking Using a Dynamic ANN Topology
Authors: Manasjyoti Bhuyan, Kandarpa Kumar Sarma
Abstract:
All the available algorithms for blind estimation namely constant modulus algorithm (CMA), Decision-Directed Algorithm (DDA/DFE) suffer from the problem of convergence to local minima. Also, if the channel drifts considerably, any DDA looses track of the channel. So, their usage is limited in varying channel conditions. The primary limitation in such cases is the requirement of certain overhead bits in the transmit framework which leads to wasteful use of the bandwidth. Also such arrangements fail to use channel state information (CSI) which is an important aid in improving the quality of reception. In this work, the main objective is to reduce the overhead imposed by the pilot symbols, which in effect reduces the system throughput. Also we formulate an arrangement based on certain dynamic Artificial Neural Network (ANN) topologies which not only contributes towards the lowering of the overhead but also facilitates the use of the CSI. A 2×2 Multiple Input Multiple Output (MIMO) system is simulated and the performance variation with different channel estimation schemes are evaluated. A new semi blind approach based on dynamic ANN is proposed for channel tracking in varying channel conditions and the performance is compared with perfectly known CSI and least square (LS) based estimation.
Keywords: MIMO, Artificial Neural Network (ANN), CMA, LS, CSI.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2358426 Assessment of Sustainability in the Wulo Abiye Watershed, Central Highlands of Ethiopia
Authors: Getabalew Derib, Arragaw Alemayehu
Abstract:
Assessing the sustainability of watersheds holds significant importance for regional natural resource management and to achieve sustainable development. This study investigated the sustainability of the Wulo Abiye watershed, central highlands of Ethiopia. The sustainability status of the watershed was evaluated by using 17 indicators representing the economic, social, and environmental dimensions of sustainable development goals (SDGs) based on the local and existing conditions of the watershed. The results indicated that environmental sustainability was at a ‘high’ level, while social and economic sustainability and the aggregate index were at ‘moderate’ levels. The overall level of community participation in the planning and evaluation phases of watershed management was at ‘low’ levels. The implementation phase was at ‘high’ level. Overall, the sustainability status of the watershed management practices and the level of community participation were at a moderate level. The study concluded that integrated support is needed to overcome the identified challenges to achieve sustainable development in watersheds.
Keywords: Wulo Abiye watershed, community participation, watershed management, sustainable development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30425 Lack of BIM Training: Investigating Practical Solutions for the State of Kuwait
Authors: Noor M. Abdulfattah, Ahmed M. Khalafallah, Nabil A. Kartam
Abstract:
Despite the evident benefits of building information modeling (BIM) to the construction industry, it faces significant implementation challenges in the State of Kuwait. This study investigates the awareness of construction stakeholders of BIM implementation challenges, and identifies various solutions to overcome these challenges. Specifically, the main objectives of this study are to: (1) characterize the barriers that deter utilization of BIM, (2) examine the awareness of engineers, architects, and construction stakeholders of these barriers, and (3) identify practical solutions to facilitate BIM utilization. A questionnaire survey was designed to collect data on the aforementioned objectives from local companies and senior BIM experts. It was found that engineers are highly aware of BIM implementation barriers. In addition, it was concluded from the questionnaire that the biggest barrier is the lack of BIM training. Based on expert feedback, the study concluded with a number of recommendations on how to overcome the barriers of BIM utilization. This should prove useful to the construction industry stakeholders and can lead to significant changes to design and construction practices.
Keywords: Building information modeling, construction, challenges, information technology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2458424 Gray Level Image Encryption
Authors: Roza Afarin, Saeed Mozaffari
Abstract:
The aim of this paper is image encryption using Genetic Algorithm (GA). The proposed encryption method consists of two phases. In modification phase, pixels locations are altered to reduce correlation among adjacent pixels. Then, pixels values are changed in the diffusion phase to encrypt the input image. Both phases are performed by GA with binary chromosomes. For modification phase, these binary patterns are generated by Local Binary Pattern (LBP) operator while for diffusion phase binary chromosomes are obtained by Bit Plane Slicing (BPS). Initial population in GA includes rows and columns of the input image. Instead of subjective selection of parents from this initial population, a random generator with predefined key is utilized. It is necessary to decrypt the coded image and reconstruct the initial input image. Fitness function is defined as average of transition from 0 to 1 in LBP image and histogram uniformity in modification and diffusion phases, respectively. Randomness of the encrypted image is measured by entropy, correlation coefficients and histogram analysis. Experimental results show that the proposed method is fast enough and can be used effectively for image encryption.
Keywords: Correlation coefficients, Genetic algorithm, Image encryption, Image entropy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2228423 Educational Knowledge Transfer in Indigenous Mexican Areas Using Cloud Computing
Authors: L. R. Valencia Pérez, J. M. Peña Aguilar, A. Lamadrid Álvarez, A. Pastrana Palma, H. F. Valencia Pérez, M. Vivanco Vargas
Abstract:
This work proposes a Cooperation-Competitive (Coopetitive) approach that allows coordinated work among the Secretary of Public Education (SEP), the Autonomous University of Querétaro (UAQ) and government funds from National Council for Science and Technology (CONACYT) or some other international organizations. To work on an overall knowledge transfer strategy with e-learning over the Cloud, where experts in junior high and high school education, working in multidisciplinary teams, perform analysis, evaluation, design, production, validation and knowledge transfer at large scale using a Cloud Computing platform. Allowing teachers and students to have all the information required to ensure a homologated nationally knowledge of topics such as mathematics, statistics, chemistry, history, ethics, civism, etc. This work will start with a pilot test in Spanish and initially in two regional dialects Otomí and Náhuatl. Otomí has more than 285,000 speaking indigenes in Queretaro and Mexico´s central region. Náhuatl is number one indigenous dialect spoken in Mexico with more than 1,550,000 indigenes. The phase one of the project takes into account negotiations with indigenous tribes from different regions, and the Information and Communication technologies to deliver the knowledge to the indigenous schools in their native dialect. The methodology includes the following main milestones: Identification of the indigenous areas where Otomí and Náhuatl are the spoken dialects, research with the SEP the location of actual indigenous schools, analysis and inventory or current schools conditions, negotiation with tribe chiefs, analysis of the technological communication requirements to reach the indigenous communities, identification and inventory of local teachers technology knowledge, selection of a pilot topic, analysis of actual student competence with traditional education system, identification of local translators, design of the e-learning platform, design of the multimedia resources and storage strategy for “Cloud Computing”, translation of the topic to both dialects, Indigenous teachers training, pilot test, course release, project follow up, analysis of student requirements for the new technological platform, definition of a new and improved proposal with greater reach in topics and regions. Importance of phase one of the project is multiple, it includes the proposal of a working technological scheme, focusing in the cultural impact in Mexico so that indigenous tribes can improve their knowledge about new forms of crop improvement, home storage technologies, proven home remedies for common diseases, ways of preparing foods containing major nutrients, disclose strengths and weaknesses of each region, communicating through cloud computing platforms offering regional products and opening communication spaces for inter-indigenous cultural exchange.
Keywords: Mexicans indigenous tribes, education, knowledge transfer, cloud computing, Otomí, Náhuatl, language.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 891422 MHD Falkner-Skan Boundary Layer Flow with Internal Heat Generation or Absorption
Authors: G.Ashwini, A.T.Eswara
Abstract:
This paper examines the forced convection flow of incompressible, electrically conducting viscous fluid past a sharp wedge in the presence of heat generation or absorption with an applied magnetic field. The system of partial differential equations governing Falkner - Skan wedge flow and heat transfer is first transformed into a system of ordinary differential equations using similarity transformations which is later solved using an implicit finite - difference scheme, along with quasilinearization technique. Numerical computations are performed for air (Pr = 0.7) and displayed graphically to illustrate the influence of pertinent physical parameters on local skin friction and heat transfer coefficients and, also on, velocity and temperature fields. It is observed that the magnetic field increases both the coefficients of skin friction and heat transfer. The effect of heat generation or absorption is found to be very significant on heat transfer, but its effect on the skin friction is negligible. Indeed, the occurrence of overshoot is noticed in the temperature profiles during heat generation process, causing the reversal in the direction of heat transfer.Keywords: Heat generation / absorption, MHD Falkner- Skan flow, skin friction and heat transfer
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2236