Search results for: growth rate of GDP
791 Educational Data Mining: The Case of Department of Mathematics and Computing in the Period 2009-2018
Authors: M. Sitoe, O. Zacarias
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University education is influenced by several factors that range from the adoption of strategies to strengthen the whole process to the academic performance improvement of the students themselves. This work uses data mining techniques to develop a predictive model to identify students with a tendency to evasion and retention. To this end, a database of real students’ data from the Department of University Admission (DAU) and the Department of Mathematics and Informatics (DMI) was used. The data comprised 388 undergraduate students admitted in the years 2009 to 2014. The Weka tool was used for model building, using three different techniques, namely: K-nearest neighbor, random forest, and logistic regression. To allow for training on multiple train-test splits, a cross-validation approach was employed with a varying number of folds. To reduce bias variance and improve the performance of the models, ensemble methods of Bagging and Stacking were used. After comparing the results obtained by the three classifiers, Logistic Regression using Bagging with seven folds obtained the best performance, showing results above 90% in all evaluated metrics: accuracy, rate of true positives, and precision. Retention is the most common tendency.
Keywords: Evasion and retention, cross validation, bagging, stacking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 118790 Effects of a Methanol Fraction of the Leaves of Leonotis leonurus on the Blood Pressure and Heart Rate of Normotensive Male Wistar Rats
Authors: K. Obikeze, P. Mugabo, I. Green, D. Dietrich, A. Burger
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Leonotisleonurus a shrub indigenous to Southern Africa is widely used in traditional medicine to treat a variety of conditions ranging from skin diseases and cough to epileptic fits and ‘heart problems’. Studies on the aqueous extract of the leaves have indicated cycloxegenase enzyme inhibitory activity and an antihypertensive effect. Five methanol leaf extract fractions (MLEa - MLEe) of L. leonurus were tested on anaesthetized normotensive male Wistar rats (AWR) and isolated perfused working rat hearts (IWH). Fraction MLEc (0.01mg/kg – 0.05mg/kg) induced significant increases in BP and HR in AWR and positive chronotropic and inotropic effects in IWH (1.0mg/ml – 5.0mg/ml). Pre-administration of atenolol (2.0mg/kg) and prazosin (60μg/kg) significantly inhibited MLEc effect on HR and MAP respectively in vivo, while atenolol (7.0mg/ml) pre-perfusion significantly inhibited MLEc effect in vitro. The hypertensive effect of MLEc is probably via β1agonism. Results also indicate the presence of multiple cardioactive compounds in L. leonurus.
Keywords: Cardiovascular effect, in vitro, in vivo, isolated perfused working heart, Leonotis leonurus, rat.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2091789 Strategic Thinking to Change Behavior and Improve Sanitation in Jodipan and Kesatrian, Malang, East Java, Indonesia
Authors: Prasanti Widyasih Sarli, Prayatni Soewondo
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Greater access to sanitation in developing countries is urgent. However even though sanitation is crucial, overall budget for sanitation is limited. With this budget limitation, it is important to (1) allocate resources strategically to maximize impact and (2) take into account communal agency to potentially be a source for sanitation improvements. The Jodipan and Kesatrian Project in Malang, Indonesia is an interesting alternative for solving the sanitation problem in which resources were allocated strategically and communal agency was also observed. Although the projects initial goal was only to improve visually the situation in the slums, it became a new tourist destination, and the economic benefit that came with it had an effect also on the change of behavior of the residents and the government towards sanitation. It also grew from only including the Kesatrian Village to expanding to the Jodipan Village in the course of less than a year. To investigate the success of this project, in this paper a descriptive model will be used and data will be drawn from intensive interviews with the initiators of the project, residents affected by the project and government officials. In this research it is argued that three points mark the success of the project: (1) the strategic initial impact due to choice of location, (2) the influx of tourists that triggered behavioral change among residents and, (3) the direct economic impact which ensured its sustainability and growth by gaining government officials support and attention for more public spending in the area for slum development and sanitation improvement.Keywords: Behavior change, sanitation, slum, strategic thinking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 996788 Application of Metakaolin from Northeast of Thailand Used as Binder in Casting Process of Rice Polishing Cylinder
Authors: T. Boonkang, C. Santhaweesuk, N. Pianthong, P. Neeramon, A. Phimhlo, S. Bangphan
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The objective of this research was to apply metakaolin from northeast of Thailand as a binder in the casting process of rice polishing cylinder in replacement of the imported calcined magnesite cement and to reduce the production cost of the cylinder. Metakaolin was obtained from three different regions (Udon Thani, Nakhon Phanom, and Ubon Ratchathani). The design of experiment analysis using the MINITAB Release 14 based on the compressive strength and tensile strength testing was conducted. According to the analysis results, it was found that the optimal proportions were calcined magnesite cement: metakaolin from Udon Thani, Nakhon Phanom and Ubon Ratchathani equal to 63:37, 71:29, and 100:0, respectively. When used this formula to cast the cylinder and test the rice milling, it was found that the average broken rice percent was 32.52 and 38.29 for the cylinder contained the metakaolin from Udon Thani and Nakhon Phanom, respectively, which implied that the cylinder which contained the metakaolin from Udon Thani has higher efficiency than the cylinder which contained the metakaolin from Nakhon Phanom at 0.05 level of statistical significance. Whereas, the average wear rate of cylinder from both resources were 7.27 and 6.53 g/h, respectively.Keywords: Binder, casting, metakaolin, rice polishing cylinder.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1154787 Discovery of Human HMG-Coa Reductase Inhibitors Using Structure-Based Pharmacophore Modeling Combined with Molecular Dynamics Simulation Methodologies
Authors: Minky Son, Chanin Park, Ayoung Baek, Shalini John, Keun Woo Lee
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3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) catalyzes the conversion of HMG-CoA to mevalonate using NADPH and the enzyme is involved in rate-controlling step of mevalonate. Inhibition of HMGR is considered as effective way to lower cholesterol levels so it is drug target to treat hypercholesterolemia, major risk factor of cardiovascular disease. To discover novel HMGR inhibitor, we performed structure-based pharmacophore modeling combined with molecular dynamics (MD) simulation. Four HMGR inhibitors were used for MD simulation and representative structure of each simulation were selected by clustering analysis. Four structure-based pharmacophore models were generated using the representative structure. The generated models were validated used in virtual screening to find novel scaffolds for inhibiting HMGR. The screened compounds were filtered by applying drug-like properties and used in molecular docking. Finally, four hit compounds were obtained and these complexes were refined using energy minimization. These compounds might be potential leads to design novel HMGR inhibitor.
Keywords: Anti-hypercholesterolemia drug, HMGR inhibitor, Molecular dynamics simulation, Structure-based pharmacophore modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1947786 Effect of Bentonite on the Rheological Behavior of Cement Grout in Presence of Superplasticizer
Authors: K. Benyounes, A. Benmounah
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Cement-based grouts has been used successfully to repair cracks in many concrete structures such as bridges, tunnels, buildings and to consolidate soils or rock foundations. In the present study the rheological characterization of cement grout with water/binder ratio (W/B) is fixed at 0.5. The effect of the replacement of cement by bentonite (2 to 10% wt) in presence of superplasticizer (0.5% wt) was investigated. Several rheological tests were carried out by using controlled-stress rheometer equipped with vane geometry in temperature of 20°C. To highlight the influence of bentonite and superplasticizer on the rheological behavior of grout cement, various flow tests in a range of shear rate from 0 to 200 s-1 were observed. Cement grout showed a non-Newtonian viscosity behavior at all concentrations of bentonite. Three parameter model Herschel- Bulkley was chosen for fitting of experimental data. Based on the values of correlation coefficients of the estimated parameters, The Herschel-Bulkley law model well described the rheological behavior of the grouts. Test results showed that the dosage of bentonite increases the viscosity and yield stress of the system and introduces more thixotropy. While the addition of both bentonite and superplasticizer with cement grout improve significantly the fluidity and reduced the yield stress due to the action of dispersion of SP.
Keywords: Cement grout, bentonite, superplasticizer, viscosity, yield stress.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3563785 Present State of Local Public Transportation Service in Local Municipalities of Japan and Its Effects on Population
Authors: Akiko Kondo, Akio Kondo
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We are facing regional problems to low birth rate and longevity in Japan. Under this situation, there are some local municipalities which lose their vitality. The aims of this study are to clarify the present state of local public transportation services in local municipalities and relation between local public transportation services and population quantitatively. We conducted a questionnaire survey concerning regional agenda in all local municipalities in Japan. We obtained responses concerning the present state of convenience in use of public transportation and local public transportation services. Based on the data gathered from the survey, it is apparent that we should some sort of measures concerning public transportation services. Convenience in use of public transportation becomes an object of public concern in many rural regions. It is also clarified that some local municipalities introduce a demand bus for the purpose of promotion of administrative and financial efficiency. They also introduce a demand taxi in order to secure transportation to weak people in transportation and eliminate of blank area related to public transportation services. In addition, we construct a population model which includes explanatory variables of present states of local public transportation services. From this result, we can clarify the relation between public transportation services and population quantitatively.
Keywords: Public transportation, local municipality, regional analysis, regional issue.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1894784 Study of Sickle Cell Syndromes in the Population of the Region of Batna
Authors: K .Belhadi, H. Bousselsela, M. Yahia, A. Zidani, S. Benbia
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Sickle cell anemia is a recessive genetic disease caused by the presence in the red blood cell, of abnormal hemoglobin called hemoglobin S. It results from the replacement in the beta chain of the acid glutamic acid by valin at position 6. Topics may be homozygous (SS) or heterozygous (AS) most often asymptomatic. Other mutations result in compound heterozygous: - Synthesis of hemoglobin C mutation in the sixth leucin codon (heterozygous SC); - ß-thalassemia (heterozygous S-ß thalassemia). SS homozygous, heterozygous SC and S- ß -thalassemia are grouped under the major sickle cell syndromes. To make a laboratory diagnosis of hemoglobinopathies in a portion of the population in region of Batna, our study was conducted on 115 patients with suspected sickle cell anemia, all cases have benefited from hematological tests as blood count (count RBC, calculated erythrocyte indices, MCV and MCHC, measuring the hemoglobin concentration) and a biochemical test in this case electrophoresis CAPILLARYS HEMOGLOBIN (E). The results showed: 27 cases of sickle cell anemia were found on 115 suspected cases, 73,03% homozygous sickle cell disease and 59,25% sickle cell trait. Finally, the double heterozygous S/C, represent the incidence rate of 3, 70%.Keywords: Hemoglobin, sickle cell syndromes, laboratory diagnosis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1543783 Advanced Micromanufacturing for Ultra Precision Part by Soft Lithography and Nano Powder Injection Molding
Authors: Andy Tirta, Yus Prasetyo, Eung-Ryul. Baek, Chul-Jin. Choi , Hye-Moon. Lee
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Recently, the advanced technologies that offer high precision product, relative easy, economical process and also rapid production are needed to realize the high demand of ultra precision micro part. In our research, micromanufacturing based on soft lithography and nanopowder injection molding was investigated. The silicone metal pattern with ultra thick and high aspect ratio succeeds to fabricate Polydimethylsiloxane (PDMS) micro mold. The process followed by nanopowder injection molding (PIM) by a simple vacuum hot press. The 17-4ph nanopowder with diameter of 100 nm, succeed to be injected and it forms green sample microbearing with thickness, microchannel and aspect ratio is 700μm, 60μm and 12, respectively. Sintering process was done in 1200 C for 2 hours and heating rate 0.83oC/min. Since low powder load (45% PL) was applied to achieve green sample fabrication, ~15% shrinkage happen in the 86% relative density. Several improvements should be done to produce high accuracy and full density sintered part.Keywords: Micromanufacturing, Nano PIM, PDMS micro mould.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2061782 Orchestra/Percussion Classification Algorithm for United Speech Audio Coding System
Authors: Yueming Wang, Rendong Ying, Sumxin Jiang, Peilin Liu
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Unified Speech Audio Coding (USAC), the latest MPEG standardization for unified speech and audio coding, uses a speech/audio classification algorithm to distinguish speech and audio segments of the input signal. The quality of the recovered audio can be increased by well-designed orchestra/percussion classification and subsequent processing. However, owing to the shortcoming of the system, introducing an orchestra/percussion classification and modifying subsequent processing can enormously increase the quality of the recovered audio. This paper proposes an orchestra/percussion classification algorithm for the USAC system which only extracts 3 scales of Mel-Frequency Cepstral Coefficients (MFCCs) rather than traditional 13 scales of MFCCs and use Iterative Dichotomiser 3 (ID3) Decision Tree rather than other complex learning method, thus the proposed algorithm has lower computing complexity than most existing algorithms. Considering that frequent changing of attributes may lead to quality loss of the recovered audio signal, this paper also design a modified subsequent process to help the whole classification system reach an accurate rate as high as 97% which is comparable to classical 99%.
Keywords: ID3 Decision Tree, MFCC, Orchestra/Percussion Classification, USAC
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1672781 Stereotypical Motor Movement Recognition Using Microsoft Kinect with Artificial Neural Network
Authors: M. Jazouli, S. Elhoufi, A. Majda, A. Zarghili, R. Aalouane
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Autism spectrum disorder is a complex developmental disability. It is defined by a certain set of behaviors. Persons with Autism Spectrum Disorders (ASD) frequently engage in stereotyped and repetitive motor movements. The objective of this article is to propose a method to automatically detect this unusual behavior. Our study provides a clinical tool which facilitates for doctors the diagnosis of ASD. We focus on automatic identification of five repetitive gestures among autistic children in real time: body rocking, hand flapping, fingers flapping, hand on the face and hands behind back. In this paper, we present a gesture recognition system for children with autism, which consists of three modules: model-based movement tracking, feature extraction, and gesture recognition using artificial neural network (ANN). The first one uses the Microsoft Kinect sensor, the second one chooses points of interest from the 3D skeleton to characterize the gestures, and the last one proposes a neural connectionist model to perform the supervised classification of data. The experimental results show that our system can achieve above 93.3% recognition rate.
Keywords: ASD, stereotypical motor movements, repetitive gesture, kinect, artificial neural network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1904780 Fast Approximate Bayesian Contextual Cold Start Learning (FAB-COST)
Authors: Jack R. McKenzie, Peter A. Appleby, Thomas House, Neil Walton
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Cold-start is a notoriously difficult problem which can occur in recommendation systems, and arises when there is insufficient information to draw inferences for users or items. To address this challenge, a contextual bandit algorithm – the Fast Approximate Bayesian Contextual Cold Start Learning algorithm (FAB-COST) – is proposed, which is designed to provide improved accuracy compared to the traditionally used Laplace approximation in the logistic contextual bandit, while controlling both algorithmic complexity and computational cost. To this end, FAB-COST uses a combination of two moment projection variational methods: Expectation Propagation (EP), which performs well at the cold start, but becomes slow as the amount of data increases; and Assumed Density Filtering (ADF), which has slower growth of computational cost with data size but requires more data to obtain an acceptable level of accuracy. By switching from EP to ADF when the dataset becomes large, it is able to exploit their complementary strengths. The empirical justification for FAB-COST is presented, and systematically compared to other approaches on simulated data. In a benchmark against the Laplace approximation on real data consisting of over 670, 000 impressions from autotrader.co.uk, FAB-COST demonstrates at one point increase of over 16% in user clicks. On the basis of these results, it is argued that FAB-COST is likely to be an attractive approach to cold-start recommendation systems in a variety of contexts.Keywords: Cold-start, expectation propagation, multi-armed bandits, Thompson sampling, variational inference.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 550779 The Relationship between Personality Characteristics and Driving Behavior
Authors: Bahram Esmaeili, Hamid Reza Imani Far, Hossein Hosseini, Mohammad Sharifi
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The present study investigated the relationship between personality characteristics of drivers and the number and amount of fines they have in a year .This study was carried out on 120 male taxi drivers that worked at least seven hours in a day in Lamerd - a city in the south of IRAN. Subjects were chosen voluntarily among those available. Predictive variables were the NEO –five great personality factors (1. conscientiousness 2. Openness to Experience 3.Neuroticism4 .Extraversion 5.Agreeableness ) thecriterion variables were the number and amount of fines the drivers have had the last three years. the result of regression analysis showed that conscientiousness factor was able to negatively predict the number and amount of financial fines the drivers had during the last three years. The openness factor positively predicted the number of fines they had in last 3 years and the amount of financial fines during the last year. The extraversion factor both meaningfully and positively could predict only the amount of financial fines they had during the last year. Increasing age was associated with decreasing driving offenses as well as financial loss.The findings can be useful in recognizing the high-risk drivers and leading them to counseling centers .They can also be used to inform the drivers about their personality and it’s relation with their accident rate. Such criteria would be of great importance in employing drivers in different places such as companies, offices etc…Keywords: drivers, financial fines, neo five-factor personality
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2464778 The Sustainable Strategies Research for Renewal of “Villages in City”: A Case Study of Liuzhou in Southwestern China
Authors: Kai Zhang
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Transformation under the reconfiguration of urban-rural relation in Liuzhou city has never been as radical and visible as it has been since the tremendous turn of the last century in China. Huanjiang village is located in Linhuashan Scenic Area in the middle east of Liuzhou city, with spectacular landscape and traditional features. Nowadays Huanjiang village has become a so-called "village in city", which is considered full of great potential for development because of the economic value of regional advantages during the urban sprawl. Communities of village found it difficult to acclimatize with the dramatic changes, which later led to numerous problems including ecological damage, unemployment of landless farmers and loss of traditional culture. Government has started up a series of renewal planings to resolve the problems, which are based on advanced technology and conform to sustainable and integrated strategies of city planning considering the original context and historical culture, superseding the traditional arrangements based on the guide of extensive economic growth. This paper aims to elaborate the context of Liuzhou city and Huanjiang village offered to both the traditional and sustainable planning approaches, in order to understand challenges and solutions of the rebuilding process. Through the analysis of the place relevant to architecture, society and culture, it will establish the corresponding systematic strategies. Considering the local features, it concludes with a comprehensive perspective on organic renewal in the case of Huanjiang village.
Keywords: China, Liuzhou, sustainable strategy, urban renewal, village in city.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 791777 Environmental Efficiency of Electric Power Industry of the United States: A Data Envelopment Analysis Approach
Authors: Alexander Y. Vaninsky
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Importance of environmental efficiency of electric power industry stems from high demand for energy combined with global warming concerns. It is especially essential for the world largest economies like that of the United States. The paper introduces a Data Envelopment Analysis (DEA) model of environmental efficiency using indicators of fossil fuels utilization, emissions rate, and electric power losses. Using DEA is advantageous in this situation over other approaches due to its nonparametric nature. The paper analyzes data for the period of 1990 - 2006 by comparing actual yearly levels in each dimension with the best values of partial indicators for the period. As positive factors of efficiency, tendency to the decline in emissions rates starting 2000, and in electric power losses starting 2004 may be mentioned together with increasing trend of fuel utilization starting 1999. As a result, dynamics of environmental efficiency is positive starting 2002. The main concern is the decline in fossil fuels utilization in 2006. This negative change should be reversed to comply with ecological and economic requirements.
Keywords: Environmental efficiency, electric power industry, DEA, United States.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1904776 Drivers of Land Degradation in Trays Ecosystem as Modulated under a Changing Climate: Case Study of Côte d'Ivoire
Authors: Kadio Valere R. Angaman, Birahim Bouna Niang
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Land degradation is a serious problem in developing countries including Cote d’Ivoire, which has its economy focused on agriculture. It occurs in all kinds of ecosystems over the world. However, the drivers of land degradation vary from one region to another, and from one ecosystem to another. Thus, identifying these drivers is an essential prerequisite to develop and implement appropriate policies to reverse the trend of land degradation in the country, especially in the trays ecosystem. Using the binary logistic model with primary data obtained through 780 farmers surveyed, we analyze and identify the drivers of land degradation in the trays ecosystem. The descriptive statistics show that 52% of farmers interviewed have stated facing land degradation in their farmland. This high rate shows the extent of land degradation in this ecosystem. Also, the results obtained from the binary logit regression reveal that land degradation is significantly influenced by a set of variables such as sex, education, slope, erosion, pesticide, agricultural activity, deforestation, and temperature. The drivers identified are mostly local, as a result, the government must implement some policies and strategies that facilitate and incentive the adoption of sustainable land management practices by farmers to reverse the negative trend of land degradation.
Keywords: Drivers, land degradation, trays ecosystem, sustainable land management.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 417775 A Study on the Leadership Behavior, Safety Culture, and Safety Performance of the Healthcare Industry
Authors: Cheng-Chia Yang , Yi-Shun Wang , Sue-Ting Chang, Suh-Er Guo, Mei-Fen Huang
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Object: Review recent publications of patient safety culture to investigate the relationship between leadership behavior, safety culture, and safety performance in the healthcare industry. Method: This study is a cross-sectional study, 350 questionnaires were mailed to hospital workers with 195 valid responses obtained, and a 55.7% valid response rate. Confirmatory factor analysis (CFA) was carried out to test the factor structure and determine if the composite reliability was significant with a factor loading of >0.5, resulting in an acceptable model fit. Results: Through the analysis of One-way ANOVA, the results showed that physicians significantly have more negative patient safety culture perceptions and safety performance perceptions than non- physicians. Conclusions: The path analysis results show that leadership behavior affects safety culture and safety performance in the health care industry. Safety performance was affected and improved with contingency leadership and a positive patient safety organization culture. The study suggests improving safety performance by providing a well-managed system that includes: consideration of leadership, hospital worker training courses, and a solid safety reporting system.Keywords: Leadership Behavior, Patient Safety, Safety Culture, Safety Performance
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3994774 CFD Modeling of Mixing Enhancement in a Pitted Micromixer by High Frequency Ultrasound Waves
Authors: Faezeh Mohammadi, Ebrahim Ebrahimi, Neda Azimi
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Use of ultrasound waves is one of the techniques for increasing the mixing and mass transfer in the microdevices. Ultrasound propagation into liquid medium leads to stimulation of the fluid, creates turbulence and so increases the mixing performance. In this study, CFD modeling of two-phase flow in a pitted micromixer equipped with a piezoelectric with frequency of 1.7 MHz has been studied. CFD modeling of micromixer at different velocity of fluid flow in the absence of ultrasound waves and with ultrasound application has been performed. The hydrodynamic of fluid flow and mixing efficiency for using ultrasound has been compared with the layout of no ultrasound application. The result of CFD modeling shows well agreements with the experimental results. The results showed that the flow pattern inside the micromixer in the absence of ultrasound waves is parallel, while when ultrasound has been applied, it is not parallel. In fact, propagation of ultrasound energy into the fluid flow in the studied micromixer changed the hydrodynamic and the forms of the flow pattern and caused to mixing enhancement. In general, from the CFD modeling results, it can be concluded that the applying ultrasound energy into the liquid medium causes an increase in the turbulences and mixing and consequently, improves the mass transfer rate within the micromixer.
Keywords: CFD modeling, ultrasound, mixing, mass transfer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 754773 Laminar Free Convection of Nanofluid Flow in Horizontal Porous Annulus
Authors: Manal H. Saleh
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A numerical study has been carried out to investigate the heat transfer by natural convection of nanofluid taking Cu as nanoparticles and the water as based fluid in a three dimensional annulus enclosure filled with porous media (silica sand) between two horizontal concentric cylinders with 12 annular fins of 2.4mm thickness attached to the inner cylinder under steady state conditions. The governing equations which used are continuity, momentum and energy equations under an assumptions used Darcy law and Boussinesq-s approximation which are transformed to dimensionless equations. The finite difference approach is used to obtain all the computational results using the MATLAB-7. The parameters affected on the system are modified Rayleigh number (10 ≤Ra*≤ 1000), fin length Hf (3, 7 and 11mm), radius ratio Rr (0.293, 0.365 and 0.435) and the volume fraction(0 ≤ ¤ò ≤ 0 .35). It was found that the average Nusselt number depends on (Ra*, Hf, Rr and φ). The results show that, increasing of fin length decreases the heat transfer rate and for low values of Ra*, decreasing Rr cause to decrease Nu while for Ra* greater than 100, decreasing Rr cause to increase Nu and adding Cu nanoparticles with 0.35 volume fraction cause 27.9% enhancement in heat transfer. A correlation for Nu in terms of Ra*, Hf and φ, has been developed for inner hot cylinder.Keywords: Annular fins, laminar free convection, nanofluid, porous media, three dimensions horizontal annulus.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2488772 A Computational Stochastic Modeling Formalism for Biological Networks
Authors: Werner Sandmann, Verena Wolf
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Stochastic models of biological networks are well established in systems biology, where the computational treatment of such models is often focused on the solution of the so-called chemical master equation via stochastic simulation algorithms. In contrast to this, the development of storage-efficient model representations that are directly suitable for computer implementation has received significantly less attention. Instead, a model is usually described in terms of a stochastic process or a "higher-level paradigm" with graphical representation such as e.g. a stochastic Petri net. A serious problem then arises due to the exponential growth of the model-s state space which is in fact a main reason for the popularity of stochastic simulation since simulation suffers less from the state space explosion than non-simulative numerical solution techniques. In this paper we present transition class models for the representation of biological network models, a compact mathematical formalism that circumvents state space explosion. Transition class models can also serve as an interface between different higher level modeling paradigms, stochastic processes and the implementation coded in a programming language. Besides, the compact model representation provides the opportunity to apply non-simulative solution techniques thereby preserving the possible use of stochastic simulation. Illustrative examples of transition class representations are given for an enzyme-catalyzed substrate conversion and a part of the bacteriophage λ lysis/lysogeny pathway.
Keywords: Computational Modeling, Biological Networks, Stochastic Models, Markov Chains, Transition Class Models.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1578771 Wind Power Assessment for Turkey and Evaluation by APLUS Code
Authors: Ibrahim H. Kilic, A. B. Tugrul
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Energy is a fundamental component in economic development and energy consumption is an index of prosperity and the standard of living. The consumption of energy per capita has increased significantly over the last decades, as the standard of living has improved. Turkey’s geographical location has several advantages for extensive use of wind power. Among the renewable sources, Turkey has very high wind energy potential. Information such as installation capacity of wind power plants in installation, under construction and license stages in the country are reported in detail. Some suggestions are presented in order to increase the wind power installation capacity of Turkey. Turkey’s economic and social development has led to a massive increase in demand for electricity over the last decades. Since the Turkey has no major oil or gas reserves, it is highly dependent on energy imports and is exposed to energy insecurity in the future. But Turkey does have huge potential for renewable energy utilization. There has been a huge growth in the construction of wind power plants and small hydropower plants in recent years. To meet the growing energy demand, the Turkish Government has adopted incentives for investments in renewable energy production. Wind energy investments evaluated the impact of feed-in tariffs (FIT) based on three scenarios that are optimistic, realistic and pessimistic with APLUS software that is developed for rational evaluation for energy market. Results of the three scenarios are evaluated in the view of electricity market for Turkey.
Keywords: APLUS, energy policy, renewable energy, wind power, Turkey.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1027770 A New Approach for Predicting and Optimizing Weld Bead Geometry in GMAW
Authors: Farhad Kolahan, Mehdi Heidari
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Gas Metal Arc Welding (GMAW) processes is an important joining process widely used in metal fabrication industries. This paper addresses modeling and optimization of this technique using a set of experimental data and regression analysis. The set of experimental data has been used to assess the influence of GMAW process parameters in weld bead geometry. The process variables considered here include voltage (V); wire feed rate (F); torch Angle (A); welding speed (S) and nozzle-to-plate distance (D). The process output characteristics include weld bead height, width and penetration. The Taguchi method and regression modeling are used in order to establish the relationships between input and output parameters. The adequacy of the model is evaluated using analysis of variance (ANOVA) technique. In the next stage, the proposed model is embedded into a Simulated Annealing (SA) algorithm to optimize the GMAW process parameters. The objective is to determine a suitable set of process parameters that can produce desired bead geometry, considering the ranges of the process parameters. Computational results prove the effectiveness of the proposed model and optimization procedure.Keywords: Weld Bead Geometry, GMAW welding, Processparameters Optimization, Modeling, SA algorithm
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2186769 Cross-Border Shopping Motivation, Behaviours and Ethnocentrism of Malaysian in Hatyai, Thailand
Authors: Wanwisa Kuncharin, Badaruddin Mohamed
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There have been few studies of cross-border shopping. However, many have focused on macroeconomic effects rather than on discovering the motivation and behaviour of cross-border shoppers who purchase abroad. Hatyai, Thailand is located about 30 km from the Malaysian border. The statistics reports that each year more than 400,000 Malaysian visitors visited Hatyai. The aims of this study are fourfold: (1) to investigate factors motivating cross-border shoppers to shop in Hatyai, Thailand; (2) to examine the relationship between ethnicity and shopper ethnocentrism; (3) to discover the impact of shopper ethnocentrism on foreign product judgment; and (4) to explore the impact of shopper ethnocentrism on the willingness to buy foreign products. The results reveal that the three most popular consumption items were food and beverages, clothing, and grocery products. Factor analysis shows that the three key reasons for choosing Hatyai as the cross-border shopping destination included product and store, close distance, and low exchange rate. Moreover, there were significant differences in ethnocentrism by three ethnic groups. Shopper ethnocentrism had a significant negative correlation with foreign product judgment, while shopper ethnocentrism was not significantly correlated with willingness to buy foreign products.
Keywords: Cross-border shopping behaviours, Malaysian shoppers, Ethnocentrism, Hatyai, Thailand.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3867768 A Novel Approach to Iris Localization for Iris Biometric Processing
Authors: Somnath Dey, Debasis Samanta
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Iris-based biometric system is gaining its importance in several applications. However, processing of iris biometric is a challenging and time consuming task. Detection of iris part in an eye image poses a number of challenges such as, inferior image quality, occlusion of eyelids and eyelashes etc. Due to these problems it is not possible to achieve 100% accuracy rate in any iris-based biometric authentication systems. Further, iris detection is a computationally intensive task in the overall iris biometric processing. In this paper, we address these two problems and propose a technique to localize iris part efficiently and accurately. We propose scaling and color level transform followed by thresholding, finding pupil boundary points for pupil boundary detection and dilation, thresholding, vertical edge detection and removal of unnecessary edges present in the eye images for iris boundary detection. Scaling reduces the search space significantly and intensity level transform is helpful for image thresholding. Experimental results show that our approach is comparable with the existing approaches. Following our approach it is possible to detect iris part with 95-99% accuracy as substantiated by our experiments on CASIA Ver-3.0, ICE 2005, UBIRIS, Bath and MMU iris image databases.
Keywords: Iris recognition, iris localization, biometrics, image processing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3189767 Optimization of Surface Roughness in Turning Process Utilizing Live Tooling via Taguchi Methodology
Authors: Weinian Wang, Joseph C. Chen
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The objective of this research is to optimize the process of cutting cylindrical workpieces utilizing live tooling on a HAAS ST-20 lathe. Surface roughness (Ra) has been investigated as the indicator of quality characteristics for machining process. Aluminum alloy was used to conduct experiments due to its wide range usages in engineering structures and components where light weight or corrosion resistance is required. In this study, Taguchi methodology is utilized to determine the effects that each of the parameters has on surface roughness (Ra). A total of 18 experiments of each process were designed according to Taguchi’s L9 orthogonal array (OA) with four control factors at three levels of each and signal-to-noise ratios (S/N) were computed with Smaller the better equation for minimizing the system. The optimal parameters identified for the surface roughness of the turning operation utilizing live tooling were a feed rate of 3 inches/min(A3); a spindle speed of 1300 rpm(B3); a 2-flute titanium nitrite coated 3/8” endmill (C1); and a depth of cut of 0.025 inches (D2). The mean surface roughness of the confirmation runs in turning operation was 8.22 micro inches. The final results demonstrate that Taguchi methodology is a sufficient way of process improvement in turning process on surface roughness.
Keywords: Live tooling, surface roughness, Taguchi Parameter Design, CNC turning operation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 803766 Image Transmission: A Case Study on Combined Scheme of LDPC-STBC in Asynchronous Cooperative MIMO Systems
Authors: Shan Ding, Lijia Zhang, Hongming Xu
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this paper presents a novel scheme which is capable of reducing the error rate and improves the transmission performance in the asynchronous cooperative MIMO systems. A case study of image transmission is applied to prove the efficient of scheme. The linear dispersion structure is employed to accommodate the cooperative wireless communication network in the dynamic topology of structure, as well as to achieve higher throughput than conventional space–time codes based on orthogonal designs. The LDPC encoder without girth-4 and the STBC encoder with guard intervals are respectively introduced. The experiment results show that the combined coder of LDPC-STBC with guard intervals can be the good error correcting coders and BER performance in the asynchronous cooperative communication. In the case study of image transmission, the results show that in the transmission process, the image quality which is obtained by applied combined scheme is much better than it which is not applied the scheme in the asynchronous cooperative MIMO systems.
Keywords: Cooperative MIMO, image transmission, lineardispersion codes, Low-Density Parity-Check (LDPC)
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1932765 Feasibility and Penetration of Electric Vehicles in Indian Power Grid
Authors: Kashyap L. Mokariya, Varsha A. Shah, Makarand M. Lokhande
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As the current status and growth of Indian automobile industry is remarkable, transportation sectors are the main concern in terms of energy security and climate change. Due to rising demand of fuel and its dependency on foreign countries that affects the GDP of nation, suggests that penetration of electrical vehicle will increase in near future. So in this context analysis is done if the 10 percent of conventional vehicles including cars, three wheelers and two wheelers becomes electrical vehicles in near future which is also a part of Nations Electric Mobility Mission Plan then the saving which improves the nation’s economy is analyzed in detail. Whether the Indian electricity grid is capable of taking this load with current generation and demand all over the country is also analyzed in detail. Current situation of Indian grid is analyzed and how the gap between generation and demand can be reduced is discussed in terms of increasing generation capacity and energy conservation measures. Electrical energy conservation measures in Industry and especially in rural areas have been analyzed to improve performance of Indian electricity grid in context of electrical vehicle penetration in near future. Author was a part of Vishvakarma yojna in which energy losses were measured in 255 villages of Gujarat and solutions were suggested to mitigate them and corresponding reports was submitted to the authorities of Gujarat government.
Keywords: Vehicle penetration, feasibility, Energy conservation, future grid, Energy security, Automatic pf controller.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4108764 Ellagic Acid Enhanced Apoptotic Radiosensitivity via G1 Cell Cycle Arrest and γ-H2AX Foci Formation in HeLa Cells in vitro
Authors: V. R. Ahire, A. Kumar, B. N. Pandey, K. P. Mishra, G. R. Kulkarni
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Radiation therapy is an effective vital strategy used globally in the treatment of cervical cancer. However, radiation efficacy principally depends on the radiosensitivity of the tumor, and not all patient exhibit significant response to irradiation. A radiosensitive tumor is easier to cure than a radioresistant tumor which later advances to local recurrence and metastasis. Herbal polyphenols are gaining attention for exhibiting radiosensitization through various signaling. Current work focuses to study the radiosensitization effect of ellagic acid (EA), on HeLa cells. EA intermediated radiosensitization of HeLa cells was due to the induction γ-H2AX foci formation, G1 phase cell cycle arrest, and loss of reproductive potential, growth inhibition, drop in the mitochondrial membrane potential and protein expression studies that eventually induced apoptosis. Irradiation of HeLa in presence of EA (10 μM) to doses of 2 and 4 Gy γ-radiation produced marked tumor cytotoxicity. EA also demonstrated radio-protective effect on normal cell, NIH3T3 and aided recovery from the radiation damage. Our results advocate EA to be an effective adjuvant for improving cancer radiotherapy as it displays striking tumor cytotoxicity and reduced normal cell damage instigated by irradiation.Keywords: Apoptotic radiosensitivity, ellagic acid, mitochondrial potential, cell-cycle arrest.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 875763 Empirical Evidence on Equity Valuation of Thai Firms
Authors: Somchai Supattarakul, Anya Khanthavit
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This study aims at providing empirical evidence on a comparison of two equity valuation models: (1) the dividend discount model (DDM) and (2) the residual income model (RIM), in estimating equity values of Thai firms during 1995-2004. Results suggest that DDM and RIM underestimate equity values of Thai firms and that RIM outperforms DDM in predicting cross-sectional stock prices. Results on regression of cross-sectional stock prices on the decomposed DDM and RIM equity values indicate that book value of equity provides the greatest incremental explanatory power, relative to other components in DDM and RIM terminal values, suggesting that book value distortions resulting from accounting procedures and choices are less severe than forecast and measurement errors in discount rates and growth rates. We also document that the incremental explanatory power of book value of equity during 1998-2004, representing the information environment under Thai Accounting Standards reformed after the 1997 economic crisis to conform to International Accounting Standards, is significantly greater than that during 1995-1996, representing the information environment under the pre-reformed Thai Accounting Standards. This implies that the book value distortions are less severe under the 1997 Reformed Thai Accounting Standards than the pre-reformed Thai Accounting Standards.Keywords: Dividend Discount Model, Equity Valuation Model, Residual Income Model, Thai Stock Market
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1889762 A Supervised Learning Data Mining Approach for Object Recognition and Classification in High Resolution Satellite Data
Authors: Mais Nijim, Rama Devi Chennuboyina, Waseem Al Aqqad
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Advances in spatial and spectral resolution of satellite images have led to tremendous growth in large image databases. The data we acquire through satellites, radars, and sensors consists of important geographical information that can be used for remote sensing applications such as region planning, disaster management. Spatial data classification and object recognition are important tasks for many applications. However, classifying objects and identifying them manually from images is a difficult task. Object recognition is often considered as a classification problem, this task can be performed using machine-learning techniques. Despite of many machine-learning algorithms, the classification is done using supervised classifiers such as Support Vector Machines (SVM) as the area of interest is known. We proposed a classification method, which considers neighboring pixels in a region for feature extraction and it evaluates classifications precisely according to neighboring classes for semantic interpretation of region of interest (ROI). A dataset has been created for training and testing purpose; we generated the attributes by considering pixel intensity values and mean values of reflectance. We demonstrated the benefits of using knowledge discovery and data-mining techniques, which can be on image data for accurate information extraction and classification from high spatial resolution remote sensing imagery.Keywords: Remote sensing, object recognition, classification, data mining, waterbody identification, feature extraction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2052