Search results for: discontinuous sound field
1511 Effect of Isfahan Refinery, Power Plant and Petrochemical on Borkhar District Soil
Authors: A. Gandomkar
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This study aimed to evaluate regional soil Borkhar of the metals Lead has been made. In this field study fires visits to the regions. The limit of this study located in the East refineries, petrochemical and power plant to 20 km was selected. The 41 soil samples from depths of 0 to 10 cm in area and were randomized. Soil samples were transported to the laboratory and by air was dry and passed through 2-mil thickness sieve. In the laboratory of physical and chemical characteristics and concentrations of total absorption was measured. The results showed that the amount of lead in soil in many parts of the range higher than the standard limit. Survey maps show that the lead spatial distribution of the region does not special pattern.Keywords: Soil Pollution, Heavy Metals, Borkhar District, Soil Sampling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11681510 The Study on the Relationship between Momentum Profits and Psychological Factors: Evidence from Taiwan
Authors: Chih-Hsiang Chang
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This study provides insight into the effects of investor sentiment, excess optimism, overconfidence, the disposition effect, and herding formation on momentum profits. This study contributes to the field by providing a further examination of the relationship between psychological factors and momentum profits. The empirical results show that there is no evidence of significant momentum profits in Taiwan’s stock market. Additionally, investor sentiment in Taiwan’s stock market significantly influences its momentum profits.Keywords: Momentum profits, psychological factors, herding formation, investor sentiment.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11741509 Thermal Technologies Applications for Soil Remediation
Authors: A. de Folly d’Auris, R. Bagatin, P. Filtri
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This paper discusses the importance of having a good initial characterization of soil samples when thermal desorption has to be applied to polluted soils for the removal of contaminants. Particular attention has to be devoted on the desorption kinetics of the samples to identify the gases evolved during the heating, and contaminant degradation pathways. In this study, two samples coming from different points of the same contaminated site were considered. The samples are much different from each other. Moreover, the presence of high initial quantity of heavy hydrocarbons strongly affected the performance of thermal desorption, resulting in formation of dangerous intermediates. Analytical techniques such TGA (Thermogravimetric Analysis), DSC (Differential Scanning Calorimetry) and GC-MS (Gas Chromatography-Mass) provided a good support to give correct indication for field application.
Keywords: Desorption kinetics, hydrocarbons, thermal desorption, thermogravimetric measurements.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17061508 On the Prediction of Transmembrane Helical Segments in Membrane Proteins
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The prediction of transmembrane helical segments (TMHs) in membrane proteins is an important field in the bioinformatics research. In this paper, a method based on discrete wavelet transform (DWT) has been developed to predict the number and location of TMHs in membrane proteins. PDB coded as 1F88 was chosen as an example to describe the prediction of the number and location of TMHs in membrane proteins by using this method. One group of test data sets that contain total 19 protein sequences was utilized to access the effect of this method. Compared with the prediction results of DAS, PRED-TMR2, SOSUI, HMMTOP2.0 and TMHMM2.0, the obtained results indicate that the presented method has higher prediction accuracy.Keywords: hydrophobicity, membrane protein, transmembranehelical segments, wavelet transform
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15821507 The Portuguese Press Portrait of “Environmental Refugees“
Authors: Inês Vieira
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The migration-environment nexus has gained increased interest from the social research field over the last years. While straightly connected to human security issues, this theme has pervaded through the media to the public sphere. Therefore, it is important to observe how did the discussions over environmentally induced migrations develop from the scientific basis to the media attention, passing through some political voices, and in which ways might these messages be interpreted within the broader public discourses. To achieve this purpose, the analysis of the press entries between 2004 and 2010 in three of the main Portuguese newspapers shall be presented, specially reflecting upon the events, protagonists, topics, geographical attributions and terms/expressions used to define those who migrate due to environmental degradation or disasters.
Keywords: Climate refugees, environmental refugees, environmentally induced migrations, Portuguese written press
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15681506 Effects of Asphalt Modification with Nanomaterials on Fresh and Stored Bitumen
Authors: Ahmed W. Oda, Ahmed El-Desouky, Hassan Mahdy, Osama M. Moussa
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Nanomaterials have many applications in the field of asphalt paving. Two locally produced nanomaterials were used in the asphalt binder modification. The nanomaterials used are Nanosilica (NS), and Nanoclay (NC). The virgin asphalt binder was characterized by the conventional tests. The bitumen was modified by 3%, 5% and 7% of NS and NC. The penetration index (PI), and the retaining penetration (RP) was calculated based on the results of the penetration and the softening point tests. The results show that the RP becomes 95.35% at 5% NS modified bitumen and reaches 97.56% when bitumen is modified with 3% NC. The results show significant improvement in the bitumen stiffness when modified by the two types of nanomaterials, either fresh or aged (stored).
Keywords: Bitumen, modified bitumen, aged, stored, nanomaterials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8191505 A Numerical Study on Rear-spoiler of Passenger Vehicle
Authors: Xu-xia Hu, Eric T. T. Wong
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The simulation of external aerodynamics is one of the most challenging and important automotive CFD applications. With the rapid developments of digital computers, CFD is used as a practical tool in modern fluid dynamics research. It integrates fluid mechanics disciplines, mathematics and computer science. In this study, two different types of simulations were made, one for the flow around a simplified high speed passenger car with a rear-spoiler and the other for the flow without a rear-spoiler. The standard k-ε model is selected to numerically simulate the external flow field of the simplified Camry model with or without a rear-spoiler. Through an analysis of the simulation results, a new rear spoiler is designed and it shows a mild reduction of the vehicle aerodynamics drag. This leads to less vehicle fuel consumption on the road.
Keywords: CFD, vehicle rear-spoiler design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 48981504 JREM: An Approach for Formalising Models in the Requirements Phase with JSON and NoSQL Databases
Authors: Aitana Alonso-Nogueira, Helia Estévez-Fernández, Isaías García
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This paper presents an approach to reduce some of its current flaws in the requirements phase inside the software development process. It takes the software requirements of an application, makes a conceptual modeling about it and formalizes it within JSON documents. This formal model is lodged in a NoSQL database which is document-oriented, that is, MongoDB, because of its advantages in flexibility and efficiency. In addition, this paper underlines the contributions of the detailed approach and shows some applications and benefits for the future work in the field of automatic code generation using model-driven engineering tools.
Keywords: Conceptual modeling, JSON, NoSQL databases, requirements engineering, software development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10821503 Creating or Destroying Objects Plan in the Graphplan Framework
Authors: Wen-xiang Gu, Zeng-yu Cai, Xin-mei Zhang, Gui-dong Jiang
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At present, intelligent planning in the Graphplan framework is a focus of artificial intelligence. While the Creating or Destroying Objects Planning (CDOP) is one unsolved problem of this field, one of the difficulties, too. In this paper, we study this planning problem and bring forward the idea of transforming objects to propositions, based on which we offer an algorithm, Creating or Destroying Objects in the Graphplan framework (CDOGP). Compared to Graphplan, the new algorithm can solve not only the entire problems that Graphplan do, but also a part of CDOP. It is for the first time that we introduce the idea of object-proposition, and we emphasize the discussion on the representations of creating or destroying objects operator and an algorithm in the Graphplan framework. In addition, we analyze the complexity of this algorithm.
Keywords: Graphplan, object_proposition, Creating or destroying objects, CDOGP.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12401502 A Compact Wearable Slot Antenna for LTE and WLAN Applications
Authors: Haider K. Raad
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In this paper, a compact wide-band, ultra-thin and flexible slot antenna intended for wearable applications is presented. The presented antenna is designed to provide Wireless Local Area Network (WLAN) and Long Term Evolution (LTE) connectivity. The presented design exhibits a relatively wide bandwidth (1600-3500 MHz below -6 dB impedance bandwidth limit). The antenna is positioned on a 33 mm x 30 mm flexible substrate with a thickness of 50 µm. Antenna properties, such as the far-field radiation patterns, scattering parameter S11 are provided. The presented compact, thin and flexible design along with excellent radiation characteristics are deemed suitable for integration into flexible and wearable devices.Keywords: Wearable Electronics, Slot Antenna, LTE, WLAN.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11931501 Monte Carlo Simulation of the Transport Phenomena in Degenerate Hg0.8Cd0.2Te
Authors: N. Dahbi, M. Daoudi, A.Belghachi
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The present work deals with the calculation of transport properties of Hg0.8Cd0.2Te (MCT) semiconductor in degenerate case. Due to their energy-band structure, this material becomes degenerate at moderate doping densities, which are around 1015 cm-3, so that the usual Maxwell-Boltzmann approximation is inaccurate in the determination of transport parameters. This problem is faced by using Fermi-Dirac (F-D) statistics, and the non-parabolic behavior of the bands may be approximated by the Kane model. The Monte Carlo (MC) simulation is used here to determinate transport parameters: drift velocity, mean energy and drift mobility versus electric field and the doped densities. The obtained results are in good agreement with those extracted from literature.Keywords: degeneracy case, Hg0.8Cd0.2Te semiconductor, Monte Carlo simulation, transport parameters.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18271500 Dynamic Stall Vortex Formation of OA-209 Airfoil at Low Reynolds Number
Authors: Aung Myo Thu, Sang Eon Jeon, Yung Hwan Byun, Soo Hyung Park
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The unsteady flow field around oscillating OA-209 airfoil at a Reynolds number of 3.5×105 were investigated. Three different reduced frequencies were tested in order to see how it affects the hysteresis loop of an airfoil. At a reduced frequency of 0.05 the deep dynamic stall phenomenon was observed. Lift overshooting was observed as a result of dynamic stall vortex (DSV) shedding. Further investigation was carried out to find out the cause of DSV formation and shedding over airfoil. Particle image velocimetry (PIV) and CFD tools were used and it was found out that dynamic stall separation (DSS), which is separated from leading edge separation (LES) and trailing edge separation (TES), triggered the dynamic stall vortex (DSV).
Keywords: Airfoil Flow, CFD, PIV, Dynamic Stall, Flow Separation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31741499 Mining Educational Data to Support Students’ Major Selection
Authors: Kunyanuth Kularbphettong, Cholticha Tongsiri
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This paper aims to create the model for student in choosing an emphasized track of student majoring in computer science at Suan Sunandha Rajabhat University. The objective of this research is to develop the suggested system using data mining technique to analyze knowledge and conduct decision rules. Such relationships can be used to demonstrate the reasonableness of student choosing a track as well as to support his/her decision and the system is verified by experts in the field. The sampling is from student of computer science based on the system and the questionnaire to see the satisfaction. The system result is found to be satisfactory by both experts and student as well.
Keywords: Data mining technique, the decision support system, knowledge and decision rules.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32841498 The Environmental Impact of Wireless Technologies in Nigeria: An Overview of the IoT and 5G Network
Authors: Powei Happiness Kerry
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Introducing wireless technologies in Nigeria have improved the quality of lives of Nigerians, however, not everyone sees it in that light. The paper on the environmental impact of wireless technologies in Nigeria summarizes the scholarly views on the impact of wireless technologies on the environment, beaming its searchlight on 5G and internet of things in Nigeria while also exploring the theory of the Technology Acceptance Model (TAM). The study used a qualitative research method to gather important data from relevant sources and contextually draws inference from the derived data. The study concludes that the Federal Government of Nigeria, before agreeing to any latest development in the world of wireless technologies, should weigh the implications and deliberate extensively with all stalk holders putting into consideration the confirmation it will receive from the National Assembly.Keywords: IoT, 5G, ICT, electromagnetic radiation, wave, field, radiofrequency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7861497 Optimization and Determination of Process Parameters in Thin Film SOI Photo-BJMOSFET
Authors: Hai-Qing Xie, Yun Zeng, Yong-Hong Yan, Guo-Liang Zhang, Tai-Hong Wang
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We propose photo-BJMOSFET (Bipolar Junction Metal-Oxide-Semiconductor Field Effect Transistor) fabricated on SOI film. ITO film is adopted in the device as gate electrode to reduce light absorption. I-V characteristics of photo-BJMOSFET obtained in dark (dark current) and under 570nm illumination (photo current) are studied furthermore to achieve high photo-to-dark-current contrast ratio. Two variables in the calculation were the channel length and the thickness of the film which were set equal to six different values, i.e., L=2, 4, 6, 8, 10, and 12μm and three different values, i.e., dsi =100, 200 and 300nm, respectively. The results indicate that the greatest photo-to-dark-current contrast ratio is achieved with L=10μm and dsi=200 nm at VGK=0.6V.
Keywords: Photo-to-dark-current contrast ratio, Photo-current, Dark-current, Process parameter
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14521496 The Effect of Harmonic Power Fluctuation for Estimating Flicker
Authors: Jin-Lung Guan, Ming-Ta Yang, Jhy-Cherng Gu, Hsin-Hung Chang, Chin-Lung Huang
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Voltage flicker problems have long existed in several of the distribution areas served by the Taiwan Power Company. In the past, those research results indicating that the estimated ΔV10 value based on the conventional method is significantly smaller than the survey value. This paper is used to study the relationship between the voltage flicker problems and harmonic power variation for the power system with electric arc furnaces. This investigation discussed thought the effect of harmonic power fluctuation with flicker estimate value. The method of field measurement, statistics and simulation is used. The survey results demonstrate that 10 ΔV estimate must account for the effect of harmonic power variation.Keywords: Voltage Flicker, Harmonic Power, EAF.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22091495 Single-Camera EKF-vSLAM
Authors: ML. Benmessaoud, A. Lamrani, K. Nemra, AK. Souici
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This paper presents an Extended Kaman Filter implementation of a single-camera Visual Simultaneous Localization and Mapping algorithm, a novel algorithm for simultaneous localization and mapping problem widely studied in mobile robotics field. The algorithm is vision and odometry-based, The odometry data is incremental, and therefore it will accumulate error over time, since the robot may slip or may be lifted, consequently if the odometry is used alone we can not accurately estimate the robot position, in this paper we show that a combination of odometry and visual landmark via the extended Kalman filter can improve the robot position estimate. We use a Pioneer II robot and motorized pan tilt camera models to implement the algorithm.Keywords: Mobile Robot, Navigation, vSLAM, EKF, monocular.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16811494 Soil Moisture Content in Hill-Filed Side Slope
Authors: A. Aboufayed
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The soil moisture content is an important property of the soil. The results of mean weekly gravimetric soil moisture content, measured for the three soil layers within the A horizon, showed that it was higher for the top 5 cm over the whole period of monitoring (15/7/2004 up to 10/11/05) with the variation becoming greater during winter time. This reflects the pattern of rainfall in Ireland which is spread over the whole year and shows that light rainfall events during summer time were compensated by loss through evapotranspiration, but only in the top 5 cm of soil. This layer had the highest porosity and highest moisture holding capacity due to the high content of organic matter. The gravimetric soil moisture contents of the top 5 cm and the underlying 5-15 and 15-25 cm layers show that bottom site of the Hill Field had higher soil moisture content than the middle and top sites during the whole period of monitoring.Keywords: Soil, Soil moisture, Gravimetric soil moisture content.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23731493 Implementing Learner-Centered Teaching Approach in Higher Education
Authors: Iman Ali Ahmed Al-Rashed
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This paper directs attention to the limitations of the teacher-centered strategy in teaching. The aim of this study is to draw more educational attention to learner-centered strategy in order to shift the emphasis from the traditional concept of teaching to a new concept in teaching. To begin bridging the traditional concept of teaching and the new concept, the study will explore the new concept of teaching to support teaching in Arab World generally and in Iraq specifically. A qualitative case study orientation was used to collect data in the form of classroom observations, interviews and field notes. The teaching practices used by three university instructors are investigated and according to the findings, some explanations and recommendations are made.Keywords: Case study, learner-centered strategy, qualitative study, teacher-centered strategy, traditional teaching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19951492 Proactive Approach to Innovation Management
Authors: Andrus Pedai, Igor Astrov
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The focus of this paper is to compare common approaches for Systems of Innovation (SI) and identify proactive alternatives for driving the innovation. Proactive approaches will also consider short and medium term perspectives with developments in the field of Computer Technology and Artificial Intelligence. Concerning Computer Technology and Large Connected Information Systems, it is reasonable to predict that during current or the next century intelligence and innovation will be separated from the constraints of human driven management. After this happens, humans will be no longer driving the innovation and there is possibility that SI for new intelligent systems will set its own targets and exclude humans. Over long time scale these developments could result in scenario, which will lead to the development of larger, cross galactic (universal) proactive SI and Intelligence.
Keywords: Artificial intelligence, DARPA, Moore’s law, proactive innovation, singularity, systems of innovation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20811491 Challenges to Enable Quick Start of an Environmental Monitoring with Wireless Sensor Network Technology
Authors: Masaki Ito, Hideyuki Tokuda, Takao Kawamura, Kazunori Sugahara
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With the advancement of wireless sensor network technology, its practical utilization is becoming an important challange. This paper overviews my past environmental monitoring project, and discusses the process of starting the monitoring by classifying it into four steps. The steps to start environmental monitoring can be complicated, but not well discussed by researchers of wireless sensor network technology. This paper demonstrates our activity and challenges in each of the four steps to ease the process, and argues future challenges to enable quick start of environmental monitoring.Keywords: Environmental Monitoring, Wireless Sensor Network, Field Experiment and Research Challenges.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19631490 Compressive Strength and Microstructure of Hybrid Alkaline Cements
Authors: Z. Abdollahnejad, P. Torgal, J. Barroso Aguiar
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Publications on the field of alkali-activated binders, state that this new material is likely to have high potential to become an alternative to Portland cement. Classical alkali-activated cements could be made more eco-efficient if the use of sodium silicate is avoided. Besides, most alkali-activated cements suffer from severe efflorescence originated by the fact that alkaline and/or soluble silicates that are added during processing cannot be totally consumed. This paper presents experimental results on hybrid alkaline cements. Compressive strength results and efflorescence’s observations show that the new mixes already analyzed are promising. SEM results show that no traditional porous ITZ was detected in these binders.
Keywords: Hybrid alkaline cements, Compressive strength, Efflorescence, SEM, ITZ.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21061489 On Estimating the Headcount Index by Using the Logistic Regression Estimator
Authors: Encarnación Álvarez, Rosa M. García-Fernández, Juan F. Muñoz, Francisco J. Blanco-Encomienda
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The problem of estimating a proportion has important applications in the field of economics, and in general, in many areas such as social sciences. A common application in economics is the estimation of the headcount index. In this paper, we define the general headcount index as a proportion. Furthermore, we introduce a new quantitative method for estimating the headcount index. In particular, we suggest to use the logistic regression estimator for the problem of estimating the headcount index. Assuming a real data set, results derived from Monte Carlo simulation studies indicate that the logistic regression estimator can be more accurate than the traditional estimator of the headcount index.
Keywords: Poverty line, poor, risk of poverty, sample, Monte Carlo simulations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20961488 Wave Vortex Parameters as an Indicator of Breaking Intensity
Authors: B. Robertson, K. Hall
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The study of the geometric shape of the plunging wave enclosed vortices as a possible indicator for the breaking intensity of ocean waves has been ongoing for almost 50 years with limited success. This paper investigates the validity of using the vortex ratio and vortex angle as methods of predicting breaking intensity. Previously published works on vortex parameters, based on regular wave flume results or solitary wave theory, present contradictory results and conclusions. Through the first complete analysis of field collected irregular wave breaking vortex parameters it is illustrated that the vortex ratio and vortex angle cannot be accurately predicted using standard breaking wave characteristics and hence are not suggested as a possible indicator for breaking intensity.
Keywords: Breaking Wave Measurement, Wave Vortex Parameters, Analytical Techniques, Ocean Remote Sensing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17681487 E-Procurement, the Golden Key to Optimizing the Supply Chains System
Authors: Somayeh Farzin, Hossein Teimoori Nezhad
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Procurement is an important component in the field of operating resource management and e-procurement is the golden key to optimizing the supply chains system. Global firms are optimistic on the level of savings that can be achieved through full implementation of e-procurement strategies. E-procurement is an Internet-based business process for obtaining materials and services and managing their inflow into the organization. In this paper, the subjects of supply chains and e-procurement and its benefits to organizations have been studied. Also, e-procurement in construction and its drivers and barriers have been discussed and a framework of supplier selection in an e-procurement environment has been demonstrated. This paper also has addressed critical success factors in adopting e-procurement in supply chains.Keywords: E-Procurement, Supply Chain, Benefits, Construction, Drivers, Barriers, Supplier Selection, CFSs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32331486 Bactericidal Properties of Carbohydrate-Stabilized Platinum Oxide Nanoparticles
Authors: Saeed Rezaei-Zarchi
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Platinum oxide nanoparticles were prepared by a simple hydrothermal route and chemical reduction using carbohydrates (Fructose and sucrose) as the reducing and stabilizing agents. The crystallite size of these nanoparticles was evaluated from X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM) and was found to be 10 nm as shown in figure 1, which is the demonstration of EM bright field and transmission electron microscopy. The effect of carbohydrates on the morphology of the nanoparticles was studied using TEM (Figure 1). The nanoparticles (100 μg/ml) were administered to the Pseudomonas Stutzeri and Lactobacillus cultures and the incubation was done at 35 oC for 24 hours. The nanocomposites exhibited interesting inhibitory as well as bactericidal activity against P. Stutzeri and and Lactobacillus species. Incorporation of nanoparticles also increased the thermal stability of the carbohydrates.Keywords: Platinum oxide, P. Stutzeri, Lactobacillus, bactericidal effect.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21141485 Motion Planning and Posture Control of the General 3-Trailer System
Authors: K. Raghuwaiya, B. Sharma, J. Vanualailai
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This paper presents a set of artificial potential field functions that improves upon, in general, the motion planning and posture control, with theoretically guaranteed point and posture stabilities, convergence and collision avoidance properties of the general3-trailer system in a priori known environment. We basically design and inject two new concepts; ghost walls and the distance optimization technique (DOT) to strengthen point and posture stabilities, in the sense of Lyapunov, of our dynamical model. This new combination of techniques emerges as a convenient mechanism for obtaining feasible orientations at the target positions with an overall reduction in the complexity of the navigation laws. Simulations are provided to demonstrate the effectiveness of the controls laws.
Keywords: Artificial potential fields, 3-trailer systems, motion planning, posture.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21511484 Application of Artificial Intelligence to Schedule Operability of Waterfront Facilities in Macro Tide Dominated Wide Estuarine Harbour
Authors: A. Basu, A. A. Purohit, M. M. Vaidya, M. D. Kudale
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Mumbai, being traditionally the epicenter of India's trade and commerce, the existing major ports such as Mumbai and Jawaharlal Nehru Ports (JN) situated in Thane estuary are also developing its waterfront facilities. Various developments over the passage of decades in this region have changed the tidal flux entering/leaving the estuary. The intake at Pir-Pau is facing the problem of shortage of water in view of advancement of shoreline, while jetty near Ulwe faces the problem of ship scheduling due to existence of shallower depths between JN Port and Ulwe Bunder. In order to solve these problems, it is inevitable to have information about tide levels over a long duration by field measurements. However, field measurement is a tedious and costly affair; application of artificial intelligence was used to predict water levels by training the network for the measured tide data for one lunar tidal cycle. The application of two layered feed forward Artificial Neural Network (ANN) with back-propagation training algorithms such as Gradient Descent (GD) and Levenberg-Marquardt (LM) was used to predict the yearly tide levels at waterfront structures namely at Ulwe Bunder and Pir-Pau. The tide data collected at Apollo Bunder, Ulwe, and Vashi for a period of lunar tidal cycle (2013) was used to train, validate and test the neural networks. These trained networks having high co-relation coefficients (R= 0.998) were used to predict the tide at Ulwe, and Vashi for its verification with the measured tide for the year 2000 & 2013. The results indicate that the predicted tide levels by ANN give reasonably accurate estimation of tide. Hence, the trained network is used to predict the yearly tide data (2015) for Ulwe. Subsequently, the yearly tide data (2015) at Pir-Pau was predicted by using the neural network which was trained with the help of measured tide data (2000) of Apollo and Pir-Pau. The analysis of measured data and study reveals that: The measured tidal data at Pir-Pau, Vashi and Ulwe indicate that there is maximum amplification of tide by about 10-20 cm with a phase lag of 10-20 minutes with reference to the tide at Apollo Bunder (Mumbai). LM training algorithm is faster than GD and with increase in number of neurons in hidden layer and the performance of the network increases. The predicted tide levels by ANN at Pir-Pau and Ulwe provides valuable information about the occurrence of high and low water levels to plan the operation of pumping at Pir-Pau and improve ship schedule at Ulwe.Keywords: Artificial neural network, back-propagation, tide data, training algorithm.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17121483 A Numerical Method for Diffusion and Cahn-Hilliard Equations on Evolving Spherical Surfaces
Authors: Jyh-Yang Wu, Sheng-Gwo Chen
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In this paper, we present a simple effective numerical geometric method to estimate the divergence of a vector field over a curved surface. The conservation law is an important principle in physics and mathematics. However, many well-known numerical methods for solving diffusion equations do not obey conservation laws. Our presented method in this paper combines the divergence theorem with a generalized finite difference method and obeys the conservation law on discrete closed surfaces. We use the similar method to solve the Cahn-Hilliard equations on evolving spherical surfaces and observe stability results in our numerical simulations.Keywords: Conservation laws, diffusion equations, Cahn-Hilliard Equations, evolving surfaces.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15051482 A Robust Controller for Output Variance Reduction and Minimum Variance with Application on a Permanent Field DC-Motor
Authors: Mahmood M. Al-Imam, M. Mustafa
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In this paper, we present an experimental testing for a new algorithm that determines an optimal controller-s coefficients for output variance reduction related to Linear Time Invariant (LTI) Systems. The algorithm features simplicity in calculation, generalization to minimal and non-minimal phase systems, and could be configured to achieve reference tracking as well as variance reduction after compromising with the output variance. An experiment of DCmotor velocity control demonstrates the application of this new algorithm in designing the controller. The results show that the controller achieves minimum variance and reference tracking for a preset velocity reference relying on an identified model of the motor.Keywords: Output variance, minimum variance, overparameterization, DC-Motor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1359