Search results for: critical path method
3002 Fatigue Crack Initiation and Propagation through Residual Stress Field
Authors: M. Benachour, N. Benachour, M. Benguediab
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In this paper fatigue crack initiation and propagation in notched plate under constant amplitude loading through tensile residual stress field of 2024 T351 Al-alloy plate were investigated. Residual stress field was generated by plastic deformation using finite element method (FEM) where isotropic hardening in Von Mises model was applied. Simulation of fatigue behavior was made on AFGROW code. It was shown that the fatigue crack initiation and propagation were affected by level of residual stress filed. In this investigation, the presence of tensile residual stresses at notch (hole) reduces considerably the total fatigue life. It was shown that the decreasing in stress reduces the fatigue crack growth rates.
Keywords: Residual stress, fatigue crack initiation, fatigue crack growth, Al-alloy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27183001 A Green Chemical Technique for the Synthesis of Magnetic Nanoparticles by Magnetotactic Bacteria
Authors: Parisa Tajer-Mohammad-Ghazvini, Rouha Kasra-Kermanshahi, Ahmad Nozad-Golikand, Majid Sadeghizadeh
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Bacterial magnetic nanoparticles have great useful potential in biotechnological and biomedical applications. In this study, a liquid growth medium was modified for cultivation a fastidious magnetotactic bacterium that has been isolated from Anzali lagoon, Iran in our previous research. These modifications include change in vitamin, mineral, carbon sources and etcetera. In our experience, the serum bottles and designed air-tight laboratory bottles were used to create microaerobic conditions in order to development of a method for scale-up experiment. This information may serve as a guide to green chemistry based biological protocols for the synthesis of magnetic nanoparticles with control over the chemical composition, morphology and size.Keywords: Green chemistry, Magnetosome, Magnetotactic bacteria, Magnetic nanoparticles, Nano-Biotechnology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 40333000 Fault Classification of a Doubly FED Induction Machine Using Neural Network
Authors: A. Ourici
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Rapid progress in process automation and tightening quality standards result in a growing demand being placed on fault detection and diagnostics methods to provide both speed and reliability of motor quality testing. Doubly fed induction generators are used mainly for wind energy conversion in MW power plants. This paper presents a detection of an inter turn stator and an open phase faults, in a doubly fed induction machine whose stator and rotor are supplied by two pulse width modulation (PWM) inverters. The method used in this article to detect these faults, is based on Park-s Vector Approach, using a neural network.Keywords: Doubly fed induction machine, inter turn stator fault, neural network, open phase fault, Park's vector approach, PWMinverter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16472999 Design and Optimization of a Microstrip Patch Antenna for Increased Bandwidth
Authors: Ankit Jain, Archana Agrawal
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With the ever-increasing need for wireless communication and the emergence of many systems, it is important to design broadband antennas to cover a wide frequency range. The aim of this paper is to design a broadband patch antenna, employing the three techniques of slotting, adding directly coupled parasitic elements, and fractal EBG structures. The bandwidth is improved from 9.32% to 23.77%. A wideband ranging from 4.15 GHz to 5.27 GHz is obtained. Also a comparative analysis of embedding EBG structures at different heights is also done. The composite effect of integrating these techniques in the design provides a simple and efficient method for obtaining low profile, broadband, high gain antenna. By the addition of parasitic elements the bandwidth was increased to only 18.04%. Later on by embedding EBG structures the bandwidth was increased up to 23.77%. The design is suitable for variety of wireless applications like WLAN and Radar Applications.
Keywords: Bandwidth, broadband, EBG structures, parasitic elements, Slotting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33922998 Proposal for Cost Calculation of Warehouse Processes and Its Usage for Setting Standards for Performance Evaluation
Authors: Tomas Cechura, Michal Simon
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This paper describes a proposal for cost calculation of warehouse processes and its usage for setting standards for performance evaluation. One of the most common options of monitoring process performance is benchmarking. The typical outcome is whether the monitored object is better or worse than an average or standard. Traditional approaches, however, cannot find any specific opportunities to improve performance or eliminate inefficiencies in processes. Higher process efficiency can be achieved for example by cost reduction assuming that the same output is generated. However, costs can be reduced only if we know their structure and we are able to calculate them accurately. In the warehouse process area it is rather difficult because in most cases we have available only aggregated values with low explanatory ability. The aim of this paper is to create a suitable method for calculating the storage costs. At the end is shown a practical example of process calculation.
Keywords: Calculation, Costs, Performance, Process, Warehouse.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 93242997 A Systematic Method for Performance Analysis of SOA Applications
Authors: Marzieh Asgarnezhad, Ramin Nasiri, Abdollah Shahidi
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The successful implementation of Service-Oriented Architecture (SOA) is not confined to Information Technology systems and required changes of the whole enterprise. In order to adapt IT and business, the enterprise requires adequate and measurable methods. The adoption of SOA creates new problem with regard to measuring and analysis the performance. In fact the enterprise should investigate to what extent the development of services will increase the value of business. It is required for every business to measure the extent of SOA adaptation with the goals of enterprise. Moreover, precise performance metrics and their combination with the advanced evaluation methodologies as a solution should be defined. The aim of this paper is to present a systematic methodology for designing a measurement system at the technical and business levels, so that: (1) it will determine measurement metrics precisely (2) the results will be analysed by mapping identified metrics to the measurement tools.
Keywords: Service-oriented architecture, metrics, performance, evaluation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17932996 Comparison of Prognostic Models in Different Scenarios of Shoreline Position on Ponta Negra Beach in Northeastern Brazil
Authors: Débora V. Busman, Venerando E. Amaro, Mattheus da C. Prudêncio
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Prognostic studies of the shoreline are of utmost importance for Ponta Negra Beach, located in Natal, Northeastern Brazil, where the infrastructure recently built along the shoreline is severely affected by flooding and erosion. This study compares shoreline predictions using three linear regression methods (LMS, LRR and WLR) and tries to discern the best method for different shoreline position scenarios. The methods have shown erosion on the beach in each of the scenarios tested, even in less intense dynamic conditions. The WLA_A with confidence interval of 95% was the well-adjusted model and calculated a retreat of -1.25 m/yr to -2.0 m/yr in hot spot areas. The change of the shoreline on Ponta Negra Beach can be measured as a negative exponential curve. Analysis of these methods has shown a correlation with the morphodynamic stage of the beach.
Keywords: Coastal Erosion, Prognostic Model, DSAS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25822995 Performance Evaluation of Single Basin Solar Still
Authors: Prem Singh, Jagdeep Singh
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In an attempt to investigate the performance of single basin solar still for climate conditions of Ludhiana a single basin solar still was designed, fabricated and tested. The energy balance equations for various parts of the still are solved by Gauss-Seidel iteration method. Computer model was made and experimentally validated. The validated computer model was used to estimate the annual distillation yield and performance ratio of the still for Ludhiana. The Theoretical and experimental distillation yield were 4318.79 ml and 3850 ml respectively for the typical day. The predicted distillation yield was 12.5% higher than the experimental yield. The annual distillation yield per square metre aperture area and annual performance ratio for single basin solar still is 1095 litres and 0.43 respectively. The payback period for micro-stepped solar still is 2.5 years.Keywords: Solar distillation, solar still, single basin, still.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30932994 Extended Release System of Hypoglycemic Agent Containing Solid Dispersions: Strategies and Mechanisms
Authors: Amit Kumar, Ramendeep Grawal, Peeyush Sharma, Dinesh Puri, Anil Bhandari
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The main perspective of the present study aims at overcoming solubility problems by using the technique of solid dispersion. Repaglinide is a BCS Class II drug, having low aqueous solubility and therefore, low bioavailability. Solid dispersions of repaglinide with different carriers Polyvinyl Pyrrolidone (PVP) and Ethyl Cellulose (EC) in different ratios were prepared by suspending method and Dissolving methods. In vitro release studies revealed that the F7 formulation showed extended drug release. So, the dissolution profile of solid dispersion containing EC and PVP K30 (1: 3) was selected as the best formulation because of its extended drug release among all formulations. In conclusion, solid dispersions of Repaglinide in PVP have shown to be a promising approach to improve the bioavailability of Repaglinide.
Keywords: Ethyl Cellulose, Glibenclamide, Polyvinyl Pyrrolidone, Repaglinide, Solid Dispersion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26422993 Possibilities of Sewage Sludge Application in the Conditions of Slovak Republic
Authors: Peter Takáč, Dana Šimová, Terézia Szabová, Tomáš Bakalár
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The direct sewage sludge application is a relative cheap method for their liquidation. In the past heavy metal contents increase in soils treated with sewage sludge was observed. In 2003 there was acceptance on act n.188/2003 about sewage sludge application on soils. The basic philosophy of act is a safety of the environmental proof of sludge application on soils. The samples of soils from wastewater treatment plant (WTP) Poprad (35) and WTP Michalovce (33 samples) were analyzed which were chosen for sludge application on soils. According to the results only 14 areas for Poprad and 25 areas for Michalovce are suitable for sludge application according to act No. 188/2003. The application dose of sludge was calculated 50 t.ha-1 or 75 t. ha-1 once in 5 years to ensure that heavy metal contents in treated soils will be kept.Keywords: Environmental safety, heavy metals in soils, sewagesludge application.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13842992 Creativity: A Motivational Tool for Interest and Conceptual Understanding in Science Education
Authors: Thienhuong Hoang
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This qualitative, quantitative mixed-method study explores how students- motivation and interest in creative hands-on activities affected their conceptual understanding of science. The objectives of this research include developing a greater understanding about how creative activities, incorporated into the classroom as instructional strategies, increase student motivation and their learning or mastery of science concepts. The creative activities are viewed as a motivational tool, a specific type of task, which have an impact on student goals. Pre-and-post tests, pre-and-post interviews, and student responses measure motivational-goal theory variables, interest in the activity, and conceptual change. Implications for education and future research will be discussed.
Keywords: Science education, motivation, conceptual understanding, instructional strategies.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18032991 Comparative Analysis of Vibration between Laminated Composite Plates with and without Holes under Compressive Loads
Authors: Bahi-Eddine Lahouel, Mohamed Guenfoud
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In this study, a vibration analysis was carried out of symmetric angle-ply laminated composite plates with and without square hole when subjected to compressive loads, numerically. A buckling analysis is also performed to determine the buckling load of laminated plates. For each fibre orientation, the compression load is taken equal to 50% of the corresponding buckling load. In the analysis, finite element method (FEM) was applied to perform parametric studies, the effects of degree of orthotropy and stacking sequence upon the fundamental frequencies and buckling loads are discussed. The results show that the presence of a constant compressive load tends to reduce uniformly the natural frequencies for materials which have a low degree of orthotropy. However, this reduction becomes non-uniform for materials with a higher degree of orthotropy.Keywords: Vibration, Buckling, Cutout, Laminated composite, FEM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20552990 A Parametric Study on Deoiling Hydrocyclones Flow Field
Authors: Maysam Saidi, Reza Maddahian, Bijan Farhanieh
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Hydrocyclones flow field study is conducted by performing a parametric study. Effect of cone angle on deoiling hydrocyclones flow behaviour is studied in this research. Flow field of hydrocyclone is obtained by three-dimensional simulations with OpenFOAM code. Because of anisotropic behaviour of flow inside hydrocyclones LES is a suitable method to predict the flow field since it resolves large scales and model isotropic small scales. Large eddy simulation is used to predict the flow behavior of three different cone angles. Differences in tangential velocity and pressure distribution are reported in some figures.
Keywords: Deoiling hydrocyclones, Flow field, Hydrocyclone cone angle, Large Eddy Simulation, Pressure distribution
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24202989 Terrorism as a Threat to International Peace: A Study on 9/11 Terrorism
Authors: Aftab
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This paper is a theory-oriented study that seeks to generalize the process through which terrorism leads to the disruption of international peace. For this, it scrutinizes 9/11 terrorism based on five analytical domains of threat—security disorder, political tensions, economic adversity, socio-ideological intolerance, and the fear and cost of counterterrorism—each of which is explored in light of specific indicators. By applying qualitative correlation method, the paper finds that terrorism immediately entails five distinct kinds of negative impacts that lead to both internal disorders caused by state weakness and global disorder caused by international tensions, which in consequence, causes international peace to be disrupted. Thus, in following inductive process, the findings of this paper help to make a general inference that terrorism is a threat to international peace.
Keywords: Domains, global disorder, internal disorder, international peace, terrorism, threat.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7932988 Seismic Fragility for Sliding Failure of Weir Structure Considering the Process of Concrete Aging
Authors: HoYoung Son, Ki Young Kim, Woo Young Jung
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This study investigated the change of weir structure performances when durability of concrete, which is the main material of weir structure, decreased due to their aging by mean of seismic fragility analysis. In the analysis, it was assumed that the elastic modulus of concrete was reduced by 10% in order to account for their aged deterioration. Additionally, the analysis of seismic fragility was based on Monte Carlo Simulation method combined with a 2D nonlinear finite element in ABAQUS platform with the consideration of deterioration of concrete. Finally, the comparison of seismic fragility of model pre- and post-deterioration was made to study the performance of weir. Results show that the probability of failure in moderate damage for deteriorated model was found to be larger than pre-deterioration model when peak ground acceleration (PGA) passed 0.4 g.Keywords: Weir, FEM, concrete, fragility, aging.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9202987 A Study on Creation of Human-Based Co-Design Service Platform
Authors: Chiung-Hui Chen
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With the approaching of digital era, various interactive service platforms and systems support human beings- needs in lives by different contents and measures. Design strategies have gradually turned from function-based to user-oriented, and are often customized. In other words, how designers include users- value reaction in creation becomes the goal. Creative design service of interior design requires positive interaction and communication to allow users to obtain full design information, recognize the style and process of personal needs, develop creative service design, lower communication time and cost and satisfy users- sense of achievement. Thus, by constructing a co-design method, based on the communication between interior designers and users, this study recognizes users- real needs and provides the measure of co-design for designers and users.Keywords: Co-Design, Customized, Design Service, Interactive Genetic Algorithm, Interior Design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14962986 Phenols and Manganese Removal from Landfill Leachate and Municipal Wastewater Using the Constructed Wetland
Authors: Amin Mojiri, Lou Ziyang
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Constructed Wetland (CW) is a reasonable method to treat wastewater. Current study was carried out to co-treat landfill leachate and domestic wastewater using a CW system. Typha domingensis was transplanted to CW, which encloses two substrate layers of adsorbents named ZELIAC and zeolite. Response surface methodology and central composite design were employed to evaluate experimental data. Contact time (h) and leachate-towastewater mixing ratio (%; v/v) were selected as independent factors. Phenols and manganese removal were selected as dependent responses. At optimum contact time (48.7 h) and leachate-towastewater mixing ratio (20.0%), removal efficiencies of phenols and manganese removal efficiencies were 90.5%, and 89.4%, respectively.Keywords: Constructed wetland, manganese, phenols, Thypha domingensis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23192985 Jigger Flea (Tunga penetrans) Infestations and Use of Soil-Cow Dung-Ash Mixture as a Flea Control Method in Eastern Uganda
Authors: Gerald Amatre, Julius Bunny Lejju, Morgan Andama
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Despite several interventions, jigger flea infestations continue to be reported in the Busoga sub-region in Eastern Uganda. The purpose of this study was to identify factors that expose the indigenous people to jigger flea infestations and evaluate the effectiveness of any indigenous materials used in flea control by the affected communities. Flea compositions in residences were described, factors associated with flea infestation and indigenous materials used in flea control were evaluated. Field surveys were conducted in the affected communities after obtaining preliminary information on jigger infestation from the offices of the District Health Inspectors to identify the affected villages and households. Informed consent was then sought from the local authorities and household heads to conduct the study. Focus group discussions were conducted with key district informants, namely, the District Health Inspectors, District Entomologists and representatives from the District Health Office. A GPS coordinate was taken at central point at every household enrolled. Fleas were trapped inside residences using Kilonzo traps. A Kilonzo Trap comprised a shallow pan, about three centimetres deep, filled to the brim with water. The edges of the pan were smeared with Vaseline to prevent fleas from crawling out. Traps were placed in the evening and checked every morning the following day. The trapped fleas were collected in labelled vials filled with 70% aqueous ethanol and taken to the laboratory for identification. Socio-economic and environmental data were collected. The results indicate that the commonest flea trapped in the residences was the cat flea (Ctenocephalides felis) (50%), followed by Jigger flea (Tunga penetrans) (46%) and rat flea (Xenopsylla Cheopis) (4%), respectively. The average size of residences was seven squire metres with a mean of six occupants. The residences were generally untidy; with loose dusty floors and the brick walls were not plastered. The majority of the jigger affected households were headed by peasants (86.7%) and artisans (13.3%). The household heads mainly stopped at primary school level (80%) and few at secondary school level (20%). The jigger affected households were mainly headed by peasants of low socioeconomic status. The affected community members use soil-cow dung-ash mixture to smear floors of residences as the only measure to control fleas. This method was found to be ineffective in controlling the insects. The study recommends that home improvement campaigns be continued in the affected communities to improve sanitation and hygiene in residences as one of the interventions to combat flea infestations. Other cheap, available and effective means should be identified to curb jigger flea infestations.
Keywords: Cow dung-soil-ash mixture, infestations, Jigger flea, Tunga penetrans.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8832984 Direct Design of Steel Bridge Using Nonlinear Inelastic Analysis
Authors: Boo-Sung Koh, Seung-Eock Kim
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In this paper, a direct design using a nonlinear inelastic analysis is suggested. Also, this paper compares the load carrying capacity obtained by a nonlinear inelastic analysis with experiment results to verify the accuracy of the results. The allowable stress design results of a railroad through a plate girder bridge and the safety factor of the nonlinear inelastic analysis were compared to examine the safety performance. As a result, the load safety factor for the nonlinear inelastic analysis was twice as high as the required safety factor under the allowable stress design standard specified in the civil engineering structure design standards for urban magnetic levitation railways, which further verified the advantages of the proposed direct design method.
Keywords: Direct design, nonlinear inelastic analysis, residual stress, initial geometric imperfection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14552983 Optimized Multiplier Based upon 6-Input Luts and Vedic Mathematics
Authors: Zulhelmi Zakaria, Shuja A. Abbasi
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A new approach has been used for optimized design of multipliers based upon the concepts of Vedic mathematics. The design has been targeted to state-of-the art field-programmable gate arrays (FPGAs). The multiplier generates partial products using Vedic mathematics method by employing basic 4x4 multipliers designed by exploiting 6-input LUTs and multiplexers in the same slices resulting in drastic reduction in area. The multiplier is realized on Xilinx FPGAs using devices Virtex-5 and Virtex-6.Carry Chain Adder was employed to obtain final products. The performance of the proposed multiplier was examined and compared to well-known multipliers such as Booth, Carry Save, Carry ripple, and array multipliers. It is demonstrated that the proposed multiplier is superior in terms of speed as well as power consumption.
Keywords: Multiplier, Vedic Mathematics, LUTs, FPGAs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29242982 Kernel’s Parameter Selection for Support Vector Domain Description
Authors: Mohamed EL Boujnouni, Mohamed Jedra, Noureddine Zahid
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Support Vector Domain Description (SVDD) is one of the best-known one-class support vector learning methods, in which one tries the strategy of using balls defined on the feature space in order to distinguish a set of normal data from all other possible abnormal objects. As all kernel-based learning algorithms its performance depends heavily on the proper choice of the kernel parameter. This paper proposes a new approach to select kernel's parameter based on maximizing the distance between both gravity centers of normal and abnormal classes, and at the same time minimizing the variance within each class. The performance of the proposed algorithm is evaluated on several benchmarks. The experimental results demonstrate the feasibility and the effectiveness of the presented method.
Keywords: Gravity centers, Kernel’s parameter, Support Vector Domain Description, Variance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18312981 Managing, Sustaining, and Future Proofing the Business of Educational Provision Following Large-Scale Disaster and Disruption
Authors: Judy Yarwood, Lesley Seaton, Philippa Seaton
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A catastrophic earthquake measuring 6.3 on the Richter scale struck the Christchurch, New Zealand Central Business District on February 22, 2012, abruptly disrupting the business of teaching and learning at Christchurch Polytechnic Institute of Technology. This paper presents the findings from a study undertaken about the complexity of delivering an educational programme in the face of this traumatic natural event. Nine interconnected themes emerged from this multiple method study: communication, decision making, leader- and follower-ship, balancing personal and professional responsibilities, taking action, preparedness and thinking ahead, all within a disruptive and uncertain context. Sustainable responses that maximise business continuity, and provide solutions to practical challenges, are among the study-s recommendations.Keywords: Business continuity, earthquake, education, sustainability
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19032980 Application of SDS/LABS in Recovery Improvement from Fractured Models
Authors: Rasool Razmi, Mohammad Hossein Sedaghat, Reza Janamiri, Amir Hatampou
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This work concerns on experimentally investigation of surfactant flooding in fractured porous media. In this study a series of water and surfactant injection processes were performed on micromodels initially saturated with a heavy crude oil. Eight fractured glass micromodels were used to illustrate effects of surfactant types and concentrations on oil recovery efficiency in presence of fractures with different properties i.e. fracture orientation, length and number of fractures. Two different surfactants with different concentrations were tested. The results showed that surfactant flooding would be more efficient by using SDS surfactant aqueous solution and also by locating injection well in a proper position respect to fracture properties. This study demonstrates different physical and chemical conditions that affect the efficiency of this method of enhanced oil recovery.Keywords: Displacement, Fractured five-spot systems, Heavy oil, Surfactant flooding.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18942979 Knowledge Acquisition for the Construction of an Evolving Ontology: Application to Augmented Surgery
Authors: Nora Taleb, Sellami Mokhtar, Michel Simonet
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This work concerns the evolution and the maintenance of an ontological resource in relation with the evolution of the corpus of texts from which it had been built. The knowledge forming a text corpus, especially in dynamic domains, is in continuous evolution. When a change in the corpus occurs, the domain ontology must evolve accordingly. Most methods manage ontology evolution independently from the corpus from which it is built; in addition, they treat evolution just as a process of knowledge addition, not considering other knowledge changes. We propose a methodology for managing an evolving ontology from a text corpus that evolves over time, while preserving the consistency and the persistence of this ontology. Our methodology is based on the changes made on the corpus to reflect the evolution of the considered domain - augmented surgery in our case. In this context, the results of text mining techniques, as well as the ARCHONTE method slightly modified, are used to support the evolution process.Keywords: Corpus, Evolution, Ontology
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14432978 Cost and Profit Analysis of Markovian Queuing System with Two Priority Classes: A Computational Approach
Authors: S. S. Mishra, D. K. Yadav
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This paper focuses on cost and profit analysis of single-server Markovian queuing system with two priority classes. In this paper, functions of total expected cost, revenue and profit of the system are constructed and subjected to optimization with respect to its service rates of lower and higher priority classes. A computing algorithm has been developed on the basis of fast converging numerical method to solve the system of non linear equations formed out of the mathematical analysis. A novel performance measure of cost and profit analysis in view of its economic interpretation for the system with priority classes is attempted to discuss in this paper. On the basis of computed tables observations are also drawn to enlighten the variational-effect of the model on the parameters involved therein.Keywords: Cost and Profit, Computing, Expected Revenue, Priority classes
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27162977 Solar Tracking System Using a Refrigerant as Working Medium for Solar Energy Conversion
Authors: S. Sendhil Kumar, S. N. Vijayan
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Utilization of solar energy can be found in various domestic and industrial applications. The performance of any solar collector is largely affected by various parameters such as glazing, absorber plate, top covers, and heating pipes. Technology improvements have brought us another method for conversion of solar energy to direct electricity using solar photovoltaic system. Utilization and extraction of solar energy is the biggest problem in these conversion methods. This paper aims to overcome these problems and take the advantages of available energy from solar by maximizing the utilization through solar tracking system using a refrigerant as a working medium. The use of this tracking system can help increase the efficiency of conversion devices by maximum utilization of solar energy. The dual axis tracking system gives maximum energy output compared to single axis tracking system.Keywords: Refrigerant, solar collector, solar energy, solar panel, solar tracking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20202976 Investigating Relationship between Product Features and Supply Chain Integration
Authors: Saied Rasul Hosseini Baharanchi
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This paper addresses integration issues in supply chain, and tries to investigate how different aspects of integration are linked with some product features. Integration in this study is interpreted as "internal", "upstream" (supply), and "downstream" (demand). Two features of product innovative and quality are considered. To examine the relationships between supply chain integrations – as mentioned above, and product features, this research follows the survey method in automotive industry.The results imply that supply chain upstream integration has a higher impact on product quality, comparing to internal and supply chain downstream integrations. It is also found that the influence of supply chain downstream integration on product innovation is greater than other variables. In brief, this study mainly tackles the importance of specific level of supply chain integrations and its effects on two product features.Keywords: Supply chain upstream integration, supply chaindownstream integration, internal integration, product features
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18302975 Modeling Converters during the Warm-up Period for Hydrocarbon Oxidation
Authors: Sanchita Chauhan, V.K. Srivastava
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Catalytic converters are used for minimizing the release of pollutants to the atmosphere. It is during the warm-up period that hydrocarbons are seen to be released in appreciable quantities from these converters. In this paper the conversion of a fast oxidizing hydrocarbon propylene is analysed using two numerical methods. The quasi steady state method assumes the accumulation terms to be negligible in the gas phase mass and energy balance equations, however this term is present in the solid phase energy balance. The unsteady state model accounts for the accumulation term to be present in the gas phase mass and energy balance and in the solid phase energy balance. The results derived from the two models for gas concentration, gas temperature and solid temperature are compared.
Keywords: Propylene, catalyst, quasi steady state, unsteady state.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15922974 Research on the Mode and Strategy of Urban Renewal in the Old Urban Area of China: A Case Study of Chongqing City
Authors: Sun Ailu, Zhao Wanmin
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In the process of rapid urbanization, old urban renewal is an important task in China's urban construction. This study, using status survey and Analytic Hierarchy Process (AHP) method, taking Chongqing of China as an example, puts forward the problems faced by the old urban area from the aspects of function, facilities and environment. Further, this study summarizes the types of the old urban area and proposes space renewal strategies for three typical old urban areas, such as old residential area, old factory and old market. These old urban areas are confronted with the problems of functional layout confounding, lack of infrastructure and poor living environment. At last, this paper proposes spatial strategies for urban renewal, which are hoped to be useful for urban renewal management in China.
Keywords: Old urban renewal, renewal mode, renewal strategy, Chongqing, China.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7352973 Signal Processing Approach to Study Multifractality and Singularity of Solar Wind Speed Time Series
Authors: Tushnik Sarkar, Mofazzal H. Khondekar, Subrata Banerjee
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This paper investigates the nature of the fluctuation of the daily average Solar wind speed time series collected over a period of 2492 days, from 1st January, 1997 to 28th October, 2003. The degree of self-similarity and scalability of the Solar Wind Speed signal has been explored to characterise the signal fluctuation. Multi-fractal Detrended Fluctuation Analysis (MFDFA) method has been implemented on the signal which is under investigation to perform this task. Furthermore, the singularity spectra of the signals have been also obtained to gauge the extent of the multifractality of the time series signal.Keywords: Detrended fluctuation analysis, generalized Hurst exponent, holder exponents, multifractal exponent, multifractal spectrum, singularity spectrum, time series analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1314