Search results for: safety analysis
8368 Maintenance Dredging at Port of Townsville
Authors: M. Jaditager, J. Lovisa, N. Sivakugan
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The Port of Townsville conducts regular annual maintenance dredging to maintain depths of its harbor basin and approach channels for the navigational safety of the vessels against the natural accumulation of marine sediments. In addition to the regular maintenance dredging, the port undertakes emergency dredging in cases where large quantities of sediments are mobilized and deposited in port waters by cyclone or major flood events. The maintenance dredging material derived from the port may be disposed at sea or on land in accordance with relevant state and commonwealth regulations. For the land disposal, the dredged mud slurry is hydraulically placed into containment ponds and left to undergo sedimentation and self-weight consolidation to form fill material for land reclamation. This paper provides an overview of the maintenance dredging at the Port of Townsville and emphasis on maintenance dredging requirements, sediment quality, bathymetry, dredging methods used, and dredged material disposal options.
Keywords: Consolidation, dredged material, maintenance dredging, marine sediments, sedimentation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24508367 Molecular Characterization of Free Radicals Decomposing Genes on Plant Developmental Stages
Authors: R. Haddad, K. Morris, V. Buchanan-Wollaston
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Biochemical and molecular analysis of some antioxidant enzyme genes revealed different level of gene expression on oilseed (Brassica napus). For molecular and biochemical analysis, leaf tissues were harvested from plants at eight different developmental stages, from young to senescence. The levels of total protein and chlorophyll were increased during maturity stages of plant, while these were decreased during the last stages of plant growth. Structural analysis (nucleotide and deduced amino acid sequence, and phylogenic tree) of a complementary DNA revealed a high level of similarity for a family of Catalase genes. The expression of the gene encoded by different Catalase isoforms was assessed during different plant growth phase. No significant difference between samples was observed, when Catalase activity was statistically analyzed at different developmental stages. EST analysis exhibited different transcripts levels for a number of other relevant antioxidant genes (different isoforms of SOD and glutathione). The high level of transcription of these genes at senescence stages was indicated that these genes are senescenceinduced genes.Keywords: Biochemical analysis, Oilseed, Expression pattern, Growth phases
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15538366 Statistical Analysis of First Order Plus Dead-time System using Operational Matrix
Authors: Pham Luu Trung Duong, Moonyong Lee
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To increase precision and reliability of automatic control systems, we have to take into account of random factors affecting the control system. Thus, operational matrix technique is used for statistical analysis of first order plus time delay system with uniform random parameter. Examples with deterministic and stochastic disturbance are considered to demonstrate the validity of the method. Comparison with Monte Carlo method is made to show the computational effectiveness of the method.
Keywords: First order plus dead-time, Operational matrix, Statistical analysis, Walsh function.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13708365 Development of a Tilt-Rotor Aircraft Model Using System Identification Technique
Authors: Antonio Vitale, Nicola Genito, Giovanni Cuciniello, Ferdinando Montemari
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The introduction of tilt-rotor aircraft into the existing civilian air transportation system will provide beneficial effects due to tilt-rotor capability to combine the characteristics of a helicopter and a fixed-wing aircraft into one vehicle. The disposability of reliable tilt-rotor simulation models supports the development of such vehicle. Indeed, simulation models are required to design automatic control systems that increase safety, reduce pilot's workload and stress, and ensure the optimal aircraft configuration with respect to flight envelope limits, especially during the most critical flight phases such as conversion from helicopter to aircraft mode and vice versa. This article presents a process to build a simplified tilt-rotor simulation model, derived from the analysis of flight data. The model aims to reproduce the complex dynamics of tilt-rotor during the in-flight conversion phase. It uses a set of scheduled linear transfer functions to relate the autopilot reference inputs to the most relevant rigid body state variables. The model also computes information about the rotor flapping dynamics, which are useful to evaluate the aircraft control margin in terms of rotor collective and cyclic commands. The rotor flapping model is derived through a mixed theoretical-empirical approach, which includes physical analytical equations (applicable to helicopter configuration) and parametric corrective functions. The latter are introduced to best fit the actual rotor behavior and balance the differences existing between helicopter and tilt-rotor during flight. Time-domain system identification from flight data is exploited to optimize the model structure and to estimate the model parameters. The presented model-building process was applied to simulated flight data of the ERICA Tilt-Rotor, generated by using a high fidelity simulation model implemented in FlightLab environment. The validation of the obtained model was very satisfying, confirming the validity of the proposed approach.
Keywords: Flapping Dynamics, Flight Dynamics, System Identification, Tilt-Rotor Modeling and Simulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12908364 A Method for Evaluating the Mechanical Stress on Mandibular Advancement Devices
Authors: Tsung-yin Lin, Yi-yu Lee, Ching-hua Hung
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This study focuses on the stress analysis of Mandibular Advancement Devices (MADs), which are considered as a standard treatment of snoring that promoted by American Academy of Sleep Medicine (AASM). Snoring is the most significant feature of sleep-disordered breathing (SDB). SDB will lead to serious problems in human health. Oral appliances are ensured in therapeutic effect and compliance, especially the MADs. This paper proposes a new MAD design, and the finite element analysis (FEA) is introduced to precede the stress simulation for this MAD.Keywords: Finite element analysis, mandibular advancement devices, mechanical stress, snoring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18988363 ATM Location Problem and Cash Management in Automated Teller Machines
Authors: M. Erol Genevois, D. Celik, H. Z. Ulukan
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Automated Teller Machines (ATMs) can be considered among one of the most important service facilities in the banking industry. The investment in ATMs and the impact on the banking industry is growing steadily in every part of the world. The banks take into consideration many factors like safety, convenience, visibility, and cost in order to determine the optimum locations of ATMs. Today, ATMs are not only available in bank branches but also at retail locations. Another important factor is the cash management in ATMs. A cash demand model for every ATM is needed in order to have an efficient cash management system. This forecasting model is based on historical cash demand data which is highly related to the ATMs location. So, the location and the cash management problem should be considered together. This paper provides a general review on studies, efforts and development in ATMs location and cash management problem.Keywords: ATM location problem, cash management problem, ATM cash replenishment problem, literature review in ATMs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 52618362 Reliability Based Optimal Design of Laterally Loaded Pile with Limited Residual Strain Energy Capacity
Authors: M. Movahedi Rad
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In this study, a general approach to the reliability based limit analysis of laterally loaded piles is presented. In engineering practice the uncertainties play a very important role. The aim of this study is to evaluate the lateral load capacity of free-head and fixed-head long pile when plastic limit analysis is considered. In addition to the plastic limit analysis to control the plastic behaviour of the structure, uncertain bound on the complementary strain energy of the residual forces is also applied. This bound has significant effect for the load parameter. The solution to reliability-based problems is obtained by a computer program which is governed by the reliability index calculation.Keywords: Reliability, laterally loaded pile, residual strain energy, probability, limit analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19048361 Comprehensive Studies on Mechanical Stress Analysis of Functionally Graded Plates
Authors: Kyung-Su Na, Ji-Hwan Kim
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Stress analysis of functionally graded composite plates composed of ceramic, functionally graded material and metal layers is investigated using 3-D finite element method. In FGM layer, material properties are assumed to be varied continuously in the thickness direction according to a simple power law distribution in terms of the volume fraction of a ceramic and metal. The 3-D finite element model is adopted by using an 18-node solid element to analyze more accurately the variation of material properties in the thickness direction. Numerical results are compared for three types of materials. In the analysis, the tensile and the compressive stresses are summarized for various FGM thickness ratios, volume fraction distributions, geometric parameters and mechanical loads.Keywords: Functionally graded materials, Stress analysis, 3-D finite element method
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17448360 Impact of Node Density and Transmission Range on the Performance of OLSR and DSDV Routing Protocols in VANET City Scenarios
Authors: Yassine Meraihi, Dalila Acheli, Rabah Meraihi
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Vehicular Ad hoc Network (VANET) is a special case of Mobile Ad hoc Network (MANET) used to establish communications and exchange information among nearby vehicles and between vehicles and nearby fixed infrastructure. VANET is seen as a promising technology used to provide safety, efficiency, assistance and comfort to the road users. Routing is an important issue in Vehicular Ad Hoc Network to find and maintain communication between vehicles due to the highly dynamic topology, frequently disconnected network and mobility constraints.
This paper evaluates the performance of two most popular proactive routing protocols OLSR and DSDV in real city traffic scenario on the basis of three metrics namely Packet delivery ratio, throughput and average end to end delay by varying vehicles density and transmission range.
Keywords: DSDV, OLSR, Quality of service, Routing protocols, VANET.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22778359 New Approach to Spectral Analysis of High Bit Rate PCM Signals
Authors: J. P. Dubois
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Pulse code modulation is a widespread technique in digital communication with significant impact on existing modern and proposed future communication technologies. Its widespread utilization is due to its simplicity and attractive spectral characteristics. In this paper, we present a new approach to the spectral analysis of PCM signals using Riemann-Stieltjes integrals, which is very accurate for high bit rates. This approach can serve as a model for similar spectral analysis of other competing modulation schemes.Keywords: Coding, discrete Fourier, power spectral density, pulse code modulation, Riemann-Stieltjes integrals.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15938358 Regional Aircraft Selection Using Preference Analysis for Reference Ideal Solution (PARIS)
Authors: C. Ardil
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The paper presents a multiple criteria decision making analysis process to determine the most suitable regional aircraft type according to a set of evaluation criteria. The main purpose of this study is to use different decision making methods to determine the most suitable regional aircraft for aviation operators. In this context, the nine regional aircraft types were analyzed using multiple criteria decision making analysis methods. Preference analysis for reference ideal solution (PARIS) was used in regional aircraft selection process. The findings of the proposed model show that the ranking results of the multiple criteria decision making models are consistent with each other, and the proposed method is efficient, and the results are valid. Finally, the Embraer E195-E2 model regional aircraft is chosen as the most suitable aircraft type.
Keywords: aircraft, regional aircraft selection, multiple criteria decision making, multiple criteria decision making analysis, mean weight, entropy weight, MCDMA, PARIS
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4528357 The Influences of Marketplace Knowledge, General Product Class Knowledge, and Knowledge in Meat Product with Traceability on Trust in Meat Traceability
Authors: Kawpong Polyorat
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Since the outbreak of mad cow disease and bird flu, consumers have become more concerned with meat quality and safety. As a result, meat traceability is adopted as one approach to handle consumers’ concern in this issue. Nevertheless, in Thailand, meat traceability is rarely used as a marketing tool to persuade consumers. As a consequence, the present study attempts to understand consumer trust in the meat traceability system by conducting a study in this country to examine the impact of three types of consumer knowledge on this trust. The study results reveal that out of three types of consumer knowledge, marketplace knowledge was the sole predictor of consumer trust in meat traceability and it has a positive influence. General product class knowledge and knowledge in meat products with traceability, however, did not significantly influence consumer trust. The research results provide several implications and directions for future study.Keywords: Consumer knowledge, marketing, product knowledge, traceability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10948356 Spatial Distribution and Risk Assessment of As, Hg, Co and Cr in Kaveh Industrial City, using Geostatistic and GIS
Authors: Abbas Hani
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The concentrations of As, Hg, Co, Cr and Cd were tested for each soil sample, and their spatial patterns were analyzed by the semivariogram approach of geostatistics and geographical information system technology. Multivariate statistic approaches (principal component analysis and cluster analysis) were used to identify heavy metal sources and their spatial pattern. Principal component analysis coupled with correlation between heavy metals showed that primary inputs of As, Hg and Cd were due to anthropogenic while, Co, and Cr were associated with pedogenic factors. Ordinary kriging was carried out to map the spatial patters of heavy metals. The high pollution sources evaluated was related with usage of urban and industrial wastewater. The results of this study helpful for risk assessment of environmental pollution for decision making for industrial adjustment and remedy soil pollution.Keywords: Geographic Information system, Geostatistics, Kaveh, Multivariate Statistical Analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19838355 Hydrochemical Contamination Profiling and Spatial-Temporal Mapping with the Support of Multivariate and Cluster Statistical Analysis
Authors: S. Barbosa, M. Pinto, J. A. Almeida, E. Carvalho, C. Diamantino
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The aim of this work was to test a methodology able to generate spatial-temporal maps that can synthesize simultaneously the trends of distinct hydrochemical indicators in an old radium-uranium tailings dam deposit. Multidimensionality reduction derived from principal component analysis and subsequent data aggregation derived from clustering analysis allow to identify distinct hydrochemical behavioral profiles and generate synthetic evolutionary hydrochemical maps.
Keywords: Contamination plume migration, K-means of PCA scores, groundwater and mine water monitoring, spatial-temporal hydrochemical trends.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6328354 Time-Domain Analysis of Pulse Parameters Effects on Crosstalk (In High Speed Circuits)
Authors: L. Tani, N. El Ouzzani
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Crosstalk among interconnects and printed-circuit board (PCB) traces is a major limiting factor of signal quality in highspeed digital and communication equipments especially when fast data buses are involved. Such a bus is considered as a planar multiconductor transmission line. This paper will demonstrate how the finite difference time domain (FDTD) method provides an exact solution of the transmission-line equations to analyze the near end and the far end crosstalk. In addition, this study makes it possible to analyze the rise time effect on the near and far end voltages of the victim conductor. The paper also discusses a statistical analysis, based upon a set of several simulations. Such analysis leads to a better understanding of the phenomenon and yields useful information.Keywords: Multiconductor transmission line, Crosstalk, Finite difference time domain (FDTD), printed-circuit board (PCB), Rise time, Statistical analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17768353 Development of Position Changing System for Obstructive Sleep Apnea Patient using HRV
Authors: Soo- Young Ye, Dong-Hyun Kim
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Obstructive sleep apnea in patients, between 70 and 80 percent, can be cured with just a posture correcting. The most import thing to do this is detection of obstructive sleep apnea. Detection of obstructive sleep apnea can be performed through heart rate variability analysis using power spectrum density analysis. After HRV analysis we needed to know the current position information for correcting the position. The pressure sensors of the array type were used to obtain position information. These sensors can obtain information from the experimenter about position. In addition, air cylinder corrected the position of the experimenter by lifting the bed. The experimenter can be changed position without breaking during sleep by the system. Polysomnograph recording were obtained from 10 patients. The results of HRV analysis were that NLF and LF/HF ratio increased, while NHF decreased during OSA. Position change had to be done the periods.Keywords: Obstructive sleep apnea, Heart rate variability, Air cylinder, PSD, RR interval, ANS
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16948352 Environmental Analysis of Springs in Urban Areas–A Methodological Proposal
Authors: Milton Pavezzi Netto, Gustavo D'Almeida Scarpinella, Ricardo Siloto da Silva
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The springs located in urban areas are the outpouring of surface water, which can serve as water supply, effluent receptors and important local macro-drainage elements. With unplanned occupation, non-compliance with environmental legislation and the importance of these water bodies, it is vital to analyze the springs within urban areas, considering the Brazilian forest code. This paper submits an analysis and discussion methodology proposal of environmental compliance functions of urban springs, by means of G.I.S. - Geographic Information System analysis - and in situ analysis. The case study included two springs which exhibit a history of occupation along its length, with different degrees of impact. The proposed method is effective and easy to apply, representing a powerful tool for analyzing the environmental conditions of springs in urban areas.Keywords: Springs, urban area, Brazilian forest code.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15968351 Seismic Performance Evaluation of Bridge Structures Using 3D Finite Element Methods in South Korea
Authors: Woo Young Jung, Bu Seog Ju
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This study described the seismic performance evaluation of bridge structures, located near Daegu metropolitan city in Korea. The structural design code or regulatory guidelines is focusing on the protection of brittle failure or collapse in bridges’ lifetime during an earthquake. This paper illustrated the procedure in terms of the safety evaluation of bridges using simple linear elastic 3D Finite Element (FE) model in ABAQUS platform. The design response spectra based on KBC 2009 were then developed, in order to understand the seismic behavior of bridge structures. Besides, the multiple directional earthquakes were applied and it revealed that the most dominated earthquake direction was transverse direction of the bridge. Also, the bridge structure under the compressive stress was more fragile than the tensile stress and the vertical direction of seismic ground motions was not significantly affected to the structural system.Keywords: Bridge, Finite Element, 3D model, Earthquake, Spectrum.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16438350 Impact Assessment of Lean Practices on Social Sustainability Indicators: An Approach Using ISM Method
Authors: Aline F. Marcon, Eduardo F. da Silva, Marina Bouzon
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The impact of lean management on environmental sustainability is the research line that receives the most attention from academicians. Therefore, the social dimension of sustainable development has so far received less attention. This paper aims to evaluate the impact of intra-plant lean manufacturing practices on social sustainability indicators extracted from the Global Reporting Initiative (GRI) parameters. The method is two-phased, including MCDM approach to uncover the most relevant practices regarding social performance and Interpretive Structural Modeling (ISM) method to reveal the structural relationship among lean practices. Professionals from the academic and industrial fields answered the questionnaires. From the results of this paper, it is possible to verify that practices such as “Safety Improvement Programs”, “Total Quality Management” and “Cross-functional Workforce” are the ones which have the most positive influence on the set of GRI social indicators.
Keywords: Indicators, ISM, lean, social, sustainability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8038349 Identifying and Prioritizing Factors Affecting Consumer Behavior Based on Product Value
Authors: Houshang Taghizadeh, Gholamreza Soltani Fesghandis
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Nowadays, without the awareness of consumer behavior and correct understanding of it, it is not possible for organizations to take appropriate measures to meet the consumer needs and demands. The aim of this paper is the identification and prioritization of the factors affecting the consumer behavior based on the product value. The population of the study includes all the consumers of furniture producing firms in East Azarbaijan province, Iran. The research sample includes 93 people selected by the sampling formula in unlimited population. The data collection instrument was a questionnaire, the validity of which was confirmed through face validity and the reliability of which was determined, using Cronbach's alpha coefficient. The Kolmogorov-Smironov test was used to test data normality, the t-test for identification of factors affecting the product value, and Friedman test for prioritizing the factors. The results show that quality, satisfaction, styling, price, finishing operation, performance, safety, worth, shape, use, and excellence are placed from 1 to 11 priorities, respectively.Keywords: Consumer Behavior, Consumer Satisfaction, Product, Value
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29068348 Aircraft Selection Using Preference Optimization Programming (POP)
Authors: C. Ardil
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A multiple-criteria decision support system is proposed for the best aircraft selection decision. Various strategic, economic, environmental, and risk-related factors can directly or indirectly influence this choice, and they should be taken into account in the decision-making process. The paper suggests a multiple-criteria analysis to aid in the airline management's decision-making process when choosing an appropriate aircraft. In terms of the suggested approach, an integrated entropic preference optimization programming (POP) for fleet modeling risk analysis is applied. The findings of the study of multiple criteria analysis indicate that the A321(neo) aircraft type is the best alternative in this particular optimization instance. The proposed methodology can be applied to other complex engineering problems involving multiple criteria analysis.
Keywords: Aircraft selection, decision making, multiple criteria decision making, preference optimization programming, POP, entropic weight method, TOPSIS, WSM, WPM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6368347 A Cost-Effective Design and Analysis of Full Bridge LLC Resonant Converter
Authors: Kaibalya Prasad Panda, Sreyasee Rout
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LLC (Inductor-inductor-capacitor) resonant converter has lots of advantages over other type of resonant converters which include high efficiency, more reliable and have high power density. This paper presents the design and analysis of a full bridge LLC resonant converter. In addition to the operational principle, the ZVS and ZCS conditions are also explained with the DC characteristics. Simulation of the LLC resonant converter is performed in MATLAB/ Simulink and the practical prototype setup is analyzed in Proteus software. The result is verified through analysis and design of a low cost, 200 watt prototype converter.
Keywords: LLC, Proteus, Resonant converter ZCS, ZVS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31098346 Analysis and Flight Test for Small Inflatable Wing Design
Authors: Zhang Jun-Tao, Hou Zhong-xi, Guo Zheng, Chen Li-li
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This article discusses stress analysis and the shape characteristics of the inflatable wing, and then introduces the design method of inflatable wing, in order to accurately approximate a standard airfoil. It specifically analyses the aerodynamic characteristics of the inflatable wing with the method of CFD, along with comparing to standard airfoil, afterwards we carries out the manufacture of inflatable wing and the flight test.
Keywords: Inflatable wing, Stress analysis, Aerodynamic characteristics, Flight test
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27028345 Studying the Effect of Froude Number and Densimetric Froude Number on Local Scours around Circular Bridge Piers
Authors: Md Abdullah Al Faruque
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A very large percentage of bridge failures are attributed to scouring around bridge piers and this directly influences public safety. Experiments are carried out in a 12-m long rectangular open channel flume made of transparent tempered glass. A 300 mm thick bed made up of sand particles is leveled horizontally to create the test bed and a 50 mm hollow plastic cylinder is used as a model bridge pier. Tests are carried out with varying flow depths and velocities. Data points of various scour parameters such as scour depth, width, and length are collected based on different flow conditions and visual observations of changes in the stream bed downstream the bridge pier are also made as the scour progresses. Result shows that all three major flow characteristics (flow depth, Froude number and densimetric Froude number) have one way or other affect the scour profile.
Keywords: Bridge pier scour, densimetric Froude number, flow depth, Froude Number, sand.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9858344 Specifying Strict Serializability of Iterated Transactions in Propositional Temporal Logic
Authors: Walter Hussak
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We present an operator for a propositional linear temporal logic over infinite schedules of iterated transactions, which, when applied to a formula, asserts that any schedule satisfying the formula is serializable. The resulting logic is suitable for specifying and verifying consistency properties of concurrent transaction management systems, that can be defined in terms of serializability, as well as other general safety and liveness properties. A strict form of serializability is used requiring that, whenever the read and write steps of a transaction occurrence precede the read and write steps of another transaction occurrence in a schedule, the first transaction must precede the second transaction in an equivalent serial schedule. This work improves on previous work in providing a propositional temporal logic with a serializability operator that is of the same PSPACE complete computational complexity as standard propositional linear temporal logic without a serializability operator.
Keywords: Temporal logic, iterated transactions, serializability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15688343 Seismic Behavior Evaluation of Semi-Rigid Steel Frames with Knee Bracing by Modal Pushover Analysis (MPA)
Authors: Farzan Namvari, Panam Zarfam
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Nowadays use of a new structural bracing system called 'Knee Bracing System' have taken the specialists attention too much. On the other hand nonlinear static analysis procedures in estimate structures performance in earthquake time have taken attention too much. One of these procedure is modal pushover analysis (MPA) procedure. The accuracy of MPA procedure for simple steel moment resisting frame has been verified and considered in Chintanapakdee and Chopra-s article in 2003. Since the accuracy of MPA procedure has not verified for semi-rigid steel frames with knee bracing, we are going to get through with this matter in this study. For this purpose, the selected structures are four frames with different heights, 5 to 20 stories, will be designed according to AISC criteria. Then MPA procedure is used for the same frames with different rigidity percentiles of connections. The results of seismic responses are compared with dynamic nonlinear response history analysis as exact procedure and accuracy of MPA procedure is evaluated. It seems that MPA procedure accuracy will come down by reduction of the rigidity percentiles of semi-rigid connections.Keywords: Knee Bracing, Modal Pushover Analysis, SeismicBehavior, Semi-Rigid Connections.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21398342 Combination of Geological, Geophysical and Reservoir Engineering Analyses in Field Development: A Case Study
Authors: Atif Zafar, Fan Haijun
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A sequence of different Reservoir Engineering methods and tools in reservoir characterization and field development are presented in this paper. The real data of Jin Gas Field of L-Basin of Pakistan is used. The basic concept behind this work is to enlighten the importance of well test analysis in a broader way (i.e. reservoir characterization and field development) unlike to just determine the permeability and skin parameters. Normally in the case of reservoir characterization we rely on well test analysis to some extent but for field development plan, the well test analysis has become a forgotten tool specifically for locations of new development wells. This paper describes the successful implementation of well test analysis in Jin Gas Field where the main uncertainties are identified during initial stage of field development when location of new development well was marked only on the basis of G&G (Geologic and Geophysical) data. The seismic interpretation could not encounter one of the boundary (fault, sub-seismic fault, heterogeneity) near the main and only producing well of Jin Gas Field whereas the results of the model from the well test analysis played a very crucial rule in order to propose the location of second well of the newly discovered field. The results from different methods of well test analysis of Jin Gas Field are also integrated with and supported by other tools of Reservoir Engineering i.e. Material Balance Method and Volumetric Method. In this way, a comprehensive way out and algorithm is obtained in order to integrate the well test analyses with Geological and Geophysical analyses for reservoir characterization and field development. On the strong basis of this working and algorithm, it was successfully evaluated that the proposed location of new development well was not justified and it must be somewhere else except South direction.Keywords: Field development, reservoir characterization, reservoir engineering, well test analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11208341 Effect of Valve Pressure Drop in Exergy Analysis of C2+ Recovery Plants Refrigeration Cycles
Authors: B. Tirandazi, M. Mehrpooya, A. Vatani
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This paper provides an exergy analysis of the multistage refrigeration cycle used for C2+ recovery plant. The behavior of an industrial refrigeration cycle with refrigerant propane has been investigated by the exergy method. A computational model based on the exergy analysis is presented for the investigation of the effects of the valves on the exergy losses, the second law of efficiency, and the coefficient of performance (COP) of a vapor compression refrigeration cycle. The equations of exergy destruction and exergetic efficiency for the main cycle components such as evaporators, condensers, compressors, and expansion valves are developed. The relations for the total exergy destruction in the cycle and the cycle exergetic efficiency are obtained. An ethane recovery unit with its refrigeration cycle has been simulated to prepare the exergy analysis. Using a typical actual work input value; the exergetic efficiency of the refrigeration cycle is determined to be 39.90% indicating a great potential for improvements. The simulation results reveal that the exergetic efficiencies of the heat exchanger and expansion sections get the lowest rank among the other compartments of refrigeration cycle. Refrigeration calculations have been carried out through the analysis of T–S and P–H diagrams where coefficient of performance (COP) was obtained as 1.85. The novelty of this article includes the effect and sensitivity analysis of molar flow, pressure drops and temperature on the exergy efficiency and coefficient of performance of the cycle.
Keywords: exergy; Valve; CRP; refrigeration cycle; propane refrigerant; C2+ Recovery; Ethane Recovery;.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12108340 Dynamic Construction Site Layout Using Ant Colony Optimization
Authors: Y. Abdelrazig
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Evolutionary optimization methods such as genetic algorithms have been used extensively for the construction site layout problem. More recently, ant colony optimization algorithms, which are evolutionary methods based on the foraging behavior of ants, have been successfully applied to benchmark combinatorial optimization problems. This paper proposes a formulation of the site layout problem in terms of a sequencing problem that is suitable for solution using an ant colony optimization algorithm. In the construction industry, site layout is a very important planning problem. The objective of site layout is to position temporary facilities both geographically and at the correct time such that the construction work can be performed satisfactorily with minimal costs and improved safety and working environment. During the last decade, evolutionary methods such as genetic algorithms have been used extensively for the construction site layout problem. This paper proposes an ant colony optimization model for construction site layout. A simple case study for a highway project is utilized to illustrate the application of the model.Keywords: Construction site layout, optimization, ant colony.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31298339 Comparison of Newton Raphson and Gauss Seidel Methods for Power Flow Analysis
Authors: H. Abaali, T. Talbi, R.Skouri
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This paper presents a comparative study of the Gauss Seidel and Newton-Raphson polar coordinates methods for power flow analysis. The effectiveness of these methods are evaluated and tested through a different IEEE bus test system on the basis of number of iteration, computational time, tolerance value and convergence.
Keywords: Convergence time, Gauss-Seidel Method, Newton-Raphson Method, number of iteration, power flow analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2552