Search results for: site response
1619 Response Surface Based Optimization of Toughness of Hybrid Polyamide 6 Nanocomposites
Authors: E. Hajizadeh, H. Garmabi
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Toughening of polyamide 6 (PA6)/ Nanoclay (NC) nanocomposites with styrene-ethylene/butadiene-styrene copolymer (SEBS) using maleated styrene-ethylene/butadiene-styrene copolymer (mSEBS)/ as a compatibilizer were investigated by blending them in a co-rotating twin-screw extruder. Response surface method of experimental design was used for optimizing the material and processing parameters. Effect of four factors, including SEBS, mSEBS and NC contents as material variables and order of mixing as a processing factor, on toughness of hybrid nanocomposites were studied. All the prepared samples showed ductile behavior and low temperature Izod impact toughness of some of the hybrid nanocomposites demonstrated 900% improvement compared to the PA6 matrix while the modulus showed maximum enhancement of 20% compared to the pristine PA6 resin.
Keywords: Hybrid nanocomposites, PA6, SEBS rubber, toughness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16251618 Multi-criteria Optimization of Square Beam using Linear Weighted Average Model
Authors: Ali Farhaninejad, Rizal Zahari, Ehsan Rasooliyazdi
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Increasing energy absorption is a significant parameter in vehicle design. Absorbing more energy results in decreasing occupant damage. Limitation of the deflection in a side impact results in decreased energy absorption (SEA) and increased peak load (PL). Hence a high crash force jeopardizes passenger safety and vehicle integrity. The aims of this paper are to determine suitable dimensions and material of a square beam subjected to side impact, in order to maximize SEA and minimize PL. To achieve this novel goal, the geometric parameters of a square beam are optimized using the response surface method (RSM).multi-objective optimization is performed, and the optimum design for different response features is obtained.Keywords: Crashworthiness, side impact, energy absorption, multi-objective optimization, Square beam, SEA
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18341617 Analysis of a Coupled Hydro-Sedimentological Numerical Model for the Tombolo of GIENS
Authors: Yves Lacroix, Van Van Than, Didier Leandri, Pierre Liardet
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The western Tombolo of the Giens peninsula in southern France, known as Almanarre beach, is subject to coastal erosion. We are trying to use computer simulation in order to propose solutions to stop this erosion. Our aim was first to determine the main factors for this erosion and successfully apply a coupled hydrosedimentological numerical model based on observations and measurements that have been performed on the site for decades. We have gathered all available information and data about waves, winds, currents, tides, bathymetry, coastal line, and sediments concerning the site. These have been divided into two sets: one devoted to calibrating a numerical model using Mike 21 software, the other to serve as a reference in order to numerically compare the present situation to what it could be if we implemented different types of underwater constructions. This paper presents the first part of the study: selecting and melting different sources into a coherent data basis, identifying the main erosion factors, and calibrating the coupled software model against the selected reference period. Our results bring calibration of the numerical model with good fitting coefficients. They also show that the winter South-Western storm events conjugated to depressive weather conditions constitute a major factor of erosion, mainly due to wave impact in the northern part of the Almanarre beach. Together, current and wind impact is shown negligible.
Keywords: Almanarre beach, coastal erosion, hydro-sedimentological, numerical model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20421616 DEA-Based Variable Structure Position Control of DC Servo Motor
Authors: Ladan Maijama’a, Jibril D. Jiya, Ejike C. Anene
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This paper presents Differential Evolution Algorithm (DEA) based Variable Structure Position Control (VSPC) of Laboratory DC servomotor (LDCSM). DEA is employed for the optimal tuning of Variable Structure Control (VSC) parameters for position control of a DC servomotor. The VSC combines the techniques of Sliding Mode Control (SMC) that gives the advantages of small overshoot, improved step response characteristics, faster dynamic response and adaptability to plant parameter variations, suppressed influences of disturbances and uncertainties in system behavior. The results of the simulation responses of the VSC parameters adjustment by DEA were performed in Matlab Version 2010a platform and yield better dynamic performance compared with the untuned VSC designed.Keywords: Differential evolution algorithm, laboratory DC servomotor, sliding mode control, variable structure control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15651615 Verification and Proposal of Information Processing Model Using EEG-Based Brain Activity Monitoring
Authors: Toshitaka Higashino, Naoki Wakamiya
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Human beings perform a task by perceiving information from outside, recognizing them, and responding them. There have been various attempts to analyze and understand internal processes behind the reaction to a given stimulus by conducting psychological experiments and analysis from multiple perspectives. Among these, we focused on Model Human Processor (MHP). However, it was built based on psychological experiments and thus the relation with brain activity was unclear so far. To verify the validity of the MHP and propose our model from a viewpoint of neuroscience, EEG (Electroencephalography) measurements are performed during experiments in this study. More specifically, first, experiments were conducted where Latin alphabet characters were used as visual stimuli. In addition to response time, ERPs (event-related potentials) such as N100 and P300 were measured by using EEG. By comparing cycle time predicted by the MHP and latency of ERPs, it was found that N100, related to perception of stimuli, appeared at the end of the perceptual processor. Furthermore, by conducting an additional experiment, it was revealed that P300, related to decision making, appeared during the response decision process, not at the end. Second, by experiments using Japanese Hiragana characters, i.e. Japan's own phonetic symbols, those findings were confirmed. Finally, Japanese Kanji characters were used as more complicated visual stimuli. A Kanji character usually has several readings and several meanings. Despite the difference, a reading-related task and a meaning-related task exhibited similar results, meaning that they involved similar information processing processes of the brain. Based on those results, our model was proposed which reflects response time and ERP latency. It consists of three processors: the perception processor from an input of a stimulus to appearance of N100, the cognitive processor from N100 to P300, and the decision-action processor from P300 to response. Using our model, an application system which reflects brain activity can be established.
Keywords: Brain activity, EEG, information processing model, model human processor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6911614 Real Time Monitoring of Long Slender Shaft by Distributed-Lumped Modeling Techniques
Authors: Sina Babadi, K. M. Ebrahimi
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The aim of this paper is to determine the stress levels at the end of a long slender shaft such as a drilling assembly used in the oil or gas industry using a mathematical model in real-time. The torsional deflection experienced by this type of drilling shaft (about 4 KM length and 20 cm diameter hollow shaft with a thickness of 1 cm) can only be determined using a distributed modeling technique. The main objective of this project is to calculate angular velocity and torque at the end of the shaft by TLM method and also analyzing of the behavior of the system by transient response. The obtained result is compared with lumped modeling technique the importance of these results will be evident only after the mentioned comparison. Two systems have different transient responses and in this project because of the length of the shaft transient response is very important.Keywords: Distributed Lumped modeling, Lumped modeling, Drill string, Angular Velocity, Torque.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14611613 How the Decrease of Collagen or Mineral Affect the Fracture in the Turkey Long Bones
Authors: P. Vosynek, T. Návrat, M. Peč, J. Pořízka, P. Diviš
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Bone properties and response behavior after static or dynamic activation (loading) are still interesting topics in many fields of the science especially in the biomechanical problems such as bone loss of astronauts in space, osteoporosis, bone remodeling after fracture or remodeling after surgery (endoprosthesis and implants) and in osteointegration. This contribution deals with the relation between physiological, demineralized and deproteinized state of the turkey long bone – tibia. Three methods for comparison were used: 1) densitometry, 2) three point bending and 3) frequency analysis. The main goal of this work was to describe the decrease of the protein (collagen) or mineral of the bone with relation to the fracture in three point bending. The comparison is linked to the problem of different bone mechanical behavior in physiological and osteoporotic state.
Keywords: Bone properties, long bone, osteoporosis, response behavior.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22761612 Transient Stress Analysis on Medium Modules Spur Gear by Using Mode Super Position Technique
Authors: Ali Raad Hassan
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Natural frequencies and dynamic response of a spur gear sector are investigated using a two dimensional finite element model that offers significant advantages for dynamic gear analyses. The gear teeth are analyzed for different operating speeds. A primary feature of this modeling is determination of mesh forces using a detailed contact analysis for each time step as the gears roll through the mesh. ANSYS software has been used on the proposed model to find the natural frequencies by Block Lanczos technique and displacements and dynamic stresses by transient mode super position method. The effect of rotational speed of the gear on the dynamic response of gear tooth has been studied and design limits have been discussed.Keywords: Spur gear, Natural frequency, transient analysis, Mode super position technique.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29821611 SMRF Seismic Response: Unequal Beam Depths
Authors: Babak H. Mamamqani, Alimohammad Entezarmahdi
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There are many researches on parameters affecting seismic behavior of steel moment frames. Great deal of these researches considers cover plate connections with or without haunch and direct beam to column connection for exterior columns. Also there are experimental results for interior connections with equal beam depth on both sides but not much research has been performed on the seismic behavior of joints with unequal beam depth. Based on previous experimental results, a series of companion analyses have been set up considering different beam height and connection detailing configuration to investigate the seismic behavior of the connections. Results of this study indicate that when the differences between beams height on both side increases, use of haunch connection system leads to significant improvement in the seismic response whereas other configurations did not provide satisfying results.
Keywords: Analytical modeling, Haunch connection, Seismic design, Unequal beam depth.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27811610 Analytical Prediction of Seismic Response of Steel Frames with Superelastic Shape Memory Alloy
Authors: Mohamed Omar
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Superelastic Shape Memory Alloy (SMA) is accepted when it used as connection in steel structures. The seismic behaviour of steel frames with SMA is being assessed in this study. Three eightstorey steel frames with different SMA systems are suggested, the first one of which is braced with diagonal bracing system, the second one is braced with nee bracing system while the last one is which the SMA is used as connection at the plastic hinge regions of beams. Nonlinear time history analyses of steel frames with SMA subjected to two different ground motion records have been performed using Seismostruct software. To evaluate the efficiency of suggested systems, the dynamic responses of the frames were compared. From the comparison results, it can be concluded that using SMA element is an effective way to improve the dynamic response of structures subjected to earthquake excitations. Implementing the SMA braces can lead to a reduction in residual roof displacement. The shape memory alloy is effective in reducing the maximum displacement at the frame top and it provides a large elastic deformation range. SMA connections are very effective in dissipating energy and reducing the total input energy of the whole frame under severe seismic ground motion. Using of the SMA connection system is more effective in controlling the reaction forces at the base frame than other bracing systems. Using SMA as bracing is more effective in reducing the displacements. The efficiency of SMA is dependant on the input wave motions and the construction system as well.Keywords: Finite element analysis, seismic response, shapesmemory alloy, steel frame, superelasticity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18451609 Advanced ILQ Control for Buck-Converter viaTwo-Degrees of Freedom Servo-System
Authors: Sidshchadhaa Aumted, Shuhei Shiina, Hiroshi Takami
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In this paper, we propose an advanced ILQ control for the buck-converter via two-degrees of freedom servo-system. Our presented strategy is based on Inverse Linear Quadratic (ILQ) servo-system controller without solving Riccati-s equation directly. The optimal controller of the current and voltage control system is designed. The stability and robust control are analyzed. A conscious and persistent effort has been made to improve ILQ control via two-degrees of freedom guarantees the optimal gains on the basis of polynomial pole assignment, which our results of the proposed strategy shows that the advanced ILQ control can be controlled independently the step response and the disturbance response by appending a feed-forward compensator.
Keywords: Optimal voltage control, inverse LQ design method, second order polynomial, two-degrees of freedom.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19811608 Identifying Dynamic Structural Parameters of Soil-Structure System Based on Data Recorded during Strong Earthquakes
Authors: Vahidreza Mahmoudabadi, Omid Bahar, Mohammad Kazem Jafari
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In many applied engineering problems, structural analysis is usually conducted by assuming a rigid bed, while imposing the effect of structure bed flexibility can affect significantly on the structure response. This article focuses on investigation and evaluation of the effects arising from considering a soil-structure system in evaluation of dynamic characteristics of a steel structure with respect to elastic and inelastic behaviors. The recorded structure acceleration during Taiwan’s strong Chi-Chi earthquake on different floors of the structure was our evaluation criteria. The respective structure is an eight-story steel bending frame structure designed using a displacement-based direct method assuring weak beam - strong column function. The results indicated that different identification methods i.e. reverse Fourier transform or transfer functions, is capable to determine some of the dynamic parameters of the structure precisely, rather than evaluating all of them at once (mode frequencies, mode shapes, structure damping, structure rigidity, etc.). Response evaluation based on the input and output data elucidated that the structure first mode is not significantly affected, even considering the soil-structure interaction effect, but the upper modes have been changed. Also, it was found that the response transfer function of the different stories, in which plastic hinges have occurred in the structure components, provides similar results.
Keywords: System identification, dynamic characteristics, soil-structure system, bending steel frame structure, displacement-based design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9511607 Nonlinear Response of Infinite Beams on a Tensionless Extensible Geosynthetic – Reinforced Earth Beds under Moving Load
Authors: Karuppsamy K., Eswara Prasad C. R.
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In this paper analysis of an infinite beam resting on tensionless extensible geosynthetic reinforced granular bed overlying soft soil strata under moving load with constant velocity is presented. The beam is subjected to a concentrated load moving with constant velocity. The upper reinforced granular bed is modeled by a rough elastic membrane embedded in Pasternak shear layer overlying a series of compressible nonlinear Winkler springs representing the under-lied very poor soil. The tensionless extensible geosynthetic layer has been assumed to deform such that at interface the geosynthetic and the soil have some deformation. Nonlinear behavior of granular fill and the very poor soil has been considered in the analysis by means of hyperbolic constitutive relationships. Detailed parametric study has been conducted to study the influence of various parameters on the response of soil foundation system under consideration by means of deflection and bending moment in the beam and tension mobilized in the geosynthetic layer. This study clearly observed that the comparisons of tension and tensionless foundation and magnitude of applied load, relative compressibility of granular fill and ultimate resistance of poor soil has significant influence on the response of soil foundation system.
Keywords: Infinite Beams, Tensionless Extensible Geosynthetic, Granular layer, Moving Load and Nonlinear behavior of poor soil
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20481606 Pushover Analysis of Reinforced Concrete Buildings Using Full Jacket Technics: A Case Study on an Existing Old Building in Madinah
Authors: Tarek M. Alguhane, Ayman H. Khalil, M. N. Fayed, Ayman M. Ismail
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The retrofitting of existing buildings to resist the seismic loads is very important to avoid losing lives or financial disasters. The aim at retrofitting processes is increasing total structure strength by increasing stiffness or ductility ratio. In addition, the response modification factors (R) have to satisfy the code requirements for suggested retrofitting types. In this study, two types of jackets are used, i.e. full reinforced concrete jackets and surrounding steel plate jackets. The study is carried out on an existing building in Madinah by performing static pushover analysis before and after retrofitting the columns. The selected model building represents nearly all-typical structure lacks structure built before 30 years ago in Madina City, KSA. The comparison of the results indicates a good enhancement of the structure respect to the applied seismic forces. Also, the response modification factor of the RC building is evaluated for the studied cases before and after retrofitting. The design of all vertical elements (columns) is given. The results show that the design of retrofitted columns satisfied the code's design stress requirements. However, for some retrofitting types, the ductility requirements represented by response modification factor do not satisfy KSA design code (SBC- 301).Keywords: Concrete jackets, steel jackets, RC buildings pushover analysis, non-linear analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17791605 Transformer Diagnosis Based on Coupled Circuits Method Modelling
Authors: Labar Hocine, Rekik Badri, Bounaya Kamel, Kelaiaia Mounia Samira
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Diagnostic goal of transformers in service is to detect the winding or the core in fault. Transformers are valuable equipment which makes a major contribution to the supply security of a power system. Consequently, it is of great importance to minimize the frequency and duration of unwanted outages of power transformers. So, Frequency Response Analysis (FRA) is found to be a useful tool for reliable detection of incipient mechanical fault in a transformer, by finding winding or core defects. The authors propose as first part of this article, the coupled circuits method, because, it gives most possible exhaustive modelling of transformers. And as second part of this work, the application of FRA in low frequency in order to improve and simplify the response reading. This study can be useful as a base data for the other transformers of the same categories intended for distribution grid.
Keywords: Diagnostic, Coupled Circuit Method, FRA, Transformer Faults
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15211604 Three Dimensional Dynamic Analysis of Water Storage Tanks Considering FSI Using FEM
Authors: S. Mahdi S. Kolbadi, Ramezan Ali Alvand, Afrasiab Mirzaei
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In this study, to investigate and analyze the seismic behavior of concrete in open rectangular water storage tanks in two-dimensional and three-dimensional spaces, the Finite Element Method has been used. Through this method, dynamic responses can be investigated together in fluid storages system. Soil behavior has been simulated using tanks boundary conditions in linear form. In this research, in addition to flexibility of wall, the effects of fluid-structure interaction on seismic response of tanks have been investigated to account for the effects of flexible foundation in linear boundary conditions form, and a dynamic response of rectangular tanks in two-dimensional and three-dimensional spaces using finite element method has been provided. The boundary conditions of both rigid and flexible walls in two-dimensional finite element method have been considered to investigate the effect of wall flexibility on seismic response of fluid and storage system. Furthermore, three-dimensional model of fluid-structure interaction issue together with wall flexibility has been analyzed under the three components of earthquake. The obtained results show that two-dimensional model is also accurately near to the results of three-dimension as well as flexibility of foundation leads to absorb received energy and relative reduction of responses.
Keywords: Dynamic behavior, water storage tank, fluid-structure interaction, flexible wall.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9821603 Biomass and Productivity Studies of Up-Land and Low-Land Vegetation in the Neglected Margin of a Tropical Lake
Authors: Mayank Singh, O. P. Singh ‘Vatsa’, M. P. Singh
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Present paper deals with an evaluation of magnitude of changes in biomass and net primary productivity at ‘Gujar Tal’ sloppy lake margin at Jaunpur in tropical semi-arid region of eastern U.P. (India). The study site abandoned or neglected lands (50 ×125 m) was divided into two zones, i.e. upper zone (up-land) and lower zone (low-land). Maximum biomass in the upper zone of dominant weed Desmostachya bipinnata (L.) Stapf. was 207.47 g m-2 and ‘rest weeds’ was 457.45 g m-2 both in the month of September. In contrast, the peak biomass value in the lower zone of dominant weed Oryza rufipogon Griff. was 1571.44 g m-2 in October and ‘rest weeds’ 270.65 g m-2 in February. Among the two zones, the peak total community biomass was observed 1655.62 g m-2 (October) in the lower zone while its peak value for the upper zone 457.45 g m-2 (September) was comparatively low. Maximum percentage contribution of dominant weeds (D. bipinnata and O. rufipogon) in the respective upper and lower zones and ‘rest weeds’ in both the zones varied in different months in the total community biomass. The peak net primary productivity of dominant weed (D. bipinnata) was 2.09g m-2 day-1 (September) and ‘rest weeds’ was 2.37 g m-2 day-1 (August) in the upper zone, while the lower zone for O. rufipogon was 5.25 g m-2 day-1 (June) as this zone was inundated later and ‘rest weeds’ was 2.08 g m-2 day-1 (January, 2009). The annual net production of total community at site I was highest, 409.58 g m-2 yr-1 in the upper zone followed by 395.58 g m-2 per eight month in the lower zone as this zone was flooded with water during rainy season. The site significance of variations in biomass in relation to plant species was tested by analysis of variance. It was significant between months in all the two zones (p<0.01 and p<0.05).
Keywords: Biomass, Neglected Lake Margin, Productivity, Vegetation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17281602 Development and Acceptance of a Proposed Module for Enhancing the Reading and Writing Skills in Baybayin: The Traditional Writing System in the Philippines
Authors: Maria Venus G. Solares
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The ancient Filipinos had their own spelling or alphabet that differed from the modern Roman alphabet brought by the Spaniards. It consists of seventeen letters, three vowels, and fourteen consonants and is called Baybayin. The Baybayin, a traditional writing system, is composed of characters that represent syllables. A proposal in the Philippine Congress to declare Baybayin as the national writing system inspired this study. The main objective of this study was to develop and assess the proposed module for enhancing the reading and writing skills in Baybayin of the students. The aim was to ensure the acceptability of the Baybayin using the proposed module and to meet the needs of students in developing their ability to read and write Baybayin through the module. A quasi-experimental research design was used in this study. The data were collected through the initial and final analysis of the students of Adamson University's ABM 1102 using convenient sampling techniques. Based on statistical analysis of data using weighted mean, standard deviation, and paired t-tests, the proposed module helped improve the students' literacy skills, and the response exercises in the proposed module changed the acceptability of the Baybayin in their minds. The study showed that there was an important difference in the scores of students before and after the use of the module. The students' response to the assessment of their reading and writing skills on Baybayin was highly acceptable. This study will help to develop the reading and writing skills of the students in Baybayin and to teach the Baybayin in response to the revival of a part of Philippine culture that has been long forgotten.
Keywords: Baybayin, proposed module, ancient writing, acceptability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 511601 Energy Efficient Construction and the Seismic Resistance of Passive Houses
Authors: Vojko Kilar, Boris Azinović, David Koren
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Recently, an increasing trend of passive and low-energy buildings transferring form non earthquake-prone to earthquake-prone regions has thrown out the question about the seismic safety of such buildings. The paper describes the most commonly used thermal insulating materials and the special details, which could be critical from the point of view of earthquake resistance. The most critical appeared to be the cases of buildings founded on the RC foundation slab lying on a thermal insulation (TI) layer made of extruded polystyrene (XPS). It was pointed out that in such cases the seismic response of such buildings might differ to response of their fixed based counterparts. The main parameters that need special designers’ attention are: the building’s lateral top displacement, the ductility demand of the superstructure, the foundation friction coefficient demand, the maximum compressive stress in the TI layer and the percentage of the uplifted foundation. The analyses have shown that the potentially negative influences of inserting the TI under the foundation slab could be expected only for slender high-rise buildings subjected to severe earthquakes. Oppositely it was demonstrated for the foundation friction coefficient demand which could exceed the capacity value yet in the case of low-rise buildings subjected to moderate earthquakes. Some suggestions to prevent the horizontal shifts are also given.
Keywords: Earthquake Response, Extruded Polystyrene (XPS), Low-Energy Buildings, Foundations on Thermal Insulation Layer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29981600 The Analysis of TRACE/PARCS in the Simulation of Ultimate Response Guideline for Lungmen ABWR
Authors: J. R. Wang, W.Y. Li, H.T. Lin, B.H. Lee, C. Shih, S.W. Chen
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In this research, the TRACE/PARCS model of Lungmen ABWR has been developed for verification of ultimate response guideline (URG) efficiency. This ultimate measure was named as DIVing plan, abbreviated from system depressurization, water injection and containment venting. The simulation initial condition is 100% rated power/100% rated core flow. This research focuses on the estimation of the time when the fuel might be damaged with no water injection by using TRACE/PARCS first. Then, the effect of the reactor core isolation system (RCIC), control depressurization and ac-independent water addition system (ACIWA), which can provide the injection with 950 gpm are also estimated for the station blackout (SBO) transient.
Keywords: ABWR, TRACE, safety analysis, PARCS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22221599 Nonlinear Dynamics of Cracked RC Beams under Harmonic Excitation
Authors: Atul Krishna Banik
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Nonlinear response behaviour of a cracked RC beam under harmonic excitation is analysed to investigate various instability phenomena like, bifurcation, jump phenomena etc. The nonlinearity of the system arises due to opening and closing of the cracks in the RC beam and is modelled as a cubic polynomial. In order to trace different branches at the bifurcation point on the response curve (amplitude versus frequency of excitation plot), an arc length continuation technique along with the incremental harmonic balance (IHBC) method is employed. The stability of the solution is investigated by the Floquet theory using Hsu-s scheme. The periodic solutions obtained by the IHBC method are compared with these obtained by the numerical integration of the equation of motion. Characteristics of solutions fold bifurcation, jump phenomena and from stable to unstable zones are identified.
Keywords: Incremental harmonic balance, arc-length continuation, bifurcation, jump phenomena.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15221598 Non-Burn Treatment of Health Care Risk Waste
Authors: Jefrey Pilusa, Tumisang Seodigeng
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This research discusses a South African case study for the potential of utilizing refuse-derived fuel (RDF) obtained from non-burn treatment of health care risk waste (HCRW) as potential feedstock for green energy production. This specific waste stream can be destroyed via non-burn treatment technology involving high-speed mechanical shredding followed by steam or chemical injection to disinfect the final product. The RDF obtained from this process is characterised by a low moisture, low ash, and high calorific value which means it can be potentially used as high-value solid fuel. Due to the raw feed of this RDF being classified as hazardous, the final RDF has been reported to be non-infectious and can blend with other combustible wastes such as rubber and plastic for waste to energy applications. This study evaluated non-burn treatment technology as a possible solution for on-site destruction of HCRW in South African private and public health care centres. Waste generation quantities were estimated based on the number of registered patient beds, theoretical bed occupancy. Time and motion study was conducted to evaluate the logistics viability of on-site treatment. Non-burn treatment technology for HCRW is a promising option for South Africa, and successful implementation of this method depends upon the initial capital investment, operational cost and environmental permitting of such technology; there are other influencing factors such as the size of the waste stream, product off-take price as well as product demand.
Keywords: Autoclave, disposal, fuel, incineration, medical waste.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11651597 Fuzzy Logic and Control Strategies on a Sump
Authors: Nasser Mohamed Ramli, Nurul Izzati Zulkifli
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Sump can be defined as a reservoir which contains slurry; a mixture of solid and liquid or water, in it. Sump system is an unsteady process owing to the level response. Sump level shall be monitored carefully by using a good controller to avoid overflow. The current conventional controllers would not be able to solve problems with large time delay and nonlinearities, Fuzzy Logic controller is tested to prove its ability in solving the listed problems of slurry sump. Therefore, in order to justify the effectiveness and reliability of these controllers, simulation of the sump system was created by using MATLAB and the results were compared. According to the result obtained, instead of Proportional-Integral (PI) and Proportional-Integral and Derivative (PID), Fuzzy Logic controller showed the best result by offering quick response of 0.32 s for step input and 5 s for pulse generator, by producing small Integral Absolute Error (IAE) values that are 0.66 and 0.36 respectively.
Keywords: Fuzzy, sump, level, controller.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7821596 Study of Icons in Enterprise Application Software Context
Authors: Shiva Subhedar, Abhishek Jain, Shivin Mittal
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Icons are not merely decorative elements in enterprise applications but very often used because of their many advantages such as compactness, visual appeal, etc. Despite these potential advantages, icons often cause usability problems when they are designed without consideration for their many potential downsides. The aim of the current study was to examine the effect of articulatory distance – the distance between the physical appearance of an interface element and what it actually means. In other words, will the subject find the association of the function and its appearance on the interface natural or is the icon difficult for them to associate with its function. We have calculated response time and quality of identification by varying icon concreteness, the context of usage and subject experience in the enterprise context. The subjects were asked to associate icons (prepared for study purpose) with given function options in context and out of context mode. Response time and their selection were recorded for analysis.Keywords: Icons, icon concreteness, icon recognition, HCI.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13391595 Determination of Sequential Best Replies in N-player Games by Genetic Algorithms
Authors: Mattheos K. Protopapas, Elias B. Kosmatopoulos
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An iterative algorithm is proposed and tested in Cournot Game models, which is based on the convergence of sequential best responses and the utilization of a genetic algorithm for determining each player-s best response to a given strategy profile of its opponents. An extra outer loop is used, to address the problem of finite accuracy, which is inherent in genetic algorithms, since the set of feasible values in such an algorithm is finite. The algorithm is tested in five Cournot models, three of which have convergent best replies sequence, one with divergent sequential best replies and one with “local NE traps"[14], where classical local search algorithms fail to identify the Nash Equilibrium. After a series of simulations, we conclude that the algorithm proposed converges to the Nash Equilibrium, with any level of accuracy needed, in all but the case where the sequential best replies process diverges.
Keywords: Best response, Cournot oligopoly, genetic algorithms, Nash equilibrium.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14441594 A Novel Dosimetry System for Computed Tomography using Phototransistor
Authors: C. M. M. Paschoal, M. L. Sobrinho, D. do N. Souza, J. Antônio Filho, L. A. P. Santos
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Computed tomography (CT) dosimetry normally uses an ionization chamber 100 mm long to estimate the computed tomography dose index (CTDI), however some reports have already indicated that small devices could replace the long ion chamber to improve quality assurance procedures in CT dosimetry. This paper presents a novel dosimetry system based in a commercial phototransistor evaluated for CT dosimetry. Three detector configurations were developed for this system: with a single, two and four devices. Dose profile measurements were obtained with them and their angular response were evaluated. The results showed that the novel dosimetry system with the phototransistor could be an alternative for CT dosimetry. It allows to obtain the CT dose profile in details and also to estimate the CTDI in longer length than the 100 mm pencil chamber. The angular response showed that the one device detector configuration is the most adequate among the three configurations analyzed in this study.Keywords: Computed tomography, dosimetry, photo-transistor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18671593 Application of Soft Systems Methodology in Solving Disaster Emergency Logistics Problems
Authors: Alhasan Hakami, Arun Kumar, Sung J Shim, Yousef Abu Nahleh
Abstract:
In recent years, many high intensity earthquakes have occurred around the world, such as the 2011 earthquake in Tohoku, Japan. These large-scale disasters caused huge casualties and losses. In addition, inefficient disaster response operations also caused the second wave of casualties and losses, and expanded the damage. Effective disaster management can be used to respond to the chaotic situation, and reduce the damage; however, some inefficient disaster response operations are still used. Therefore, this case study chose the 921 earthquake for analyzing disaster emergency logistics problems and proposed the Soft Systems Methodology (SSM) to solve disaster emergency logistics problems. Moreover, it analyses the effect of human factors on system operation, and suggests a solution to improve the system.
Keywords: Soft systems methodology, emergency logistics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30131592 Feasibility Study for a Castor oil Extraction Plant in South Africa
Authors: Mohamed Belaid, Edison Muzenda, Getrude Mitilene, Mansoor Mollagee
Abstract:
A feasibility study for the design and construction of a pilot plant for the extraction of castor oil in South Africa was conducted. The study emphasized the four critical aspects of project feasibility analysis, namely technical, financial, market and managerial aspects. The technical aspect involved research on existing oil extraction technologies, namely: mechanical pressing and solvent extraction, as well as assessment of the proposed production site for both short and long term viability of the project. The site is on the outskirts of Nkomazi village in the Mpumalanga province, where connections for water and electricity are currently underway, potential raw material supply proves to be reliable since the province is known for its commercial farming. The managerial aspect was evaluated based on the fact that the current producer of castor oil will be fully involved in the project while receiving training and technical assistance from Sasol Technology, the TSC and SEDA. Market and financial aspects were evaluated and the project was considered financially viable with a Net Present Value (NPV) of R2 731 687 and an Internal Rate of Return (IRR) of 18% at an annual interest rate of 10.5%. The payback time is 6years for analysis over the first 10 years with a net income of R1 971 000 in the first year. The project was thus found to be feasible with high chance of success while contributing to socio-economic development. It was recommended for lab tests to be conducted to establish process kinetics that would be used in the initial design of the plant.Keywords: Mechanical pressing, Net Present Value, Oilextraction, Project feasibility, Solvent extraction
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 60821591 Static Response of Homogeneous Clay Stratum to Imposed Structural Loads
Authors: Aaron Aboshio
Abstract:
Numerical study of the static response of homogeneous clay stratum considering a wide range of cohesion and subject to foundation loads is presented. The linear elastic–perfectly plastic constitutive relation with the von Mises yield criterion were utilised to develop a numerically cost effective finite element model for the soil while imposing a rigid body constrain to the foundation footing. From the analyses carried out, estimate of the bearing capacity factor, Nc as well as the ultimate load-carrying capacities of these soils, effect of cohesion on foundation settlements, stress fields and failure propagation were obtained. These are consistent with other findings in the literature and hence can be a useful guide in design of safe foundations in clay soils for buildings and other structure.Keywords: Bearing capacity factors, finite element method, safe bearing pressure, structure-soil interaction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19991590 Numerical Investigation on the Progressive Collapse Resistance of an RC Building with Brick Infills under Column Loss
Authors: Meng-Hao Tsai, Tsuei-Chiang Huang
Abstract:
Interior brick-infill partitions are usually considered as non-structural components and only their weight is accounted for in practical structural design. In this study, their effect on the progressive collapse resistance of an RC building subjected to sudden column loss is investigated. Three notional column loss conditions with four different brick-infill locations are considered. Column-loss response analyses of the RC building with and without brick infills are carried out. Analysis results indicate that the collapse resistance is only slightly influenced by the brick infills due to their brittle failure characteristic. Even so, they may help to reduce the inelastic displacement response under column loss. For practical engineering, it is reasonably conservative to only consider the weight of brick-infill partitions in the structural analysis.Keywords: Progressive collapse, column loss, brick-infill partition, compression strut.
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