Search results for: Core area
2890 An Exact MCNP Modeling of Pebble Bed Reactors
Authors: Amin Abedi, Naser Vosoughi, Mohammad Bagher Ghofrani
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Double heterogeneity of randomly located pebbles in the core and Coated Fuel Particles (CFPs) in the pebbles are specific features in pebble bed reactors and usually, because of difficulty to model with MCNP code capabilities, are neglected. In this study, characteristics of HTR-10, Tsinghua University research reactor, are used and not only double heterogeneous but also truncated CFPs and Pebbles are considered.Firstly, 8335 CFPs are distributed randomly in a pebble and then the core of reactor is filled with those pebbles and graphite pebbles as moderator such that 57:43 ratio of fuel and moderator pebbles is established.Finally, four different core configurations are modeled. They are Simple Cubic (SC) structure with truncated pebbles,SC structure without truncated pebble, and Simple Hexagonal(SH) structure without truncated pebbles and SH structure with truncated pebbles. Results like effective multiplication factor (Keff), critical height,etc. are compared with available data.Keywords: Double Heterogeneity, HTR-10, MCNP, Pebble Bed Reactor, Stochastic Geometry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28552889 Meaningful General Education Reform: Integrating Core Curricula and Institutional Values
Authors: Michael W. Markowitz
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A central element of higher education today is the “core” or “general education” curriculum: that configuration of courses that often encompasses the essence of liberal arts education. Ensuring that such offerings reflect the mission and values of the institution is a challenge faced by most college and universities, often more than once. This paper presents an action model of program planning designed to structure the processes of developing, implementing and revising core curricula in a manner consistent with key institutional goals and objectives. Through presentation of a case study from a university in the United States, the elements of needs assessment, stakeholder investment and collaborative compromise are shown as key components of a planning strategy that can produce a general education program that is comprehensive, academically rigorous, assessable, and mission consistent. The paper concludes with recommendations for both the implementation and evaluation of such programs in practice.Keywords: Academic assessment, academic program planning, curriculum development, general education reform.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12702888 Cuban Shelf Results of Exploration and Petroleum Potential
Authors: Vasilii V. Ananev
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Oil-and-gas potential of Cuba is found through the discoveries among which there are the most large-scale deposits, such as the Boca de Jaruco and Varadero fields of heavy oils. Currently, the petroleum and petroleum products needs of the island state are satisfied by own sources by less than a half. The prospects of the hydrocarbon resource base development are connected with the adjacent water area of the Gulf of Mexico where foreign companies had been granted license blocks for geological study and further development since 2001. Two Russian companies - JSC Gazprom Neft and OJSC Zarubezhneft, among others, took part in the development of the Cuban part of the Gulf of Mexico. Since 2004, five oil wells have been drilled by various companies in the deep waters of the exclusive economic zone of Cuba. Commercial oil-and-gas bearing prospects have been established in neither of them for both geological and technological reasons. However, only a small part of the water area has been covered by drilling and the productivity of the drill core has been tested at the depth of Cretaceous sediments only. In our opinion, oil-and-gas bearing prospects of the exclusive economic zone of the Republic of Cuba in the Gulf of Mexico remain undervalued and the mentioned water area needs additional geological exploration. The planning of exploration work in this poorly explored region shall be carried out systematically and it shall be based on the results of the regional scientific research.
Keywords: Cuba, Catoche, geology, exploration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13902887 Banking Union: A New Step towards Completing the Economic and Monetary Union
Authors: Marijana Ivanov, Roman Šubić
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This study analyzes the critical gaps in the architecture of European stability and the expected role of the banking union as the new important step towards completing the Economic and Monetary Union that should enable the creation of safe and sound financial sector for the euro area market. The single rulebook together with the Single Supervisory Mechanism and the Single Resolution Mechanism - as two main pillars of the banking union, should provide a consistent application of common rules and administrative standards for supervision, recovery and resolution of banks – with the final aim of replacing the former bail-out practice with the bail-in system through which possible future bank failures would be resolved by their own funds, i.e. with minimal costs for taxpayers and real economy. In this way, the vicious circle between banks and sovereigns would be broken. It would also reduce the financial fragmentation recorded in the years of crisis as the result of divergent behaviors in risk premium, lending activities and interest rates between the core and the periphery. In addition, it should strengthen the effectiveness of monetary transmission channels, in particular the credit channels and overflows of liquidity on the money market which, due to the fragmentation of the common financial market, has been significantly disabled in period of crisis. However, contrary to all the positive expectations related to the future functioning of the banking union, major findings of this study indicate that characteristics of the economic system in which the banking union will operate should not be ignored. The euro area is an integration of strong and weak entities with large differences in economic development, wealth, assets of banking systems, growth rates and accountability of fiscal policy. The analysis indicates that low and unbalanced economic growth remains a challenge for the maintenance of financial stability and this problem cannot be resolved just by a single supervision. In many countries bank assets exceed their GDP by several times and large banks are still a matter of concern, because of their systemic importance for individual countries and the euro zone as a whole. The creation of the Single Supervisory Mechanism and the Single Resolution Mechanism is a response to the European crisis, which has particularly affected peripheral countries and caused the associated loop between the banking crisis and the sovereign debt crisis, but has also influenced banks’ balance sheets in the core countries, as the result of crossborder capital flows. The creation of the SSM and the SRM should prevent the similar episodes to happen again and should also provide a new opportunity for strengthening of economic and financial systems of the peripheral countries. On the other hand, there is a potential threat that future focus of the ECB, resolution mechanism and other relevant institutions will be extremely oriented towards large and significant banks (whereby one half of them operate in the core and most important euro area countries), and therefore it remains questionable to what extent will the common resolution funds will be used for rescue of less important institutions. Recent geopolitical developments will be the optimal indicator to show whether the previously established mechanisms are sufficient enough to maintain the adequate financial stability in the euro area market.Keywords: Banking Union, financial integration, single supervisory mechanism (SSM).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16672886 Numerical Study of Modulus of Subgrade Reaction in Eccentrically Loaded Circular Footing Resting
Authors: Seyed Abolhasan Naeini, Mohammad Hossein Zade
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This article is an attempt to present a numerically study of the behaviour of an eccentrically loaded circular footing resting on sand to determine its ultimate bearing capacity. A surface circular footing of diameter 12 cm (D) was used as shallow foundation. For this purpose, three dimensional models consist of foundation, and medium sandy soil was modelled by ABAQUS software. Bearing capacity of footing was evaluated and the effects of the load eccentricity on bearing capacity, its settlement, and modulus of subgrade reaction were studied. Three different values of load eccentricity with equal space from inside the core on the core boundary and outside the core boundary, which were respectively e=0.75, 1.5, and 2.25 cm, were considered. The results show that by increasing the load eccentricity, the ultimate load and the modulus of subgrade reaction decreased.
Keywords: Circular foundation, eccentric loading, sand, modulus of subgrade reaction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16492885 Reliability Indices Evaluation of SEIG Rotor Core Magnetization with Minimum Capacitive Excitation for WECs
Authors: Lokesh Varshney, R. K. Saket
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This paper presents reliability indices evaluation of the rotor core magnetization of the induction motor operated as a self excited induction generator by using probability distribution approach and Monte Carlo simulation. Parallel capacitors with calculated minimum capacitive value across the terminals of the induction motor operated as a SEIG with unregulated shaft speed have been connected during the experimental study. A three phase, 4 poles, 50Hz, 5.5 hp, 12.3A, 230V induction motor coupled with DC Shunt Motor was tested in the electrical machine laboratory with variable reactive loads. Based on this experimental study, it is possible to choose a reliable induction machines operated as a SEIG for unregulated renewable energy application in remote area or where grid is not available. Failure density function, cumulative failure distribution function, survivor function, hazard model, probability of success and probability of failure for reliability evaluation of the three phase induction motor operating as a SEIG have been presented graphically in this paper.
Keywords: Residual magnetism, magnetization curve, induction motor, self excited induction generator, probability distribution, Monte Carlo simulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21272884 Experimental Analysis and Numerical Simulation of Smart Sandwich Beams Behavior in Honeycomb Magnetorheological Elastomer
Authors: A. Khebli, S. Aguib, Y. Kateb, L. Guenfoud, N. Chikh, M. Tourab, T. Djedid, W. Dilmi, A. Hadidi, H. Meglouli
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Composite structures based on magnetorheological elastomers (MREs) are widely used in many industrial sectors, such as automotive, naval, railway, aeronautical, aerospace, and building industries because of their adjustable mechanical properties by an external stimulus. In this work, experimental tests and numerical simulations carried out have shown that the use of these new structures, developed from honeycomb core, and MRE with aluminum skins, make it possible to improve particularly the overall rigidity and to reduce the vibration amplitudes. The results found showed that these hybrid structures have a very good mechanical resistance due mainly to the honeycomb core, and a very good shock absorber due mainly to the core of the MRE. The elaborated composite structure is intended to be used in industrial sectors subject to great efforts and a high amplitude of vibration such as helicopter wings and air turbines.
Keywords: Hybrid sandwich structures, magnetorheological elastomer, honeycomb, 3-point bending, mechanical strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1842883 A Survey on Performance Tools for OpenMP
Authors: Mubarak S. Mohsen, Rosni Abdullah, Yong M. Teo
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Advances in processors architecture, such as multicore, increase the size of complexity of parallel computer systems. With multi-core architecture there are different parallel languages that can be used to run parallel programs. One of these languages is OpenMP which embedded in C/Cµ or FORTRAN. Because of this new architecture and the complexity, it is very important to evaluate the performance of OpenMP constructs, kernels, and application program on multi-core systems. Performance is the activity of collecting the information about the execution characteristics of a program. Performance tools consists of at least three interfacing software layers, including instrumentation, measurement, and analysis. The instrumentation layer defines the measured performance events. The measurement layer determines what performance event is actually captured and how it is measured by the tool. The analysis layer processes the performance data and summarizes it into a form that can be displayed in performance tools. In this paper, a number of OpenMP performance tools are surveyed, explaining how each is used to collect, analyse, and display data collection.Keywords: Parallel performance tools, OpenMP, multi-core.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19232882 Estimation of Groundwater Recovery by Recharge in the Agricultural Area
Authors: Tsutomu Ichikawa
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The Kumamoto area, Kyushu, Japan has 1,041km2 in area and about 1milion in population. This area is a greatest area in Japan which depends on groundwater for all of drinking water. Quantity of this local groundwater use is about 200MCM during the year. It is understood that the main recharging area of groundwater exist in the rice field zone which have high infiltrate height ahead of 100mm/ day of the irrigated water located in the middle area of the Shira-River Basin. However, by decrease of the paddy-rice planting area by urbanization and an acreage reduction policy, the groundwater income and expenditure turned worse. Then Kumamoto city and four companies expended financial support to increase recharging water to underground by ponded water in the field from 2004. In this paper, the author reported the situation of recovery of groundwater by recharge and estimates the efficiency of recharge by statistical method.Keywords: Groundwater recharge, groundwater level, spring water, paddy field.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14222881 Control of Commutation of SR Motor Using Its Magnetic Characteristics and Back-of-Core Saturation Effects
Authors: Dr. N.H. Mvungi
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The control of commutation of switched reluctance (SR) motor has nominally depended on a physical position detector. The physical rotor position sensor limits robustness and increases size and inertia of the SR drive system. The paper describes a method to overcome these limitations by using magnetization characteristics of the motor to indicate rotor and stator teeth overlap status. The method is using active current probing pulses of same magnitude that is used to simulate flux linkage in the winding being probed. A microprocessor is used for processing magnetization data to deduce rotor-stator teeth overlap status and hence rotor position. However, the back-of-core saturation and mutual coupling introduces overlap detection errors, hence that of commutation control. This paper presents the concept of the detection scheme and the effects of backof core saturation.Keywords: Microprocessor control, rotor position, sensorless, switched reluctance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12842880 An Exploration of Sense of Place as Informative for Spatial Planning Guidelines: A Case Study of the Vredefort Dome World Heritage Site, South Africa
Authors: Karen Puren, Ernst Drewes, Vera Roos
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This paper explores the sense of place in the Vredefort Dome World Heritage site, South Africa, as an essential input for the formulation of spatial planning proposals for the area. Intangible aspects such as personal and symbolic meanings of sites are currently not integrated in spatial planning in South Africa. This may have a detrimental effect on local inhabitants who have a long history with the site and built up a strong place identity. Involving local inhabitants at an early stage of the planning process and incorporating their attitudes and opinions in future intervention in the area, may also contribute to the acceptance of the legitimacy of future policy. An interdisciplinary and mixed-method research approach was followed in this study in order to identify possible ways to anchor spatial planning proposals in the identity of the place. In essence, the qualitative study revealed that inhabitants reflect a deep and personal relationship with and within the area, which contributes significantly to their sense of emotional security and selfidentity. Results include a strong conservation-orientated attitude with regard to the natural rural character of the site, especially in the inner core.
Keywords: Place identity, Sense of Place, Spatial Planning, Vredefort Dome World Heritage Site.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25732879 Finite Element Study on Corono-Radicular Restored Premolars
Authors: Sandu L., Topală F., Porojan S.
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Restoration of endodontically treated teeth is a common problem in dentistry, related to the fractures occurring in such teeth and to concentration of forces little information regarding variation of basic preparation guidelines in stress distribution has been available. To date, there is still no agreement in the literature about which material or technique can optimally restore endodontically treated teeth. The aim of the present study was to evaluate the influence of the core height and restoration materials on corono-radicular restored upper first premolar. The first step of the study was to achieve 3D models in order to analyze teeth, dowel and core restorations and overlying full ceramic crowns. The FEM model was obtained by importing the solid model into ANSYS finite element analysis software. An occlusal load of 100 N was conducted, and stresses occurring in the restorations, and teeth structures were calculated. Numerical simulations provide a biomechanical explanation for stress distribution in prosthetic restored teeth. Within the limitations of the present study, it was found that the core height has no important influence on the stress generated in coronoradicular restored premolars. It can be drawn that the cervical regions of the teeth and restorations were subjected to the highest stress concentrations.Keywords: 3D models, finite element analysis, dowel and core restoration, full ceramic crown, premolars, structural simulations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28832878 Effect of Core Stability Ex ercises on Trunk Muscle Balance in Healthy Adult Individuals
Authors: Amira A. A. Abdallah, Amir A. Beltagi
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Background: Core stability training has recently attracted attention for improving muscle balance and optimizing performance in healthy and unhealthy individuals. Purpose: This study investigated the effect of beginner’s core stability exercises on trunk flexors’/extensors’ peak torque ratio and trunk flexors’ and extensors’ peak torques. Methods: Thirty five healthy individuals participated in the study. They were randomly assigned to two groups; experimental “group I, n=20” and control “group II, n=15”. Their mean age, weight and height were 20.7±2.4 vs. 20.3±0.61 years, 66.5±12.1 vs. 68.57±12.2 kg and 166.7±7.8 vs. 164.28 ±7.59 cm. for group I vs. group II. Data were collected using the Biodex Isokinetic system. The participants were tested twice; before and after a 6-week period during which group I performed a core stability training program. Results: The 2x2 Mixed Design ANOVA revealed that there were no significant differences (p>0.025) in the trunk flexors’/extensors’ peak torque ratio between the pre-test and post-test conditions for either group. Moreover, there were no significant differences (p>0.025) in the trunk flexion/extension ratios between both groups at either condition. However, the 2x2 Mixed Design MANOVA revealed significant increases (p<0.025) in the trunk flexors’ and extensors’ peak torques in the post-test condition compared with the pre-test in group I with no significant differences (p>0.025) in group II. Moreover, there was a significant increase (p<0.025) in the trunk flexors’ peak torque only in group I compared with group II in the post-test condition with no significant differences in the other conditions. Interpretation/Conclusion: The improvement in muscle performance indicated by the increase in the trunk flexors’ and extensors’ peak torques in the experimental group recommends including core stability training in the exercise programs that aim to improve muscle performance.
Keywords: Core Stability, Isokinetic, Trunk Muscles.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 36782877 Modal Propagation Properties of Elliptical Core Optical Fibers Considering Stress-Optic Effects
Authors: M. Shah Alam, Sarkar Rahat M. Anwar
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The effect of thermally induced stress on the modal properties of highly elliptical core optical fibers is studied in this work using a finite element method. The stress analysis is carried out and anisotropic refractive index change is calculated using both the conventional plane strain approximation and the generalized plane strain approach. After considering the stress optical effect, the modal analysis of the fiber is performed to obtain the solutions of fundamental and higher order modes. The modal effective index, modal birefringence, group effective index, group birefringence, and dispersion of different modes of the fiber are presented. For propagation properties, it can be seen that the results depend much on the approach of stress analysis.Keywords: Birefringence, dispersion, elliptical core fiber, optical mode analysis, stress-optic effect, stress analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22902876 Comparative Parametric Analysis on the Dynamic Response of Fibre Composite Beams with Debonding
Authors: Indunil Jayatilake, Warna Karunasena
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Fiber Reinforced Polymer (FRP) composites enjoy an array of applications ranging from aerospace, marine and military to automobile, recreational and civil industry due to their outstanding properties. A structural glass fiber reinforced polymer (GFRP) composite sandwich panel made from E-glass fiber skin and a modified phenolic core has been manufactured in Australia for civil engineering applications. One of the major mechanisms of damage in FRP composites is skin-core debonding. The presence of debonding is of great concern not only because it severely affects the strength but also it modifies the dynamic characteristics of the structure, including natural frequency and vibration modes. This paper deals with the investigation of the dynamic characteristics of a GFRP beam with single and multiple debonding by finite element based numerical simulations and analyses using the STRAND7 finite element (FE) software package. Three-dimensional computer models have been developed and numerical simulations were done to assess the dynamic behavior. The FE model developed has been validated with published experimental, analytical and numerical results for fully bonded as well as debonded beams. A comparative analysis is carried out based on a comprehensive parametric investigation. It is observed that the reduction in natural frequency is more affected by single debonding than the equally sized multiple debonding regions located symmetrically to the single debonding position. Thus it is revealed that a large single debonding area leads to more damage in terms of natural frequency reduction than isolated small debonding zones of equivalent area, appearing in the GFRP beam. Furthermore, the extents of natural frequency shifts seem mode-dependent and do not seem to have a monotonous trend of increasing with the mode numbers.
Keywords: Debonding, dynamic response, finite element modelling, FRP beams.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5232875 Steady State Natural Convection in Vertical Heated Rectangular Channel between Two Vertical Parallel MTR-Type Fuel Plates
Authors: Djalal Hamed
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The aim of this paper is to perform an analytic solution of steady state natural convection in a narrow rectangular channel between two vertical parallel MTR-type fuel plates, imposed under a cosine shape heat flux to determine the margin of the nuclear core power at which the natural convection cooling mode can ensure a safe core cooling, where the cladding temperature should not be reach the specific safety limits (90 °C). For this purpose, a simple computer program is developed to determine the principal parameter related to the nuclear core safety such as the temperature distribution in the fuel plate and in the coolant (light water) as a function of the reactor power. Our results are validated throughout a comparison against the results of another published work, which is considered like a reference of this study.Keywords: Buoyancy force, friction force, friction factor, MTR-type fuel, natural convection, vertical heated rectangular channel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7732874 Thermal Characterization of Smart and Large-Scale Building Envelope System in a Subtropical Climate
Authors: Andrey A. Chernousov, Ben Y. B. Chan
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The thermal behavior of a large-scale, phase change material (PCM) enhanced building envelope system was studied in regard to the need for pre-fabricated construction in subtropical regions. The proposed large-scale envelope consists of a reinforced aluminum skin, insulation core, phase change material and reinforced gypsum board. The PCM impact on an energy efficiency of an enveloped room was resolved by validation of the EnergyPlus numerical scheme and optimization of a smart material location in the core. The PCM location was optimized by a minimization method of a cooling energy demand. It has been shown that there is good agreement between the test and simulation results. The optimal location of the PCM layer in Hong Kong summer conditions has been then recomputed for core thicknesses of 40, 60 and 80 mm. A non-dimensional value of the optimal PCM location was obtained to be same for all the studied cases and the considered external and internal conditions.
Keywords: Thermal performance, phase change material, energy efficiency, PCM optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22282873 Inter-Area Oscillation Monitoring in Maghrebian Power Grid Using Phasor Measurement Unit
Authors: M. Tsebia, H. Bentarzi
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In the inter-connected power systems, a phenomenon called inter-area oscillation may be caused by several defects. In this paper, a study of the Maghreb countries inter-area power networks oscillation has been investigated. The inter-area oscillation monitoring can be enhanced by integrating Phasor Measurement Unit (PMU) technology installed in different places. The data provided by PMU and recorded by PDC will be used for the monitoring, analysis, and control purposes. The proposed approach has been validated by simulation using MATLAB/Simulink.
Keywords: Inter-area oscillation, Maghrebian power system, Simulink, PMU.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9782872 Functional Zoning Analysis of Suburban Area of Krasnoyarsk City
Authors: L. Shaporova, Xu Suning, Leng Hong
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Suburban area is an important area to the development of a city and a country. Russias economy is going through major transitions. These transitions are rapidly changing the relationship between cities (urban areas), countryside (rural areas) and the development, growth, and popularity of suburbia. The process of suburbanization takes place in biggest cities of Russia, including Krasnoyarsk City. The modern Krasnoyarsk with a population of about 1mln people occupies the territory of 34115 ha. This article examines the analysis of functions of suburban area and connects these functions with zoning of the suburban territory. The author uses the method of hierarchy to select the best conditions to each function in connection with nature component, transportation and distance from the city. The result of this research is the map of the functional zoning of suburban area of Krasnoyarsk City. The author uses a variety of factors, which have an influence on suburban area, to compare and choose the best conditions. KeywordsSuburban area, zoning of territory, Krasnoyarsk City.
Keywords: Suburban area, zoning of territory, Krasnoyarsk City.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18502871 Investigation of Minor Actinide-Contained Thorium Fuel Impacts on CANDU-Type Reactor Neutronics Using Computational Method
Authors: S. A. H. Feghhi, Z. Gholamzadeh, Z. Alipoor, C. Tenreiro
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Currently, thorium fuel has been especially noticed because of its proliferation resistance than long half-life alpha emitter minor actinides, breeding capability in fast and thermal neutron flux and mono-isotopic naturally abundant. In recent years, efficiency of minor actinide burning up in PWRs has been investigated. Hence, a minor actinide-contained thorium based fuel matrix can confront both proliferation resistance and nuclear waste depletion aims. In the present work, minor actinide depletion rate in a CANDU-type nuclear core modeled using MCNP code has been investigated. The obtained effects of minor actinide load as mixture of thorium fuel matrix on the core neutronics has been studied with comparing presence and non-presence of minor actinide component in the fuel matrix. Depletion rate of minor actinides in the MA-contained fuel has been calculated using different power loads. According to the obtained computational data, minor actinide loading in the modeled core results in more negative reactivity coefficients. The MA-contained fuel achieves less radial peaking factor in the modeled core. The obtained computational results showed 140 kg of 464 kg initial load of minor actinide has been depleted in during a 6-year burn up in 10 MW power.
Keywords: Minor actinide burning, CANDU-type reactor, MCNPX code, Neutronic parameters.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21482870 New DES based on Elliptic Curves
Authors: Ghada Abdelmouez M., Fathy S. Helail, Abdellatif A. Elkouny
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It is known that symmetric encryption algorithms are fast and easy to implement in hardware. Also elliptic curves have proved to be a good choice for building encryption system. Although most of the symmetric systems have been broken, we can create a hybrid system that has the same properties of the symmetric encryption systems and in the same time, it has the strength of elliptic curves in encryption. As DES algorithm is considered the core of all successive symmetric encryption systems, we modified DES using elliptic curves and built a new DES algorithm that is hard to be broken and will be the core for all other symmetric systems.Keywords: DES, Elliptic Curves, hybrid system, symmetricencryption.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17382869 Teaching Science Content Area Literacy to 21st Century Learners
Authors: Melissa C. LaDuke
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The use of new literacies within science classrooms needs to be balanced by teachers to both teach different forms of communication while assessing content area proficiency. Using new literacies such as Twitter and Facebook needs to be incorporated into science content area literacy studies in addition to continuing to use generally-accepted forms of scientific content area presentation which include scientific papers and textbooks. The research question this literature review seeks to answer is “What are some ways in which new forms of literacy are better suited to teach scientific content area literacy to 21st century learners?” The research question is addressed through a literature review that highlights methods currently being used to educate the next wave of learners in the world of science content area literacy. Both temporal discourse analysis (TDA) and critical discourse analysis (CDA) were used to determine the need to use new literacies to teach science content area literacy. Increased use of digital technologies and a change in science content area pedagogy were explored.
Keywords: Science content area literacy, new literacies, critical discourse analysis, temporal discourse analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4692868 Run-Time Customisation of Soft-Core CPUs on Field Programmable Gate Array
Authors: Rehab Abdullah Shendi
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The use of customised soft-core processors in which instructions can be integrated into a system in application hardware is increasing in the Field Programmable Gate Array (FPGA) field. Specifically, the partial run-time reconfiguration of FPGAs in specialised processors for a particular domain can be very beneficial. In this report, the design and implementation for the customisation of a soft-core MIPS processor using an FPGA and partial reconfiguration (PR) of FPGA technology will be addressed to achieve efficient resource use. This can be achieved using a PR design flow that helps the design fit into a smaller device. Moreover, the impact of static power consumption could be reduced due to runtime reconfiguration. This will be done by configurable custom instructions implemented in the hardware as an extension on the MIPS CPU. The aim of this project is to investigate the PR of FPGAs for run-time adaptations of the instruction set of a soft-core CPU, including the integration of custom instructions and the exploration of the potential to use the MultiBoot feature available in Xilinx FPGAs to carry out the PR process. The system will be evaluated and tested on a Nexus 3 development board featuring a Xilinx Spartran-6 FPGA. The system will be able to load reconfigurable custom instructions dynamically into user programs with the help of the trap handler when the custom instruction is called by the MIPS CPU. The results of this experiment demonstrate that custom instructions in hardware can speed up a certain function and many instructions can be saved when compared to a software implementation of the same function. Implementing custom instructions in hardware is perfectly possible and worth exploring.
Keywords: Customisation, FPGA, MIPS, partial reconfiguration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11872867 Low Complexity Multi Mode Interleaver Core for WiMAX with Support for Convolutional Interleaving
Authors: Rizwan Asghar, Dake Liu
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A hardware efficient, multi mode, re-configurable architecture of interleaver/de-interleaver for multiple standards, like DVB, WiMAX and WLAN is presented. The interleavers consume a large part of silicon area when implemented by using conventional methods as they use memories to store permutation patterns. In addition, different types of interleavers in different standards cannot share the hardware due to different construction methodologies. The novelty of the work presented in this paper is threefold: 1) Mapping of vital types of interleavers including convolutional interleaver onto a single architecture with flexibility to change interleaver size; 2) Hardware complexity for channel interleaving in WiMAX is reduced by using 2-D realization of the interleaver functions; and 3) Silicon cost overheads reduced by avoiding the use of small memories. The proposed architecture consumes 0.18mm2 silicon area for 0.12μm process and can operate at a frequency of 140 MHz. The reduced complexity helps in minimizing the memory utilization, and at the same time provides strong support to on-the-fly computation of permutation patterns.Keywords: Hardware interleaver implementation, WiMAX, DVB, block interleaver, convolutional interleaver, hardwaremultiplexing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20362866 Preparation and Characterization of Self Assembled Gold Nanoparticles on Amino Functionalized SiO2 Dielectric Core
Authors: M.E.khosroshahi , M.S.Nourbakhsh
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Wet chemistry methods are used to prepare the SiO2/Au nanoshells. The purpose of this research was to synthesize gold coated SiO2 nanoshells for biomedical applications. Tunable nanoshells were prepared by using different colloidal concentrations. The nanoshells are characterized by FTIR, XRD, UV-Vis spectroscopy and atomic force microscopy (AFM). The FTIR results confirmed the functionalization of the surfaces of silica nanoparticles with NH2 terminal groups. A tunable absorption was observed between 470-600 nm with a maximum range of 530-560 nm. Based on the XRD results three main peaks of Au (111), (200) and (220) were identified. Also AFM results showed that the silica core diameter was about 100 nm and the thickness of gold shell about 10 nm.Keywords: Gold nanoshells, Synthesis, UV-vis spectroscopy, XRD, AFM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32812865 Nonlinear Thermal Hydraulic Model to Analyze Parallel Channel Density Wave Instabilities in Natural Circulation Boiling Water Reactor with Asymmetric Power Distribution
Authors: Sachin Kumar, Vivek Tiwari, Goutam Dutta
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The paper investigates parallel channel instabilities of natural circulation boiling water reactor. A thermal-hydraulic model is developed to simulate two-phase flow behavior in the natural circulation boiling water reactor (NCBWR) with the incorporation of ex-core components and recirculation loop such as steam separator, down-comer, lower-horizontal section and upper-horizontal section and then, numerical analysis is carried out for parallel channel instabilities of the reactor undergoing both in-phase and out-of-phase modes of oscillations. To analyze the relative effect on stability of the reactor due to inclusion of various ex-core components and recirculation loop, marginal stable point is obtained at a particular inlet enthalpy of the reactor core without the inclusion of ex-core components and recirculation loop and then with the inclusion of the same. Numerical simulations are also conducted to determine the relative dominance between two modes of oscillations i.e. in-phase and out-of-phase. Simulations are also carried out when the channels are subjected to asymmetric power distribution keeping the inlet enthalpy same.Keywords: Asymmetric power distribution, Density wave oscillations, In-phase and out-of-phase modes of instabilities, Natural circulation boiling water reactor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22602864 Optimal Assessment of Faulted Area around an Industrial Customer for Critical Sag Magnitudes
Authors: Marios N. Moschakis
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This paper deals with the assessment of faulted area around an industrial customer connected to a particular electric grid that will cause a certain sag magnitude on this customer. The faulted (critical or exposed) area’s length is calculated by adding all line lengths in the neighborhood of the critical node (customer). The applied method is the so-called Method of Critical Distances. By using advanced short-circuit analysis, the Critical Area can be accurately calculated for radial and meshed power networks due to all symmetrical and asymmetrical faults. For the demonstration of the effectiveness of the proposed methodology, a study case is used.
Keywords: Critical area, fault-induced voltage sags, industrial customers, power quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16462863 Hydraulic Studies on Core Components of PFBR
Authors: G. K. Pandey, D. Ramadasu, I. Banerjee, V. Vinod, G. Padmakumar, V. Prakash, K. K. Rajan
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Detailed thermal hydraulic investigations are very essential for safe and reliable functioning of liquid metal cooled fast breeder reactors. These investigations are further more important for components with complex profile, since there is no direct correlation available in literature to evaluate the hydraulic characteristics of such components directly. In those cases available correlations for similar profile or geometries may lead to significant uncertainty in the outcome. Hence experimental approach can be adopted to evaluate these hydraulic characteristics more precisely for better prediction in reactor core components. Prototype Fast Breeder Reactor (PFBR), a sodium cooled pool type reactor is under advanced stage of construction at Kalpakkam, India. Several components of this reactor core require hydraulic investigation before its usage in the reactor. These hydraulic investigations on full scale models, carried out by experimental approaches using water as simulant fluid are discussed in the paper.
Keywords: Fast Breeder Reactor, Cavitation, pressure drop, Reactor components.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29362862 An Improved Design of Area Efficient Two Bit Comparator
Authors: Shashank Gautam, Pramod Sharma
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In present era, development of digital circuits, signal processors and other integrated circuits, magnitude comparators are challenged by large area and more power consumption. Comparator is most basic circuit that performs comparison. This paper presents a technique to design a two bit comparator which consumes less area and power. DSCH and MICROWIND version 3 are used to design the schematic and design the layout of the schematic, observe the performance parameters at different nanometer technologies respectively.
Keywords: Chip design, consumed power, layout area, two bit comparator.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12182861 Information System Security Effectiveness Attributes: A Tanzanian Company Case Study
Authors: Nerey H. Mvungi, Mosses Makoko
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In today-s highly globalised and competitive world access to information plays key role in having an upper hand between business rivals. Hence, proper protection of such crucial resource is core to any modern business. Implementing a successful information security system is basically centered around three pillars; technical solution involving both software and hardware, information security controls to translate the policies and procedure in the system and the people to implement. This paper shows that a lot needs to be done for countries adapting information technology to process, store and distribute information to secure adequately such core resource.Keywords: security, information systems, controls, technology, practices.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2614