Search results for: Adiabatic expansion
129 Phytopathology Prediction in Dry Soil Using Artificial Neural Networks Modeling
Authors: F. Allag, S. Bouharati, M. Belmahdi, R. Zegadi
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The rapid expansion of deserts in recent decades as a result of human actions combined with climatic changes has highlighted the necessity to understand biological processes in arid environments. Whereas physical processes and the biology of flora and fauna have been relatively well studied in marginally used arid areas, knowledge of desert soil micro-organisms remains fragmentary. The objective of this study is to conduct a diversity analysis of bacterial communities in unvegetated arid soils. Several biological phenomena in hot deserts related to microbial populations and the potential use of micro-organisms for restoring hot desert environments. Dry land ecosystems have a highly heterogeneous distribution of resources, with greater nutrient concentrations and microbial densities occurring in vegetated than in bare soils. In this work, we found it useful to use techniques of artificial intelligence in their treatment especially artificial neural networks (ANN). The use of the ANN model, demonstrate his capability for addressing the complex problems of uncertainty data.
Keywords: Desert soil, Climatic changes, Bacteria, Vegetation, Artificial neural networks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1890128 Variable Rate Superorthogonal Turbo Code with the OVSF Code Tree
Authors: Insah Bhurtah, P. Clarel Catherine, K. M. Sunjiv Soyjaudah
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When using modern Code Division Multiple Access (CDMA) in mobile communications, the user must be able to vary the transmission rate of users to allocate bandwidth efficiently. In this work, Orthogonal Variable Spreading Factor (OVSF) codes are used with the same principles applied in a low-rate superorthogonal turbo code due to their variable-length properties. The introduced system is the Variable Rate Superorthogonal Turbo Code (VRSTC) where puncturing is not performed on the encoder’s final output but rather before selecting the output to achieve higher rates. Due to bandwidth expansion, the codes outperform an ordinary turbo code in the AWGN channel. Simulations results show decreased performance compared to those obtained with the employment of Walsh-Hadamard codes. However, with OVSF codes, the VRSTC system keeps the orthogonality of codewords whilst producing variable rate codes contrary to Walsh-Hadamard codes where puncturing is usually performed on the final output.
Keywords: CDMA, MAP Decoding, OVSF, Superorthogonal Turbo Code.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2176127 Applications of Carbon Fibers Produced from Polyacrylonitrile Fibers
Authors: R. Eslami Farsani, R. Fazaeli
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Carbon fibers have specific characteristics in comparison with industrial and structural materials used in different applications. Special properties of carbon fibers make them attractive for reinforcing and fabrication of composites. These fibers have been utilized for composites of metals, ceramics and plastics. However, it-s mainly used in different forms to reinforce lightweight polymer materials such as epoxy resin, polyesters or polyamides. The composites of carbon fiber are stronger than steel, stiffer than titanium, and lighter than aluminum and nowadays they are used in a variety of applications. This study explains applications of carbon fibers in different fields such as space, aviation, transportation, medical, construction, energy, sporting goods, electronics, and the other commercial/industrial applications. The last findings of composites with polymer, metal and ceramic matrices containing carbon fibers and their applications in the world investigated. Researches show that carbon fibers-reinforced composites due to unique properties (including high specific strength and specific modulus, low thermal expansion coefficient, high fatigue strength, and high thermal stability) can be replaced with common industrial and structural materials.Keywords: Polyacrylonitrile Fibers, Carbon Fibers, Application
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4847126 The Public Law Studies: Relationship between Accountability, Environmental Education and Smart Cities
Authors: Aline Alves Bandeira, Luís Pedro Lima, Maria Cecília de Paula Silva, Paulo Henrique de Viveiros Tavares
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Nowadays, the study of public policies regarding management efficiency is essential. Public policies are about what governments do or do not do, being an area that has grown worldwide, contributing through the knowledge of technologies and methodologies that monitor and evaluate the performance of public administrators. The information published on official government websites needs to provide for transparency and responsiveness of managers. Thus, transparency is a primordial factor for the execution of accountability, providing, in this way, services to the citizen with the expansion of transparent, efficient, democratic information and that value administrative eco-efficiency. The ecologically balanced management of a Smart City must optimize environmental education, building a fairer society, which brings about equality in the use of quality environmental resources. Smart Cities add value in the construction of public management, enabling interaction between people, enhancing environmental education and the practical applicability of administrative eco-efficiency, fostering economic development and improving the quality of life.
Keywords: Accountability, environmental education, new public administration, smart cities.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 620125 Mapping Soil Fertility at Different Scales to Support Sustainable Brazilian Agriculture
Authors: Rachel Bardy Prado, Vinícius de Melo Benites, José Carlos Polidoro, Carlos Eduardo Gonçalves, Alexey Naumov
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Most agricultural crops cultivated in Brazil are highly nutrient demanding. Brazilian soils are generally acidic with low base saturation and available nutrients. Demand for fertilizer application has increased because the national agricultural sector expansion. To improve productivity without environmental impact, there is the need for the utilization of novel procedures and techniques to optimize fertilizer application. This includes the digital soil mapping and GIS application applied to mapping in different scales. This paper is based on research, realized during 2005 to 2010 by Brazilian Corporation for Agricultural Research (EMBRAPA) and its partners. The purpose was to map soil fertility in national and regional scales. A soil profile data set in national scale (1:5,000,000) was constructed from the soil archives of Embrapa Soils, Rio de Janeiro and in the regional scale (1:250,000) from COMIGO Cooperative soil data set, Rio Verde, Brazil. The mapping was doing using ArcGIS 9.1 tools from ESRI.Keywords: agricultural sustainability, fertilizer optimization, GIS, soil attributes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2618124 Single Phase Fluid Flow in Series of Microchannel Connected via Converging-Diverging Section with or without Throat
Authors: Abhishek Kumar Chandra, Kaushal Kishor, Wasim Khan, Dhananjay Singh, M. S. Alam
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Single phase fluid flow through series of uniform microchannels connected via transition section (converging-diverging section with or without throat) was analytically and numerically studied to characterize the flow within the channel and in the transition sections. Three sets of microchannels of diameters 100, 184, and 249 μm were considered for investigation. Each set contains 10 numbers of microchannels of length 20 mm, connected to each other in series via transition sections. Transition section consists of either converging-diverging section with throat or without throat. The effect of non-uniformity in microchannels on pressure drop was determined by passing water/air through the set of channels for Reynolds number 50 to 1000. Compressibility and rarefaction effects in transition sections were also tested analytically and numerically for air flow. The analytical and numerical results show that these configurations can be used in enhancement of transport processes. However, converging-diverging section without throat shows superior performance over with throat configuration.Keywords: Contraction-expansion flow, integrated microchannel, microchannel network, single phase flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 909123 Low-Latency and Low-Overhead Path Planning for In-band Network-Wide Telemetry
Authors: Penghui Zhang, Hua Zhang, Jun-Bo Wang, Cheng Zeng, Zijian Cao
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With the development of software-defined networks and programmable data planes, in-band network telemetry (INT) has become an emerging technology in communications because it can get accurate and real-time network information. However, due to the expansion of the network scale, existing telemetry systems, to the best of the authors’ knowledge, have difficulty in meeting the common requirements of low overhead, low latency and full coverage for traffic measurement. This paper proposes a network-wide telemetry system with a low-latency low-overhead path planning (INT-LLPP). This paper builds a mathematical model to analyze the telemetry overhead and latency of INT systems. Then, we adopt a greedy-based path planning algorithm to reduce the overhead and latency of the network telemetry with the full network coverage. The simulation results show that network-wide telemetry is achieved and the telemetry overhead can be reduced significantly compared with existing INT systems. INT-LLPP can control the system latency to get real-time network information.
Keywords: Network telemetry, network monitoring, path planning, low latency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 255122 Utilization of Mustard Leaves (Brassica juncea) Powder for the Development of Cereal Based Extruded Snacks
Authors: Maya S. Rathod, Bahadur Singh Hathan
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Mustard leaves are rich in folates, vitamin A, K and B-complex. Mustard greens are low in calories and fats and rich in dietary fiber. They are rich in potassium, manganese, iron, copper, calcium, magnesium and low in sodium. It is very rich in antioxidants and Phytonutrients. For the optimization of process variables (moisture content and mustard leave powder), the experiments were conducted according to central composite Face Centered Composite design of RSM. The mustard leaves powder was replaced with composite flour (a combination of rice, chickpea and corn in the ratio of 70:15:15). The extrudate was extruded in a twin screw extruder at a barrel temperature of 120°C. The independent variables were mustard leaves powder (2-10 %) and moisture content (12-20 %). Responses analyzed were bulk density, water solubility index, water absorption index, lateral expansion, antioxidant activity, total phenolic content, and overall acceptability. The optimum conditions obtained were 7.19 g mustard leaves powder in 100g premix having 16.8% moisture content (w.b).Keywords: Extrusion, mustard leaves powder, optimization, response surface methodology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2173121 Study about the Development of Small Towns in the Metropolitan Fringe in Developed Area of China–A Case Study of Sandun Town in Hangzhou
Authors: Haifeng Jiao, Chuankun Rao
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Due to the Rapid Urbanization in China, the influence of metropolises to surrounding areas grows by a tremendous speed in developed region. One of the most obvious influences is the expansion of the urban built-up areas which covers the land belongs to small towns. Around metropolitan fringe, the boundary between city and village becomes more and more obscure. So being the most sensitive area, the small towns on the fringe of metropolises have the special meaning on the research into the small towns- development. This paper chooses Sandun Town in Hangzhou of Zhejiang Province as an example, emphatically focus on aspects such as the central area proliferation, the industrial shift, the position effect, the subway effect and the commercial development, reviews a few problems of small towns in the future and the important problems in their planning by the analysis of the characteristics of the present conditions and the developing motive mechanism, so that guides small towns to develop properly by liking with these small towns and center metropolises.
Keywords: Metropolitan fringe, Small towns, Sandun Town, Motive mechanism.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1620120 Synthesizing CuFe2O4 Spinel Powders by a Combustion-Like Process for Solid Oxide Fuel Cell Interconnect Coatings
Authors: S. N. Hosseini, M. H. Enayati, F. Karimzadeh, N. M. Sammes
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The synthesis of CuFe2O4 spinel powders by an optimized combustion-like process followed by calcination is described herein. The samples were characterized using X-ray diffraction (XRD), differential thermal analysis (TG/DTA), scanning electron microscopy (SEM), dilatometry and 4-probe DC methods. Different glycine to nitrate (G/N) ratios of 1 (fuel-deficient), 1.48 (stoichiometric) and 2 (fuel-rich) were employed. Calcining the asprepared powders at 800 and 1000°C for 5 hours showed that the G/N ratio of 2 results in the formation of the desired copper spinel single phase at both calcination temperatures. For G/N=1, formation of CuFe2O4 takes place in three steps. First, iron and copper nitrates decompose to iron oxide and pure copper. Then, copper transforms to copper oxide and finally, copper and iron oxides react with each other to form a copper ferrite spinel phase. The electrical conductivity and the coefficient of thermal expansion of the sintered pelletized samples were 2 S.cm-1 (800°C) and 11×10-6 °C-1 (25-800°C), respectively.Keywords: SOFC interconnect coatings, Copper ferrite, Spinels, Electrical conductivity, Glycine–nitrate process.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2484119 “Context” Thinking of Contemporary Urban History Space under the Basis of Enlightenment of Chinese Traditional Cultural Philology - Taking West Expansion Plan of Tianyi Pavilion as an Example
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Facing the understanding problem of update and preservation of urban history space under background of rapid Chinese urbanization, so at first there is a need to dig the philosophic principles of “antithesis” and “unification” which are contained in the traditional Chinese literature known as “antithesis” and do the job of planning translation by personal understanding in order to form understanding and value systems of dialectical urban history space under the foundation of “antithesis”. Then we could put forward a “context” concept for urban history space under the foregoing basis. After that, we will take the update and preservation of Ningbo Tianyi Pavilion’s historical district as an example to discuss problems related to understanding of urban history area under the basis of Chinese tradition culture, improvement of value system, construction of urban trait space and Chinese “localization” of planning theory.
Keywords: Antithesis, traditional values, City renewal and conservation, the “context” of city history space.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1799118 High Temperature Oxidation of Cr-Steel Interconnects in Solid Oxide Fuel Cells
Authors: Saeed Ghali, Azza Ahmed, Taha Mattar
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Solid Oxide Fuel Cell (SOFC) is a promising solution for the energy resources leakage. Ferritic stainless steel becomes a suitable candidate for the SOFCs interconnects due to the recent advancements. Different steel alloys were designed to satisfy the needed characteristics in SOFCs interconnect as conductivity, thermal expansion and corrosion resistance. Refractory elements were used as alloying elements to satisfy the needed properties. The oxidation behaviour of the developed alloys was studied where the samples were heated for long time period at the maximum operating temperature to simulate the real working conditions. The formed scale and oxidized surface were investigated by SEM. Microstructure examination was carried out for some selected steel grades. The effect of alloying elements on the behaviour of the proposed interconnects material and the performance during the working conditions of the cells are explored and discussed. Refractory metals alloying of chromium steel seems to satisfy the needed characteristics in metallic interconnects.
Keywords: SOFCs, Cr-steel, interconnects, oxidation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1225117 Synthesis, Structure and Properties of NZP/NASICON Structured Materials
Authors: E. A. Asabina, V. I. Pet'kov, P. A. Mayorov, A. V. Markin, N. N. Smirnova, A. M. Kovalskii, A. A. Usenko
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The purpose of this work was to synthesize and investigate phase formation, structure and thermophysical properties of the phosphates M0.5+xM'xZr2–x(PO4)3 (M – Cd, Sr, Pb; M' – Mg, Co, Mn). The compounds were synthesized by sol-gel method. The results showed formation of limited solid solutions of NZP/NASICON type. The crystal structures of triple phosphates of the compositions MMg0.5Zr1.5(PO4)3 were refined by the Rietveld method using XRD data. Heat capacity (8–660 K) of the phosphates Pb0.5+xMgxZr2-x(PO4)3 (x = 0, 0.5) was measured, and reversible polymorphic transitions were found at temperatures, close to the room temperature. The results of Rietveld structure refinement showed the polymorphism caused by disordering of lead cations in the cavities of NZP/NASICON structure. Thermal expansion (298−1073 K) of the phosphates MMg0.5Zr1.5(PO4)3 was studied by XRD method, and the compounds were found to belong to middle and low-expanding materials. Thermal diffusivity (298–573 K) of the ceramic samples of phosphates slightly decreased with temperature increasing. As was demonstrated, the studied phosphates are characterized by the better thermophysical characteristics than widespread fire-resistant materials, such as zirconia and etc.
Keywords: NASICON, NZP, phosphate, structure, synthesis, thermophysical properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 841116 Compressible Lattice Boltzmann Method for Turbulent Jet Flow Simulations
Authors: K. Noah, F.-S. Lien
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In Computational Fluid Dynamics (CFD), there are a variety of numerical methods, of which some depend on macroscopic model representatives. These models can be solved by finite-volume, finite-element or finite-difference methods on a microscopic description. However, the lattice Boltzmann method (LBM) is considered to be a mesoscopic particle method, with its scale lying between the macroscopic and microscopic scales. The LBM works well for solving incompressible flow problems, but certain limitations arise from solving compressible flows, particularly at high Mach numbers. An improved lattice Boltzmann model for compressible flow problems is presented in this research study. A higher-order Taylor series expansion of the Maxwell equilibrium distribution function is used to overcome limitations in LBM when solving high-Mach-number flows. Large eddy simulation (LES) is implemented in LBM to simulate turbulent jet flows. The results have been validated with available experimental data for turbulent compressible free jet flow at subsonic speeds.
Keywords: Compressible lattice Boltzmann metho-, large eddy simulation, turbulent jet flows.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 955115 Shadow Imaging Study of Z-Pinch Dynamic Hohlraum
Authors: Chen Faxin, Feng Jinghua, Yang Jianlun, Li Linbo, Zhou Lin
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In order to obtaining the dynamic evolution image of Tungsten array for foam padding, and to research the form of interaction between Tungsten plasma and foam column, a shadow imaging system of four-frame ultraviolet probe laser (266nm)has been designed on 1MA pulse power device. The time resolution of the system is 2.5ns, and static space resolution is superior to 70μm. The radial shadowgraphy image reveals the whole process from the melting and expansion of solid wire to the interaction of the precursor plasma and the foam, from the pinch to rebound inflation. The image shows the continuous interaction of Tungsten plasma and foam in a form of “Raining" within a time of about 50ns, the plasma shell structure has not been found in the whole period of pinch. The quantitative analysis indicates the minimum pinching speed of the foam column is 1.0×106cm/s, and maximum pinching speed is 6.0×106cm/s, and the axial stagnation diameter is approx 1mm.
Keywords: Dynamic hohlraum, Shadowgraphy image, Foam evolution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1920114 Matching Farmer Competence and Farm Resources with the Transformation of Agri-Food Marketing Systems
Authors: Bhawat Chiamjinnawat
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The agri-food market transformation has implied market growth for the fruit industry in Thailand. This article focuses on analysis of farmer competence and farm resources which affect market strategies used by fruit farmers in Chanthaburi province of Thailand. The survey data were collected through the use of face-to-face interviews with structured questionnaires. This study identified 14 drivers related to farmer competence and farm resources of which some had significant effect on the decision to use either high-value markets or traditional markets. The results suggest that farmers who used high-value markets were better educated and they had longer experience and larger sized business. Identifying the important factors that match with the market transformation provides policy with opportunities to support the fruit farmers to increase their market power. Policies that promote business expansion of agricultural cooperatives and knowledge sharing among farmers are recommended to reduce limitations due to limited knowledge, low experience, and small business sizes.
Keywords: Farmer competence, farm resources, fruit industry, high-value markets, Thailand.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1256113 The State Support to the Tourism Policy Formation Mechanism in Black Sea Basin Countries (Azerbaijan, Turkey, Russia, Georgia) and Its Impact on Sustainable Tourism Development
Authors: A. Bahar Ganiyeva, M. Sabuhi Tanriverdiyev
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The article analyzes state support and policy mechanisms aimed at driving tourism as one of the vibrant and rapidly developing economies. State programs and long-range strategic roadmaps and previous programs execution, results and their impact on the particular countries economy have been raised during the research. This theme provides a useful framework for discussions with a wider range of stakeholders as the implications arising are of importance both for academics and practitioners engaged in hospitality and tourism development and research. The impact that tourism has on sustainable regional development in emerging markets is highly substantial. For Azerbaijan, Turkey, Georgia, and Russia, with their rich natural resources and cultural heritage, tourism can be an important basis for economic expansion, and a way to form an acceptable image of the countries as safe, open, hospitable, and complex.
Keywords: Sustainable tourism, hospitality, destination, strategic roadmap, tourism, economy, growth, state support, mechanism, policy formation, state program.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 862112 Analyzing the Market Growth in API Economy Using Time-Evolving Model
Authors: Hiroki Yoshikai, Shin’ichi Arakawa, Tetsuya Takine, Masayuki Murata
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API (Application Programming Interface) economy is expected to create new value by converting corporate services such as information processing and data provision into APIs and using these APIs to connect services. Understanding dynamics of a market of API economy under strategies of participants is crucial to fully maximize the values of API economy. To capture the behavior of a market in which the number of participants changes over time, we present a time-evolving market model for a platform in which API providers who provide APIs to service providers participate in addition to service providers and consumers. Then, we use the market model to clarify the role API providers play in expanding market participants and forming ecosystems. The results show that the platform with API providers increased the number of market participants by 67% and decreased the cost to develop services by 25% compared to the platform without API providers. Furthermore, during the expansion phase of the market, it is found that the profits of participants are mostly the same when 70% of the revenue from consumers is distributed to service providers and API providers. It is also found that, when the market is mature, the profits of the service provider and API provider will decrease significantly due to their competitions and the profit of the platform increases.
Keywords: API Economy, ecosystem, platform, API providers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 243111 Daily Site Risks Associated with Construction Projects and On-spot Corrective Measurements: Case Study of Revamping Projects in Kuwait Oil Company Fields Area
Authors: Yousef S. Al-Othman
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The growth and expansion of the industrial facilities comes proportional to the market increasing demand of products and services. Furthermore, raw material producers such as oil companies usually undergo massive revamping projects to maintain a synchronized supply. These revamping projects are usually delivered through challenging construction projects held and associated with daily site risks related to the construction process. Henceforth, a case study related to these risks and corresponding on-spot corrective measurements has been made on a certain number of construction project contractors at Kuwait Oil Company (KOC) to derive the benefits and overall effectiveness of the on-spot corrective measurements during the construction phase of a project, and how would the same help in avoiding major incidents, ensuring a smooth, cost effective and on time delivery of the project. Findings of this case study shall have an added value to the overall risk management process by minimizing the daily site risks that may affect the project lead time, resulting in an undisturbed on-site construction process.
Keywords: Oil and gas, risk management, construction projects, project lead time.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 892110 Stress Analysis of Adhesively Bonded Double- Lap Joints Subjected to Combined Loading
Authors: Solyman Sharifi, Naghdali Choupani
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Adhesively bonded joints are preferred over the conventional methods of joining such as riveting, welding, bolting and soldering. Some of the main advantages of adhesive joints compared to conventional joints are the ability to join dissimilar materials and damage-sensitive materials, better stress distribution, weight reduction, fabrication of complicated shapes, excellent thermal and insulation properties, vibration response and enhanced damping control, smoother aerodynamic surfaces and an improvement in corrosion and fatigue resistance. This paper presents the behavior of adhesively bonded joints subjected to combined thermal loadings, using the numerical methods. The joint configuration considers aluminum as central adherend with six different outer adherends including aluminum, steel, titanium, boronepoxy, unidirectional graphite-epoxy and cross-ply graphite-epoxy and epoxy-based adhesives. Free expansion of the joint in x direction was permitted and stresses in adhesive layer and interfaces calculated for different adherends.Keywords: Thermal stress, patch repair, Adhesive joint, Finiteelement analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2877109 Heat Transfer to Laminar Flow over a Double Backward-Facing Step
Authors: Hussein Togun, Tuqa Abdulrazzaq, S. N. Kazi, A. Badarudin, M. K. A. Ariffin
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Heat transfer and laminar air flow over a double backward-facing step numerically studied in this paper. The simulations was performed by using ANSYS ICEM for meshing process and using ANSYS fluent 14 (CFD) for solving. The k-ɛ standard model adopted with Reynolds number varied between 98.5 to 512 and three step height at constant heat flux (q=2000 W/m2). The top of wall and bottom of upstream are insulated with bottom of downstream is heated. The results show increase in Nusselt number with increases of Reynolds number for all cases and the maximum of Nusselt number happens at the first step in compared to the second step. Due to increase of cross section area of downstream to generate sudden expansion then Nusselt number decrease but the profile of Nusselt number keep same trend for all cases where increase after the first and second steps. Recirculation region after the first and second steps are denoted by contour of streamline velocity. The higher augmentation of heat transfer rate observed for case 1 at Reynolds number of 512 and heat flux q=2000 W/m2.
Keywords: Laminar flow, Double backward, Separation flow, Recirculation flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3508108 Simplified Models to Determine Nodal Voltagesin Problems of Optimal Allocation of Capacitor Banks in Power Distribution Networks
Authors: A. Pereira, S. Haffner, L. V. Gasperin
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This paper presents two simplified models to determine nodal voltages in power distribution networks. These models allow estimating the impact of the installation of reactive power compensations equipments like fixed or switched capacitor banks. The procedure used to develop the models is similar to the procedure used to develop linear power flow models of transmission lines, which have been widely used in optimization problems of operation planning and system expansion. The steady state non-linear load flow equations are approximated by linear equations relating the voltage amplitude and currents. The approximations of the linear equations are based on the high relationship between line resistance and line reactance (ratio R/X), which is valid for power distribution networks. The performance and accuracy of the models are evaluated through comparisons with the exact results obtained from the solution of the load flow using two test networks: a hypothetical network with 23 nodes and a real network with 217 nodes.Keywords: Distribution network models, distribution systems, optimization, power system planning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1562107 Farming Production in Brazil: Innovation and Land-Sparing Effect
Authors: Isabela Romanha de Alcantara, José Eustáquio Ribeiro Vieira Filho, José Garcia Gasques
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Innovation and technology can be determinant factors to ensure agricultural and sustainable growth, as well as productivity gains. Technical change has contributed considerably to supply agricultural expansion in Brazil. This agricultural growth could be achieved by incorporating more land or capital. If capital is the main source of agricultural growth, it is possible to increase production per unit of land. The objective of this paper is to estimate: 1) total factor productivity (TFP), which is measured in terms of the rate of output per unit of input; and 2) the land-saving effect (LSE) that is the amount of land required in the case that yield rate is constant over time. According to this study, from 1990 to 2019, it appears that 87% of Brazilian agriculture product growth comes from the gains of productivity; the remaining 13% comes from input growth. In the same period, the total LSE was roughly 400 Mha, which corresponds to 47% of the national territory. These effects reflect the greater efficiency of using productive factors, whose technical change has allowed an increase in the agricultural production based on productivity gains.
Keywords: agriculture, land-saving effect, livestock, productivity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 793106 Current Situation of Maritime Transport and Logistics in Myanmar
Authors: S. N. S. Thein, H. L. Yang, Z. B. Liu
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There are many modes of transport. Among them, maritime transport is a major transportation mode of international trade. In the Republic of the Union of Myanmar (Burma), water transportation served as one of the most important modes of transport for country's exports and imports. Getting the accurate information and data-gathering activity are the most important aspects for any study field. Therefore, in this research, a historical review of the development of ports in Myanmar and how they have changed had been carried out. All the relevant literature and documents have also been reviewed, studied, and organized. The sources of collected data are from reports, journals, internet, as well as from the publications of authorized organizations and international associations. To get better understanding about real situation of maritime transport and logistics in Myanmar; current condition of existing ports, expansion and on-going projects, and future port development plans are described successively. Hence, the main purpose of this study is to build up a comprehensive picture of maritime transport and logistics, in addition to border trade within ASEAN and Myanmar. It will help for academic researchers, decision makers, and stakeholders for national planning as well as for the local and foreign investors to recognize current situation of maritime transport and logistics in Myanmar.
Keywords: ASEAN, border trade, logistics, maritime transport, ports of Myanmar.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1350105 Treatment of Inorganic Filler Surface by Silane-Coupling Agent: Investigation of Treatment Condition and Analysis of Bonding State of Reacted Agent
Authors: Hiroshi Hirano, Joji Kadota, Toshiyuki Yamashita, Yasuyuki Agari
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It is well known that enhancing interfacial adhesion between inorganic filler and matrix resin in a composite lead to favorable properties such as excellent mechanical properties, high thermal resistance, prominent electric insulation, low expansion coefficient, and so on. But it should be avoided that much excess of coupling agent is reacted due to a negative impact of their final composite-s properties. There is no report to achieve classification of the bonding state excepting investigation of coating layer thickness. Therefore, the analysis of the bonding state of the coupling agent reacted with the filler surface such as BN particles with less functional group and silica particles having much functional group was performed by thermal gravimetric analysis and pyrolysis GC/MS. The reacted number of functional groups on the silane-coupling agent was classified as a result of the analysis. Thus, we succeeded in classifying the reacted number of the functional groups as a result of this study.Keywords: Inorganic filler, boron nitride, surface treatment, coupling agent, analysis of bonding state
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5043104 On the Transition of Europe’s Power Sector: Economic Consequences of National Targets
Authors: Geoffrey J. Blanford, Christoph Weissbart
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The prospects for the European power sector indicate that it has to almost fully decarbonize in order to reach the economy-wide target of CO2-emission reduction. We apply the EU-REGEN model to explain the penetration of RES from an economic perspective, their spatial distribution, and the complementary role of conventional generation technologies. Furthermore, we identify economic consequences of national energy and climate targets. Our study shows that onshore wind power will be the most crucial generation technology for the future European power sector. Its geographic distribution is driven by resource quality. Gas power will be the major conventional generation technology for backing-up wind power. Moreover, a complete phase out of coal power proves to be not economically optimal. The paper demonstrates that existing national targets have a negative impact, especially on the German region with higher prices and lower revenues. The remaining regions profit are hardly affected. We encourage an EU-wide coordination on the expansion of wind power with harmonized policies. Yet, this requires profitable market structures for both, RES and conventional generation technologies.
Keywords: European decarbonization pathway, power market investment, public policies, technology choice.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 924103 On the Exact Solution of Non-Uniform Torsion for Beams with Axial Symmetric Cross-Section
Authors: A.Campanile, M. Mandarino, V. Piscopo, A. Pranzitelli
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In the traditional theory of non-uniform torsion the axial displacement field is expressed as the product of the unit twist angle and the warping function. The first one, variable along the beam axis, is obtained by a global congruence condition; the second one, instead, defined over the cross-section, is determined by solving a Neumann problem associated to the Laplace equation, as well as for the uniform torsion problem. So, as in the classical theory the warping function doesn-t punctually satisfy the first indefinite equilibrium equation, the principal aim of this work is to develop a new theory for non-uniform torsion of beams with axial symmetric cross-section, fully restrained on both ends and loaded by a constant torque, that permits to punctually satisfy the previous equation, by means of a trigonometric expansion of the axial displacement and unit twist angle functions. Furthermore, as the classical theory is generally applied with good results to the global and local analysis of ship structures, two beams having the first one an open profile, the second one a closed section, have been analyzed, in order to compare the two theories.Keywords: Non-uniform torsion, Axial symmetric cross-section, Fourier series, Helmholtz equation, FE method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2363102 Using New Technologies for Public Parking in Isfahan City
Authors: M. Ahmadi Baseri, R. Mokhtari Malekabadi, A. Gandomkar
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Cities expansion, urban travels increase, the technology development, the automobile price cheapen, and the families' income ascending cause the considerable increase in automobile numbers of the city. This fact has led to the traffic creation and the automobile parking site shortage in the city. Also in Esfahan metropolis, the parking lots shortage has been the great problem of this town; in addition, in designing and constructing of the parking sites the traditional methods are utilized which do not have a reasonable and optimized usage of the valuable urban lands. In this article, by introducing the prefabricate mechanized parking system which is inexpensive, simple and quick, and occupies very small space, therefore provides the high content of parking site for the cities, we can eliminate the parking space shortage difficulty of the cities. The achieved results of this research represent that an optimized utilization of the existent urban spaces for parking site construction has not been accomplished. By employing the new parking site technologies such as mechanization categorized parking sites and the capacity prefabricate mechanized of each parking space have become 8 multiples; in this case, the valuable urban lands can be used in an optimized way.Keywords: Public parking sites, New parking sites technologies, Prefabricate mechanized parking site, Isfahan City.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1811101 Technological Deep Assessment of Automotive Parts Manufacturers Case of Iranian Manufacturers
Authors: Manouchehre Ansari, Mahmoud Dehghan Nayeri, Reza Yousefi Zenouz
Abstract:
In order to develop any strategy, it is essential to first identify opportunities, threats, weak and strong points. Assessment of technology level provides the possibility of concentrating on weak and strong points. The results of technology assessment have a direct effect on decision making process in the field of technology transfer or expansion of internal research capabilities so it has a critical role in technology management. This paper presents a conceptual model to analyze the technology capability of a company as a whole and in four main aspects of technology. This model was tested on 10 automotive parts manufacturers in IRAN. Using this model, capability level of manufacturers was investigated in four fields of managing aspects, hard aspects, human aspects, and information and knowledge aspects. Results show that these firms concentrate on hard aspect of technology while others aspects are poor and need to be supported more. So this industry should develop other aspects of technology as well as hard aspect to have effective and efficient use of its technology. These paper findings are useful for the technology planning and management in automotive part manufactures in IRAN and other Industries which are technology followers and transport their needed technologies.Keywords: Technology, Technological evaluation, TechnologyMaturity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1737100 Assessment of the Benefits of Renewable Energy to the Azerbaijan Ecosystem
Authors: N. S. Imamverdiyev
Abstract:
The transition to renewable energy sources has become a critical component of global efforts to mitigate climate change and promote sustainable development. However, the deployment of renewable energy technologies can also have significant impacts on ecosystems and the services they provide, such as carbon sequestration, soil fertility, water quality, and biodiversity. These technologies also highlight the potential co-benefits of renewable energy deployment for ecosystem services, such as reducing greenhouse gas emissions and improving air and water quality. Renewable energy sources, such as wind, solar, hydro, and biomass, are increasingly being used to meet the world's energy needs due to their environmentally friendly nature and the desire to reduce greenhouse gas emissions. However, the expansion of renewable energy infrastructure can also impact ecosystem services, which are the benefits that humans derive from nature, such as clean water, air, and food. This geographic assessment aims to evaluate the relationship between renewable energy infrastructure and ecosystem services. Potential solutions such as the use of ecological benefit measures, biodiversity-friendly design of renewable energy infrastructure, and stakeholder participation in decision-making processes are being investigated to determine the positive effects of renewable energy infrastructure on ecosystem services.
Keywords: Renewable energy, solar energy, climate change, energy production.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 193