Search results for: concrete gravity dam
802 Argumentative and Enunciative Analysis of Spanish Political Discourse
Authors: Cristina Diez
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One of the most important challenges of discourse analysis is to find the linguistic mechanisms of subjectivity. The present article aims to raise the need for an argumentative and enunciative analysis to reach the subjective tissue of language. The intention is to prove that the instructions inscribed in the own language are those that indicate how a statement is to be interpreted and that the argumentative value is implied at the semantic level. For that, the theory of argumentation from Ducrot and Anscombre will be implemented. First, a reflection on the study about subjectivity and enunciation in language will be exposed, followed by concrete proposals on the linguistic mechanisms that speakers use either consciously or unconsciously, to finally focus on those argumentative tools that political discourse uses in order to influence the audience.Keywords: argumentation, enunciation, discourse analysis, subjectivity
Procedia PDF Downloads 201801 Characterization of Biodiesel Produced from Cow-Tallow
Authors: Nwadike Emmanuel Chinagoron, Achebe Chukwunonso, Ezeliora Chukwuemeka Daniel, Azaka Onyemazuwa Andrew
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In this research work, the process of biodiesel production in a pilot plant was studied using cow tallow as raw material, methanol as the solvent and potassium hydroxide as catalysts. The biodiesel quality was determined by characterization. The tallow used in the production had a molecular weight of 860g. Its oil had a density value of 0.8g/ml, iodine value of 63.45, viscosity at 300C was 9.83pas, acid value was 1.96, free fatty acid (FFA) of 0.98%, saponification value of 82.75mleq/kg, specific gravity of 0.898, flash point of 1100C, cloud point of 950C and Calorific value also called Higher Heating Value (HHV) of 38.365MJ/Kg. The produced biodiesel had a density of 0.82g/ml, iodine value of 126.9, viscosity of 4.32pas at 300C, acid value of 0.561, FFA of 0.2805%, saponification value of 137.45 mleq/kg.Flash point, cloud point and centane number of the biodiesel produced are 1390C, 980C and 57.5 respectively, with fat content, protein content, ash content, moisture content, fiber content and carbohydrate content values of 10%, 2.8%, 5%, 5%, 20%, and 37.2% respectively. The biodiesel higher heating values (calorific values) when estimated from viscosity, density and flash points were 41.4MJ/Kg, 63.8MJ/Kg, and 34.6MJ/Kg respectively. The biodiesel was blended with conventional diesel. The blend B-10 had values of 1320C and 960C for flash and cloud points, with Calorific value (or HHV) of 34.6 MJ/Kg (when estimated from its Flash point) and fat content, protein content, ash content, moisture content, fiber content and carbohydrate content values of 5%, 2.1%,10%, 5%, 15%, and 62.9% respectively.Keywords: biodiesel, characterization, cow-tallow, cetane rating
Procedia PDF Downloads 537800 Calculating Quantity of Steel Bar Placed in Mesh Form in a Circular Slab or Dome
Authors: Karam Chand Gupta
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When steel reinforcement is placed in mesh form in circular concrete slab at base or domes at top in case of over head service reservoir or any other structure, it is difficult to estimate/measure the total quantity of steel that would be needed or placed. For the purpose of calculating the total length of the steel bars, at present, the practice is – the length of each bar is measured and then added up. This is tiresome and time consuming process. I have derived a mathematics formula with the help of which we can calculate in one line the quantity of total steel that will be needed. This will not only make it easy and time saving but also avoids any error in making entries and calculations.Keywords: dome, mesh, slab, steel
Procedia PDF Downloads 681799 Application of Neuroscience in Aligning Instructional Design to Student Learning Style
Authors: Jayati Bhattacharjee
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Teaching is a very dynamic profession. Teaching Science is as much challenging as Learning the subject if not more. For instance teaching of Chemistry. From the introductory concepts of subatomic particles to atoms of elements and their symbols and further presenting the chemical equation and so forth is a challenge on both side of the equation Teaching Learning. This paper combines the Neuroscience of Learning and memory with the knowledge of Learning style (VAK) and presents an effective tool for the teacher to authenticate Learning. The model of ‘Working Memory’, the Visio-spatial sketchpad, the central executive and the phonological loop that transforms short-term memory to long term memory actually supports the psychological theory of Learning style i.e. Visual –Auditory-Kinesthetic. A closer examination of David Kolbe’s learning model suggests that learning requires abilities that are polar opposites, and that the learner must continually choose which set of learning abilities he or she will use in a specific learning situation. In grasping experience some of us perceive new information through experiencing the concrete, tangible, felt qualities of the world, relying on our senses and immersing ourselves in concrete reality. Others tend to perceive, grasp, or take hold of new information through symbolic representation or abstract conceptualization – thinking about, analyzing, or systematically planning, rather than using sensation as a guide. Similarly, in transforming or processing experience some of us tend to carefully watch others who are involved in the experience and reflect on what happens, while others choose to jump right in and start doing things. The watchers favor reflective observation, while the doers favor active experimentation. Any lesson plan based on the model of Prescriptive design: C+O=M (C: Instructional condition; O: Instructional Outcome; M: Instructional method). The desired outcome and conditions are independent variables whereas the instructional method is dependent hence can be planned and suited to maximize the learning outcome. The assessment for learning rather than of learning can encourage, build confidence and hope amongst the learners and go a long way to replace the anxiety and hopelessness that a student experiences while learning Science with a human touch in it. Application of this model has been tried in teaching chemistry to high school students as well as in workshops with teachers. The response received has proven the desirable results.Keywords: working memory model, learning style, prescriptive design, assessment for learning
Procedia PDF Downloads 351798 Intercultural Competencies as a Means to Rethink the Pedagogies of Diversity in Latin America
Authors: Marcelo Jose Cabarcas Ortega, Lissette Herrera, Juan Carlos Lemus Stave
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This work makes a rather theoretical reflection on a pedagogical response against the coloniality of knowledge and power. The purpose here is to reflect on the challenges and opportunities it opens up in the educational field. No doubt, ours derived in a more abstract than concrete reflection. The quest, nevertheless, to stimulate the interest in a non-violent, non-contemptuous education able to balance, improves and if necessary, transforms the relationships that have made it a space of privilege and exclusion. We all know the school has found itself in need of rethinking diversity while developing awareness of its own role in reproducing inequality. Intercultural education may provide an answer to that hurry when fostering critical awareness and dialogue.Keywords: decoloniality, coloniality of power, diversity, interculturality
Procedia PDF Downloads 233797 Utilization of Waste Glass Powder in Mortar
Authors: Suhaib Salahuddin Alzubair Suliman
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This paper examines the mechanical strength of different binders including pure ordinary Portland cement (OPC) and others having OPC supplemented by two maximum sizes of waste glass powder (GP) of 75-μm and 150μm. Chemical analysis of the GPs using PCEDX test analysis has revealed it silica (SiO2 ) content % is 86.883 and Calcium oxide (CaO) is 12.203%while there are traces of other impurities . Furthermore, the specific gravity of GP was measured. The experiments have been conducted on 63 specimens mortar made with standard sand with 20%,25%, and 30% of GP levels of substituting OPC. The specimens are tested at 3, 7 and 28 days for compressive strength and flexural strength. The specimens made with maximum GP size of 75-μm have outperformed the control OPC mortar at 28 days test age than size 150-μm at various replacement levels. In addition to that, the mechanical strengths were evaluated compressive strength and flexural strength tests were conducted for GPs. The findings from this study indicated that the mortars modified with GP 75μm and replacement ratio of 20% showed an improvement in compressive strength and flexural strength compared to the control mortar at the 28 days of curing with significant development between 7 and 28 days. Mortar with GP size 75-μm containing 30% & 20% replacement of cement have exhibited the highest flexural strength among all mortar mixtures. The improvement in the mechanical strength of the mortars modified with GP can be attributed to the pozzolanic property of GPs, which leads to a more densified microstructure and improved interfacial bonding between sand and cement paste matrix in mortars.Keywords: glass powder, pozzolana, compressive strength, flexural strength, mortar
Procedia PDF Downloads 70796 Practical Application of Simulation of Business Processes
Authors: Markéta Gregušová, Vladimíra Schindlerová, Ivana Šajdlerová, Petr Mohyla, Jan Kedroň
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Company managers are always looking for more and more opportunities to succeed in today's fiercely competitive market. To maintain your place among the successful companies on the market today or to come up with a revolutionary business idea is much more difficult than before. Each new or improved method, tool, or approach that can improve the functioning of business processes or even of the entire system is worth checking and verification. The use of simulation in the design of manufacturing systems and their management in practice is one of the ways without increased risk, which makes it possible to find the optimal parameters of manufacturing processes and systems. The paper presents an example of use of simulation for solution of the bottleneck problem in the concrete company.Keywords: practical applications, business processes, systems, simulation
Procedia PDF Downloads 543795 Building Bridges on Roads With Major Constructions
Authors: Mohamed Zaidour
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In this summary, we are going to look in brief at the bridges and their building and construction on most roads and we have followed a simple method to explain each field clearly because the geographical and climatic diversity of an area leads to different methods and types of roads and installation engineering in other areas In mountain areas we need to build retaining walls in areas of rain. It needs to construct ferries to discharge water from roads in areas of temporary or permanent rivers. There is a need to build bridges and construct road installations in the process of collecting the necessary information, such as soil type. This information needs it, engineer, when designing the constructor and in this section, we will identify the types and methods of calculation bridge columns rules phrases the walls are chock.Keywords: bridges, buildings, concrete, constructions, roads
Procedia PDF Downloads 119794 Correlations Between Electrical Resistivity and Some Properties of Clayey Soils
Authors: F. A. Hassona, M. M. Abu-Heleika, M. A. Hassan, A. E. Sidhom
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Application of electrical measurements to evaluate engineering properties of soils has gained a wide, promising field of research in recent years. So, understanding of the relation between in-situ electrical resistivity of clay soil, and their mechanical and physical properties consider a promising field of research. This would assist in introducing a new technique for the determination of soil properties based on electrical resistivity. In this work soil physical and mechanical properties of clayey soil have been determined by experimental tests and correlated with the in-situ electrical resistivity. The research program was conducted through measuring fifteen vertical electrical sounding stations along with fifteen selected boreholes. These samples were analyzed and subjected to experimental tests such as physical tests namely bulk density, water content, specific gravity, and grain size distribution, and Attereberg limits tests. Mechanical test was also conducted such as direct shear test. The electrical resistivity data were interpreted and correlated with each one of the measured experimental parameters. Based on this study mathematical relations were extracted and discussed. These results exhibit an excellent match with the results reported in the literature. This study demonstrates the utility of the developed methodology for determining the mechanical properties of soils easily and rapidly depending on their electrical resistivity measurements.Keywords: electrical resistivity, clayey soil, physical properties, shear properties
Procedia PDF Downloads 297793 A Study on the Improvement of the Bond Performance of Polypropylene Macro Fiber according to Longitudinal Shape Change
Authors: Sung-yong Choi, Woo-tai Jung, Young-hwan Park
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This study intends to improve the bond performance of the polypropylene fiber used as reinforcing fiber for concrete by changing its shape into double crimped type through the enhancement its fabrication process. The bond performance of such double crimped fiber is evaluated by applying the JCI SF-8 (dog-bone shape) testing method. The test results reveal that the double crimped fiber develops bond performance improved by more than 19% compared to the conventional crimped type fiber.Keywords: Bond, Polypropylene, fiber reinforcement, macro fiber, shape change
Procedia PDF Downloads 462792 Synthesis of Magnesium Oxide in Spinning Disk Reactor and Its Applications in Cycloaddition of Carbon Dioxide to Epoxides
Authors: Tzu-Wen Liu, Yi-Feng Lin, Yu-Shao Chen
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CO_2 is believed to be partly responsible for changes to the global climates. Carbon capture and storage (CCS) is one way to reduce carbon dioxide emissions in the past. Recently, how to convert the captured CO_2 into fine chemicals gets lots of attention owing to reducing carbon dioxide emissions and providing greener feedstock for the chemicals industry. A variety of products can be manufactured from carbon dioxide and the most attractive products are cyclic carbonates. Therefore, the kind of catalyst plays an important role in cycloaddition of carbon dioxide to epoxides. Magnesium oxide can be an efficiency heterogeneous catalyst for the cycloaddition of carbon dioxide to epoxides because magnesium oxide has both acid and base active sites and can provide the adsorption of carbon dioxide, promoting ring-opening reaction. Spinning disk reactor (SDR) is one of the device of high-gravity technique and has successfully used for synthesis of nanoparticles by precipitation methods because of the high mass transfer rate. Synthesis of nanoparticles in SDR has advantages of low energy consumption and easy to scale up. The aim of this research is to synthesize magnesium hydroxide nanoparticles in SDR as precursors for magnesium oxide. Experimental results showed that the calcination temperature of magnesium hydroxide to magnesium oxide, and the pressure and temperature of cycloaddition reaction had significantly effect on the conversion and selectivity of the reaction.Keywords: magnesium oxide, catalyst, cycloaddition, spinning disk reactor, carbon dioxide
Procedia PDF Downloads 296791 Derivation of Technology Element for Automation in Table Formwork in a Tall Building Construction
Authors: Junehyuck Lee, Dongmin Lee, Hunhee Cho, Kyung-In Kang
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A table formwork method has recently been widely applied in reinforced concrete structures in a tall building construction to improve safety and productivity. However, this method still depended mainly on manpower. Therefore, this study aimed at derivation of technology element to apply the automation in table formwork in a tall building construction. These results will contribute to improve productivity and labor saving in table formwork in tall building construction.Keywords: table form, tall building, automation, productivity
Procedia PDF Downloads 400790 Changing Behaviour in the Digital Era: A Concrete Use Case from the Domain of Health
Authors: Francesca Spagnoli, Shenja van der Graaf, Pieter Ballon
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Humans do not behave rationally. We are emotional, easily influenced by others, as well as by our context. The study of human behaviour became a supreme endeavour within many academic disciplines, including economics, sociology, and clinical and social psychology. Understanding what motivates humans and triggers them to perform certain activities, and what it takes to change their behaviour, is central both for researchers and companies, as well as policy makers to implement efficient public policies. While numerous theoretical approaches for diverse domains such as health, retail, environment have been developed, the methodological models guiding the evaluation of such research have reached for a long time their limits. Within this context, digitisation, the Information and communication technologies (ICT) and wearable, the Internet of Things (IoT) connecting networks of devices, and new possibilities to collect and analyse massive amounts of data made it possible to study behaviour from a realistic perspective, as never before. Digital technologies make it possible to (1) capture data in real-life settings, (2) regain control over data by capturing the context of behaviour, and (3) analyse huge set of information through continuous measurement. Within this complex context, this paper describes a new framework for initiating behavioural change, capitalising on the digital developments in applied research projects and applicable both to academia, enterprises and policy makers. By applying this model, behavioural research can be conducted to address the issues of different domains, such as mobility, environment, health or media. The Modular Behavioural Analysis Approach (MBAA) is here described and firstly validated through a concrete use case within the domain of health. The results gathered have proven that disclosing information about health in connection with the use of digital apps for health, can be a leverage for changing behaviour, but it is only a first component requiring further follow-up actions. To this end, a clear definition of different 'behavioural profiles', towards which addressing several typologies of interventions, it is essential to effectively enable behavioural change. In the refined version of the MBAA a strong focus will rely on defining a methodology for shaping 'behavioural profiles' and related interventions, as well as the evaluation of side-effects on the creation of new business models and sustainability plans.Keywords: behavioural change, framework, health, nudging, sustainability
Procedia PDF Downloads 221789 Aquatic Intervention Research for Children with Autism Spectrum Disorders
Authors: Mehmet Yanardag, Ilker Yilmaz
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Children with autism spectrum disorders (ASD) enjoy and success the aquatic-based exercise and play skills in a pool instead of land-based exercise in a gym. Some authors also observed that many children with ASD experience more success in attaining movement skills in aquatic environment. Properties of the water and hydrodynamic principles cause buoyancy of the water and decrease effects of gravity and it leads to allow a child to practice important aquatic skills with limited motor skills. Also, some authors experience that parents liked the effects of the aquatic intervention program on children with ASD such as improving motor performance, movement capacity and learning basic swimming skills. The purpose of this study was to investigate the effects of aquatic exercise training on water orientation and underwater working capacity were measured in the pool. This study included in four male children between 5 and 7 years old with ASD and 6.25±0.5 years old. Aquatic exercise skills were applied by using one of the error less teaching which is called the 'most to least prompt' procedure during 12-week, three times a week and 60 minutes a day. The findings of this study indicated that there were improvements test results both water orientation skill and underwater working capacity of children with ASD after 12-weeks exercise training. It was seen that the aquatic exercise intervention would be affected to improve working capacity and orientation skills with the special education approaches applying children with ASD in multidisciplinary team-works.Keywords: aquatic, autism, orientation, ASD, children
Procedia PDF Downloads 432788 Optimal Sliding Mode Controller for Knee Flexion during Walking
Authors: Gabriel Sitler, Yousef Sardahi, Asad Salem
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This paper presents an optimal and robust sliding mode controller (SMC) to regulate the position of the knee joint angle for patients suffering from knee injuries. The controller imitates the role of active orthoses that produce the joint torques required to overcome gravity and loading forces and regain natural human movements. To this end, a mathematical model of the shank, the lower part of the leg, is derived first and then used for the control system design and computer simulations. The design of the controller is carried out in optimal and multi-objective settings. Four objectives are considered: minimization of the control effort and tracking error; and maximization of the control signal smoothness and closed-loop system’s speed of response. Optimal solutions in terms of the Pareto set and its image, the Pareto front, are obtained. The results show that there are trade-offs among the design objectives and many optimal solutions from which the decision-maker can choose to implement. Also, computer simulations conducted at different points from the Pareto set and assuming knee squat movement demonstrate competing relationships among the design goals. In addition, the proposed control algorithm shows robustness in tracking a standard gait signal when accounting for uncertainty in the shank’s parameters.Keywords: optimal control, multi-objective optimization, sliding mode control, wearable knee exoskeletons
Procedia PDF Downloads 82787 Integrating Virtual Reality and Building Information Model-Based Quantity Takeoffs for Supporting Construction Management
Authors: Chin-Yu Lin, Kun-Chi Wang, Shih-Hsu Wang, Wei-Chih Wang
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A construction superintendent needs to know not only the amount of quantities of cost items or materials completed to develop a daily report or calculate the daily progress (earned value) in each day, but also the amount of quantities of materials (e.g., reinforced steel and concrete) to be ordered (or moved into the jobsite) for performing the in-progress or ready-to-start construction activities (e.g., erection of reinforced steel and concrete pouring). These daily construction management tasks require great effort in extracting accurate quantities in a short time (usually must be completed right before getting off work every day). As a result, most superintendents can only provide these quantity data based on either what they see on the site (high inaccuracy) or the extraction of quantities from two-dimension (2D) construction drawings (high time consumption). Hence, the current practice of providing the amount of quantity data completed in each day needs improvement in terms of more accuracy and efficiency. Recently, a three-dimension (3D)-based building information model (BIM) technique has been widely applied to support construction quantity takeoffs (QTO) process. The capability of virtual reality (VR) allows to view a building from the first person's viewpoint. Thus, this study proposes an innovative system by integrating VR (using 'Unity') and BIM (using 'Revit') to extract quantities to support the above daily construction management tasks. The use of VR allows a system user to be present in a virtual building to more objectively assess the construction progress in the office. This VR- and BIM-based system is also facilitated by an integrated database (consisting of the information and data associated with the BIM model, QTO, and costs). In each day, a superintendent can work through a BIM-based virtual building to quickly identify (via a developed VR shooting function) the building components (or objects) that are in-progress or finished in the jobsite. And he then specifies a percentage (e.g., 20%, 50% or 100%) of completion of each identified building object based on his observation on the jobsite. Next, the system will generate the completed quantities that day by multiplying the specified percentage by the full quantities of the cost items (or materials) associated with the identified object. A building construction project located in northern Taiwan is used as a case study to test the benefits (i.e., accuracy and efficiency) of the proposed system in quantity extraction for supporting the development of daily reports and the orders of construction materials.Keywords: building information model, construction management, quantity takeoffs, virtual reality
Procedia PDF Downloads 132786 Co-Authorship Networks of Scientific Collaboration
Authors: Juha Kettunen
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This study analyzes collaborative and networked academic authorship in higher education. The literature review shows evidence that single authorship has made a gradual paradigm shift to joint authorship. The empirical evidence from the Turku University of Applied Sciences indicates that collaborative authorship has notably increased in the last few years. Co-authorship has extended outside the institution to other domestic and international academic organizations. Co-authorship not only increase the merits of academic scholars but builds and maintains networks of research and development. The results of this study help the authors, editors and partners of research and development projects to have a more concrete understanding of how co-authorship has developed and spread beyond higher education institutions.Keywords: co-authorship, social networking, higher education, research and development
Procedia PDF Downloads 242785 Probabilistic Robustness Assessment of Structures under Sudden Column-Loss Scenario
Authors: Ali Y Al-Attraqchi, P. Rajeev, M. Javad Hashemi, Riadh Al-Mahaidi
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This paper presents a probabilistic incremental dynamic analysis (IDA) of a full reinforced concrete building subjected to column loss scenario for the assessment of progressive collapse. The IDA is chosen to explicitly account for uncertainties in loads and system capacity. Fragility curves are developed to predict the probability of progressive collapse given the loss of one or more columns. At a broader scale, it will also provide critical information needed to support the development of a new generation of design codes that attempt to explicitly quantify structural robustness.Keywords: fire, nonlinear incremental dynamic analysis, progressive collapse, structural engineering
Procedia PDF Downloads 266784 Experimental Investigation of The Influence of Cement on Soil-Municipal Solid Waste Incineration Fly ash Mix Properties
Authors: Gehan Aouf, Diala Tabbal, Abd El Rahim Sabsabi, Rashad Aouf
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The aim of this study is to assess the viability of utilizing Municipal Solid Waste Incineration Fly Ash (MSWIFA) with Ordinary Portland cement as soil reinforcement materials for geotechnical engineering applications. A detailed experimental program is carried out, followed by analysis of results. Soil samples were prepared by adding Cement to MSWIFA-soil mix at different percentages. Then, a series of laboratory tests were performed, namely: Sieve analysis, Atterberg limits tests, Unconfined compression test, and Proctor tests. A parametric study is conducted to investigate the effect of adding the cement at different percentages on the unconfined compression strength, maximum dry density, and optimum moisture content of clayey soil-MSWIFA The variation of contents of admixtures were 10%, 20%, and 30% for MSWIFA by dry total weight of soil and 10%, 15%, and 20% for Portland cement by dry total weight of the mix. The test results reveal that adding MSWIFA to the soil up to 20% increased the MDD of the mixture and decreased the OMC, then an opposite trend for results were found when the percentage of MSWIFA exceeds 20%. This is due to the low specific gravity of MSWIFA and to the greater water absorption of MSWIFA. The laboratory tests also indicate that the UCS values were found to be increased for all the mixtures with curing periods of 7, 14, and 28 days. It is also observed that the cement increased the strength of the finished product of the mix of soil and MSWIFA.Keywords: clayey soil, cement, MSWIFA, unconfined compression strength
Procedia PDF Downloads 131783 Finite Volume Method for Flow Prediction Using Unstructured Meshes
Authors: Juhee Lee, Yongjun Lee
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In designing a low-energy-consuming buildings, the heat transfer through a large glass or wall becomes critical. Multiple layers of the window glasses and walls are employed for the high insulation. The gravity driven air flow between window glasses or wall layers is a natural heat convection phenomenon being a key of the heat transfer. For the first step of the natural heat transfer analysis, in this study the development and application of a finite volume method for the numerical computation of viscous incompressible flows is presented. It will become a part of the natural convection analysis with high-order scheme, multi-grid method, and dual-time step in the future. A finite volume method based on a fully-implicit second-order is used to discretize and solve the fluid flow on unstructured grids composed of arbitrary-shaped cells. The integrations of the governing equation are discretised in the finite volume manner using a collocated arrangement of variables. The convergence of the SIMPLE segregated algorithm for the solution of the coupled nonlinear algebraic equations is accelerated by using a sparse matrix solver such as BiCGSTAB. The method used in the present study is verified by applying it to some flows for which either the numerical solution is known or the solution can be obtained using another numerical technique available in the other researches. The accuracy of the method is assessed through the grid refinement.Keywords: finite volume method, fluid flow, laminar flow, unstructured grid
Procedia PDF Downloads 286782 Numerical Investigation of Nanofluid Based Thermosyphon System
Authors: Kiran Kumar K., Ramesh Babu Bejjam, Atul Najan
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A thermosyphon system is a heat transfer loop which operates on the basis of gravity and buoyancy forces. It guarantees a good reliability and low maintenance cost as it does not involve any mechanical pump. Therefore it can be used in many industrial applications such as refrigeration and air conditioning, electronic cooling, nuclear reactors, geothermal heat extraction, etc. But flow instabilities and loop configuration are the major problems in this system. Several previous researchers studied that stabilities can be suppressed by using nanofluids as loop fluid. In the present study a rectangular thermosyphon loop with end heat exchangers are considered for the study. This configuration is more appropriate for many practical applications such as solar water heater, geothermal heat extraction, etc. In the present work, steady-state analysis is carried out on thermosyphon loop with parallel flow coaxial heat exchangers at heat source and heat sink. In this loop nano fluid is considered as the loop fluid and water is considered as the external fluid in both hot and cold heat exchangers. For this analysis one-dimensional homogeneous model is developed. In this model, conservation equations like conservation of mass, momentum, energy are discretized using finite difference method. A computer code is written in MATLAB to simulate the flow in thermosyphon loop. A comparison in terms of heat transfer is made between water and nano fluid as working fluids in the loop.Keywords: heat exchanger, heat transfer, nanofluid, thermosyphon loop
Procedia PDF Downloads 477781 Design Optimization of the Primary Containment Building of a Pressurized Water Reactor
Authors: M. Hossain, A. H. Khan, M. A. R. Sarkar
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Primary containment structure is one of the five safety layers of a nuclear facility which is needed to be designed in such a manner that it can withstand the pressure and excessive radioactivity during accidental situations. It is also necessary to ensure minimization of cost with maximum possible safety in order to make the design economically feasible and attractive. This paper attempts to identify the optimum design conditions for primary containment structure considering both mechanical and radiation safety keeping the economic aspects in mind. This work takes advantage of commercial simulation software to identify the suitable conditions without the requirement of costly experiments. Generated data may be helpful for further studies.Keywords: PWR, concrete containment, finite element approach, neutron attenuation, Von Mises stress
Procedia PDF Downloads 187780 Contribution of Algerians Local Materials on the Compressive Strengths of Concrete: Experimental and Numerical Study
Authors: Mohamed Lyes Kamel Khouadjia, Bouzidi Mezghiche
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The evolution in the civil engineering and carried out more consumption of aggregates and particularly the sand. Due to the depletion of natural reserves of sand, it is necessary to focus on the use of local materials such as crushed sand, river sand and dune sand, mineral additions. The aim of this work is to improve the state of knowledge on the compressive strengths of crushed sands with several mixtures (dune sand, river sand, pozzolan, and slag). The obtained results were compared with numerical results obtained with the software Béton Lab Pro 3.Keywords: crushed sand, river sand, dune sand, pouzzolan, slag, compressive strengths, Béton Lab Pro 3
Procedia PDF Downloads 325779 Curative Effect of Blumea lacera Leaves on Experimental Haemorrhoids in Rats
Authors: Priyanka Sharma, Tarkewshwar Dubey, Hemalatha Siva
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Hemorrhoids are one of the most common anorectal diseases around the world. Severalfactors are involved in causing hemorrhoids including irregularbowel function (constipation, diarrhea), exercise, gravity, low fiberdiet, pregnancy, obesity, high abdominal pressure, prolongedsitting, genetic factors, and aging. Pain, bleeding, itching,swelling and anal discharge are the symptoms of the disease. Due to limitedmodern pharmacotherapeutic options available for treatment, theherbal medicines remain the choice of therapy. Blumea lacera (Burm f.) DC. belonging to the Asteraceae family is a common plain land weed of Bangladesh. Traditionally it has been used for treatment of hemorrhoids.Considering the above fact, present study was aimed to validate the ethnomedicinal use of B. lacera leaves on experimental hemorrhoids in rats. The anti-hemorrhoid activity was performed by using croton oil induced rat models. The parameters studied were assessment of TNF-α and IL-6, Evans blue exudation, macroscopic severity score, recto-anal coefficient, histomorphological scores. Also, in vivo antioxidant parameters and histopathological studies were also performed. All paramaters exhibited significant anti-hemorrhoid activity. Moreover ethanolic extract of B. lacera (EBL) leaves 400mg/kg showed ameliorative effect oncroton oil induced hemorrhoids.In conclusion, EBL exhibitedbeneficial effect on croton oil- induced hemorrhoids and validates its ethnomedicinal use in treatment of piles.Keywords: haemorrhoids, IL-6, piles, TNF-α
Procedia PDF Downloads 294778 Design and Production of Thin-Walled UHPFRC Footbridge
Authors: P. Tej, P. Kněž, M. Blank
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The paper presents design and production of thin-walled U-profile footbridge made of UHPFRC. The main structure of the bridge is one prefabricated shell structure made of UHPFRC with dispersed steel fibers without any conventional reinforcement. The span of the bridge structure is 10 m and the clear width of 1.5 m. The thickness of the UHPFRC shell structure oscillated in an interval of 30-45 mm. Several calculations were made during the bridge design and compared with the experiments. For the purpose of verifying the calculations, a segment of 1.5 m was first produced, followed by the whole footbridge for testing. After the load tests were done, the design was optimized to cast the final footbridge.Keywords: footbridge, non-linear analysis, shell structure, UHPFRC, Ultra-High Performance Fibre Reinforced Concrete
Procedia PDF Downloads 232777 Use of Recycled PVB as a Protection against Carbonation
Authors: Michael Tupý, Vít Petránek
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The paper is focused on testing of the poly(vinyl butyral) (PVB) layer which had the function of a CO2 insulating protection against concrete and mortar carbonation. The barrier efficiency of PVB was verified by the measurement of diffusion characteristics. Two different types of PVB were tested; original extruded PVB sheet and PVB sheet made from PVB dispersion which was obtained from recycled windshields. The work deals with the testing CO2 diffusion when polymer sheets were exposed to a CO2 atmosphere (10% v/v CO2) with 0% RH. The excellent barrier capability against CO2 permeability of original and also recycled types of PVB layers was observed. This application of PVB waste can bring advantageous use in civil engineering and significant environmental contribution.Keywords: windshield, poly(vinyl butyral), mortar, diffusion, carbonatation, polymer waste
Procedia PDF Downloads 423776 Design of Reinforced Concrete (RC) Walls Considering Shear Amplification by Nonlinear Dynamic Behavior
Authors: Sunghyun Kim, Hong-Gun Park
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In the performance-based design (PBD), by using the nonlinear dynamic analysis (NDA), the actual performance of the structure is evaluated. Unlike frame structures, in the wall structures, base shear force which is resulted from the NDA, is greatly amplified than that from the elastic analysis. This shear amplifying effect causes repeated designs which make designer difficult to apply the PBD. Therefore, in this paper, factors which affect shear amplification were studied. For the 20-story wall model, the NDA was performed. From the analysis results, the base shear amplification factor was proposed.Keywords: performance based design, shear amplification factor, nonlinear dynamic analysis, RC shear wall
Procedia PDF Downloads 379775 Relationship between Personality Traits and Postural Stability among Czech Military Combat Troops
Authors: K. Rusnakova, D. Gerych, M. Stehlik
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Postural stability is a complex process involving actions of biomechanical, motor, sensory and central nervous system components. Numerous joint systems, muscles involved, the complexity of sporting movements and situations require perfect coordination of the body's movement patterns. To adapt to a constantly changing situation in such a dynamic environment as physical performance, optimal input of information from visual, vestibular and somatosensory sensors are needed. Combat soldiers are required to perform physically and mentally demanding tasks in adverse conditions, and poor postural stability has been identified as a risk factor for lower extremity musculoskeletal injury. The aim of this study is to investigate whether some personality traits are related to the performance of static postural stability among soldiers of combat troops. NEO personality inventory (NEO-PI-R) was used to identify personality traits and the Nintendo Wii Balance Board was used to assess static postural stability of soldiers. Postural stability performance was assessed by changes in center of pressure (CoP) and center of gravity (CoG). A posturographic test was performed for 60 s with eyes opened during quiet upright standing. The results showed that facets of neuroticism and conscientiousness personality traits were significantly correlated with measured parameters of CoP and CoG. This study can help for better understanding the relationship between personality traits and static postural stability. The results can be used to optimize the training process at the individual level.Keywords: neuroticism, conscientiousness, postural stability, combat troops
Procedia PDF Downloads 142774 Micro- and Nanoparticle Transport and Deposition in Elliptic Obstructed Channels by Lattice Boltzmann Method
Authors: Salman Piri
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In this study, a two-dimensional lattice Boltzmann method (LBM) was considered for the numerical simulation of fluid flow in a channel. Also, the Lagrangian method was used for particle tracking in one-way coupling. Three hundred spherical particles with specific diameters were released in the channel entry and an elliptical object was placed in the channel for flow obstruction. The effect of gravity, the drag force, the Saffman lift and the Brownian forces were evaluated in the particle motion trajectories. Also, the effect of the geometrical parameter, ellipse aspect ratio, and the flow characteristic or Reynolds number was surveyed for the transport and deposition of particles. Moreover, the influence of particle diameter between 0.01 and 10 µm was investigated. Results indicated that in small Reynolds, more inertial and gravitational trapping occurred on the obstacle surface for particles with larger diameters. Whereas, for nano-particles, influenced by Brownian diffusion and vortices behind the obstacle, the inertial and gravitational mechanisms were insignificant and diffusion was the dominant deposition mechanism. In addition, in Reynolds numbers larger than 400, there was no significant difference between the deposition of finer and larger particles. Also, in higher aspect ratios of the ellipse, more inertial trapping occurred for particles of larger diameter (10 micrometers), while in lower cases, interception and gravitational mechanisms were dominant.Keywords: ellipse aspect elito, particle tracking diffusion, lattice boltzman method, larangain particle tracking
Procedia PDF Downloads 79773 Pushover Analysis of Masonry Infilled Reinforced Concrete Frames for Performance Based Design for near Field Earthquakes
Authors: Alok Madan, Ashok Gupta, Arshad K. Hashmi
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Non-linear dynamic time history analysis is considered as the most advanced and comprehensive analytical method for evaluating the seismic response and performance of multi-degree-of-freedom building structures under the influence of earthquake ground motions. However, effective and accurate application of the method requires the implementation of advanced hysteretic constitutive models of the various structural components including masonry infill panels. Sophisticated computational research tools that incorporate realistic hysteresis models for non-linear dynamic time-history analysis are not popular among the professional engineers as they are not only difficult to access but also complex and time-consuming to use. And, commercial computer programs for structural analysis and design that are acceptable to practicing engineers do not generally integrate advanced hysteretic models which can accurately simulate the hysteresis behavior of structural elements with a realistic representation of strength degradation, stiffness deterioration, energy dissipation and ‘pinching’ under cyclic load reversals in the inelastic range of behavior. In this scenario, push-over or non-linear static analysis methods have gained significant popularity, as they can be employed to assess the seismic performance of building structures while avoiding the complexities and difficulties associated with non-linear dynamic time-history analysis. “Push-over” or non-linear static analysis offers a practical and efficient alternative to non-linear dynamic time-history analysis for rationally evaluating the seismic demands. The present paper is based on the analytical investigation of the effect of distribution of masonry infill panels over the elevation of planar masonry infilled reinforced concrete (R/C) frames on the seismic demands using the capacity spectrum procedures implementing nonlinear static analysis (pushover analysis) in conjunction with the response spectrum concept. An important objective of the present study is to numerically evaluate the adequacy of the capacity spectrum method using pushover analysis for performance based design of masonry infilled R/C frames for near-field earthquake ground motions.Keywords: nonlinear analysis, capacity spectrum method, response spectrum, seismic demand, near-field earthquakes
Procedia PDF Downloads 404