Search results for: maximum energy

Authors: Rakesh Mishra, Rajni Singh, Mukunda Upadhyay

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Since the last few decades, the prima facie of development has shifted towards the working population in India. There has been a paradigm shift in the development approach with the realization that the present demographic dividend has to be harnessed for sustainable development. Rapid urbanization and improved socioeconomic characteristics experienced within its territory has catalyzed various forms of migration into it, resulting in massive transference of workforce between its states. Workforce in any country plays a very crucial role in deciding development of both the places, from where they have out-migrated and the place they are residing currently. In India, people are found to be migrating from relatively less developed states to a well urbanized and developed state for satisfying their neediness. Linking migration to HDI at place of destination, the regression coefficient (β ̂) shows affirmative association between them, because higher the HDI of the place would be, higher would be chance of earning and hence likeliness of the migrants would be more to choose that place as a new destination and vice versa. So the push factor is compromised by the cost of rearing and provides negative impulse on the in migrants letting down their numbers to metro cities or megacities of the states but increasing their mobility to the suburban areas and vice versa. The main objective of the study is to check the role of migration in deciding the dividend of the place of destination as well as people at the place of their usual residence with special focus to highly urban states in India. Idealized scenario of Indian migrants refers to some new theories in making. On analyzing the demographic dividend of the places we got to know that Uttar Pradesh provides maximum dividend to Maharashtra, West Bengal and Delhi, and the demographic divided of migrants are quite comparable to the native’s shares in the demographic dividend in these places. On analyzing the data from National Sample Survey 64th round and Census of India-2001, we have observed that for males in rural areas, the share of unemployed person declined by 9 percentage points (from 45% before migration to 36 % after migration) and for females in rural areas the decline was nearly 12 percentage points (from 79% before migration to 67% after migration. It has been observed that the shares of unemployed males in both rural and urban areas, which were significant before migration, got reduced after migration while the share of unemployed females in the rural as well as in the urban areas remained almost negligible both for before and after migration. So increase in the number of employed after migration provides an indication of changes in the associated cofactors like health and education of the place of destination and arithmetically to the place from where they have migrated out. This paper presents the evidence on the patterns of prevailing migration dynamics and corresponding demographic benefits in India and its states, examines trends and effects, and discusses plausible explanations.

Keywords: migration, demographic shift, human development index, multilevel analysis

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Authors: Mateusz Paszko, Ksenia Siadkowska

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Due to the low-altitude and relatively low-speed flight, helicopters are easy targets for actual combat assets e.g. infrared-guided missiles. Current techniques aim to increase the combat effectiveness of the military helicopters. Protection of the helicopter in flight from early detection, tracking and finally destruction can be realized in many ways. One of them is cooling hot exhaust gasses, emitting from the engines to the atmosphere in special heat exchangers. Nowadays, this process is realized in ejective coolers, where strong heat and momentum exchange between hot exhaust gases and cold air ejected from atmosphere takes place. Flow effects of air, exhaust gases; mixture of those two and the heat transfer between cold air and hot exhaust gases are given by differential equations of: Mass transportation–flow continuity, ejection of cold air through expanding exhaust gasses, conservation of momentum, energy and physical relationship equations. Calculation of those processes in ejective cooler by means of classic mathematical analysis is extremely hard or even impossible. Because of this, it is necessary to apply the numeric approach with modern, numeric computer programs. The paper discussed the general usability of the Computational Fluid Dynamics (CFD) in a process of projecting the ejective exhaust gases cooler cooperating with helicopter turbine engine. In this work, the CFD calculations have been performed for ejective-based cooler cooperating with the PA W3 helicopter’s engines.

Keywords: aviation, CFD analysis, ejective-cooler, helicopter techniques

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Authors: Oluwole Durodolu

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The rationale for this study is to explore the adaptive strategy that librarians adopt in performing night shifts in a mega-city like Lagos state. Maslach Burnout Theory would be used to measure the three proportions of burnout in understanding emotional exhaustion, depersonalisation, and individual accomplishment to scrutinise job-related burnout syndrome allied with longstanding, unsolved stress. The qualitative methodology guided by a phenomenological research paradigm, which is an approach that focuses on the commonality of real-life experience in a particular group, would be used, focus group discussion adopted as a method of data collection from library staff who are involved in night-shift. The participant for the focus group discussion would be selected using a convenience sampling technique in which staff at the cataloguing unit would be included in the sample because of the representative characteristics of the unit. This would be done to enable readers to understand phenomena as it is reasonable than from a remote perspective. The exploratory interviews which will be in focus group method to shed light on issues relating to security, housing, transportation, budgeting, energy supply, employee duties, time management, information access, and sustaining professional levels of service and how all these variables affect the productivity of all the 149 library staff and their work-life balance.

Keywords: nightshift, work-life balance, mega-city, academic library, Maslach Burnout Theory, Lagos State, University of Lagos

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Authors: Mario A. Blanco, Nicholas Burkhardt

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An important problem in satellite communication systems which operate in the Ka and EHF frequency bands consists of the overall degradation in link performance of mobile terminals due to various types of degradations in the link/channel, such as fading, blockage of the link to the satellite (especially in urban environments), intentional as well as other types of interference, etc. In this paper, we focus primarily on the interference problem, and we develop a very efficient and cost-effective solution based on the use of fountain codes. We first introduce a satellite communications (SATCOM) terminal uplink interference channel model that is classically used against communication systems that use spread-spectrum waveforms. We then consider the use of fountain codes, with focus on Raptor codes, as our main mitigation technique to combat the degradation in link/receiver performance due to the interference signal. The performance of the receiver is obtained in terms of average probability of bit and message error rate as a function of bit energy-to-noise density ratio, Eb/N0, and other parameters of interest, via a combination of analysis and computer simulations, and we show that the use of fountain codes is extremely effective in overcoming the effects of intentional interference on the performance of the receiver and associated communication links. We then show this technique can be extended to mitigate other types of SATCOM channel degradations, such as those caused by channel fading, shadowing, and hard-blockage of the uplink signal.

Keywords: SATCOM, interference mitigation, fountain codes, turbo codes, cross-layer

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Authors: Atousa Khodadadyan, Ali Rostami

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The objective of off-site construction manufacturing is to utilise the workforce and machinery in a controlled environment without external interference for higher productivity and quality. The usage of prefabricated components can save up to 14% of the total energy consumption in comparison with the equivalent number of cast-in-place ones. Despite the benefits of prefabrication construction, its current project practices encompass technical and managerial issues. Building design, precast components’ production, logistics, and prefabrication installation processes are still mostly discontinued and fragmented. Furthermore, collaboration among prefabrication manufacturers, transportation parties, and on-site assemblers rely on real-time information such as the status of precast components, delivery progress, and the location of components. From the technical point of view, in this industry, geometric variability is still prevalent, which can be caused during the transportation or production of components. These issues indicate that there are still many aspects of prefabricated construction that can be developed using disruptive technologies. Practical real-time risk analysis can be used to address these issues as well as the management of safety, quality, and construction environment issues. On the other hand, the lack of research about risk assessment and the absence of standards and tools hinder risk management modeling in prefabricated construction. It is essential to note that no risk management standard has been established explicitly for prefabricated construction projects, and most software packages do not provide tailor-made functions for this type of projects.

Keywords: project risk management, risk analysis, risk modelling, prefabricated construction projects

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Authors: K. Uyanga, W. Daoud

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Hydrogels have attracted much academic and industrial attention due to their unique properties and potential biomedical and non-biomedical applications. Limitations on extending their applications have resulted from the synthesis of hydrogels using toxic materials and complex irreproducible processing techniques. In order to promote environmental sustainability, hydrogel efficiency, and wider application, this study focused on the synthesis of composite hydrogels matrices from an edible non-toxic crosslinker-citric acid (CA) using a simple low energy processing method based on carboxymethyl cellulose (CMC) and chitosan (CSN) natural polymers. Composite hydrogels were developed by chemical crosslinking. The results demonstrated that CMC:2CSN:CA exhibited good performance properties and super-absorbency 21× its original weight. This makes it promising for biomedical applications such as chronic wound healing and regeneration, next generation skin substitute, in situ bone regeneration and cell delivery. On the other hand, CMC:CSN:CA exhibited durable well-structured internal network with minimum swelling degrees, water absorbency, excellent gel fraction, and infra-red reflectance. These properties make it a suitable composite hydrogel matrix for warming effect and controlled and efficient release of loaded materials. CMC:2CSN:CA and CMC:CSN:CA composite hydrogels developed also exhibited excellent chemical, morphological, and thermal properties.

Keywords: citric acid, fumaric acid, tartaric acid, zinc nitrate hexahydrate

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Authors: Mark T. Hanson, Alan T. Varughese

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Osteoporosis is a disease affecting bone quality which in turn can increase the risk of low energy fractures. Treatment of osteoporosis using Bisphosphonates has the beneficial effect of increasing bone mass while at the same time has been linked to the formation of atypical femoral fractures. This has led to the increased study of micro-fractures in bones of patients using Bisphosphonate treatment. One of the mechanics related issues which have been identified in this regard is the loss in stiffness of bones containing one or many micro-fractures. Different theories have been put forth using fracture mechanics to determine the effect of crack presence on elastic properties such as modulus. However, validation of these results in a deterministic way has not been forthcoming. The present analysis seeks to provide this deterministic evaluation of fracture’s effect on the elastic modulus. In particular, the effect of crack size, crack orientation and crack number on elastic modulus is investigated. In particular, the Finite Element method is used to explicitly determine the elastic modulus reduction caused by the presence of cracks in a representative volume element. Single cracks of various lengths and orientations are examined as well as cases of multiple cracks. Cracks in tension as well as under shear stress are considered. Although the focus is predominantly two-dimensional, some three-dimensional results are also presented. The results obtained show the explicit reduction in modulus caused by the parameters of crack size, orientation and number noted above. The present results allow the interpretation of the various theories which currently exist in the literature.

Keywords: cracks, elastic, fracture, modulus

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Authors: Samir Ranjbar, Nasrullah Istanekzai

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According to a report published in The Guardian, Kabul, the capital city of Afghanistan is the fifth fastest growing city in the world, whose population has increased fourfold since 2001 from 1.2 million to 4.8 million people. The main reason for this increment is identified as the return of Afghans migrated during the civil war. In addition to the return of immigrants, a steep economic growth due to foreign assistance in last decade creating lots of job opportunities in Kabul resulted in the attraction of individuals from the neighboring provinces as well. However, the development of urban facilities such as water supply system, housing transportation and waste management systems has yet to catch up with this rapid increase in population. Since Kabul city has developed traditionally and municipal governance had very limited capacity to implement municipal bylaws. As an unwanted consequence of this growth 70% of Kabul citizens contributed to developing informal settlement for which we can say that around three million people living in informally settled areas, lacking the very vital social and physical infrastructures of livelihood. This research focuses on a region with 30 ha area and 2100 people residents in the center of Kabul city. A comprehensive land readjustment concept plan has been formulated for this area. Through this concept plan, physical and social infrastructure has been demonstrated and analyzed. Findings of this paper propose a solution for the problems of this unplanned area in Kabul which is readjusting of unplanned area by a self-supporting process. This process does not need governmental budget and can be applied by government, private sectors and landowner associations. Furthermore, by implementing the Land Readjustment process, conceptual plans can be built for unplanned areas, maximum facilities can be brought to the residents’ urban life, improve the environment for the users’ benefit, promote the culture and sense of cooperation, participation and coexistence in the mind of people, improving the transport system, improvement in economic status (the value of land increases due to infrastructure availability and land legalization). In addition to all these benefits for the public, we can raise the revenue of government by collecting the taxes from landowners. This process is implemented in most of countries of the world, it was implemented for the first time in Germany and after that in most cities of Japan as well, and is known as one of the effective processes for infrastructural development. To sum up, the notable characteristic of the Land readjustment process is that it works on the concept of mutual interest in which both landowners and the government take advantage. However, in this process, the engagement of community is very important and without public cooperation, this process can face the failure.

Keywords: land readjustment, informal settlement, Kabul, Afghanistan

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Authors: Dinesh Pathaka, Tomas Wagnera, J. M. Nunzib

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We investigated blends of MdPVV.PCBM.AIS for photovoltaic application. AgInSe2 powder was synthesized by sealing and heating the stoichiometric constituents in evacuated quartz tube ampule. Fine grinded AIS powder was dispersed in MD-MOPVV and PCBM with and without surfactant. Different concentrations of these particles were suspended in the polymer solutions and spin casted onto ITO glass. Morphological studies have been performed by atomic force microscopy and optical microscopy. The blend layers were also investigated by various techniques like XRD, UV-VIS optical spectroscopy, AFM, PL, after a series of various optimizations with polymers/concentration/deposition/ suspension/surfactants etc. XRD investigation of blend layers shows clear evidence of AIS dispersion in polymers. Diode behavior and cell parameters also revealed it. Bulk heterojunction hybrid photovoltaic device Ag/MoO3/MdPVV.PCBM.AIS/ZnO/ITO was fabricated and tested with standard solar simulator and device characterization system. The best performance and photovoltaic parameters we obtained was an open-circuit voltage of about Voc 0.54 V and a photocurrent of Isc 117 micro A and an efficiency of 0.2 percent using a white light illumination intensity of 23 mW/cm2. Our results are encouraging for further research on the fourth generation inorganic organic hybrid bulk heterojunction photovoltaics for energy. More optimization with spinning rate/thickness/solvents/deposition rates for active layers etc. need to be explored for improved photovoltaic response of these bulk heterojunction devices.

Keywords: thin films, photovoltaic, hybrid systems, heterojunction

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Authors: M. K. Benhaoua, A. K. Singh, A. E. Benyamina, P. Boulet

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Mapping parallelized tasks of applications onto these MPSoCs can be done either at design time (static) or at run-time (dynamic). Static mapping strategies find the best placement of tasks at design-time, and hence, these are not suitable for dynamic workload and seem incapable of runtime resource management. The number of tasks or applications executing in MPSoC platform can exceed the available resources, requiring efficient run-time mapping strategies to meet these constraints. This paper describes a new Spiral Dynamic Task Mapping heuristic for mapping applications onto NoC-based Heterogeneous MPSoC. This heuristic is based on packing strategy and routing Algorithm proposed also in this paper. Heuristic try to map the tasks of an application in a clustering region to reduce the communication overhead between the communicating tasks. The heuristic proposed in this paper attempts to map the tasks of an application that are most related to each other in a spiral manner and to find the best possible path load that minimizes the communication overhead. In this context, we have realized a simulation environment for experimental evaluations to map applications with varying number of tasks onto an 8x8 NoC-based Heterogeneous MPSoCs platform, we demonstrate that the new mapping heuristics with the new modified dijkstra routing algorithm proposed are capable of reducing the total execution time and energy consumption of applications when compared to state-of-the-art run-time mapping heuristics reported in the literature.

Keywords: multiprocessor system on chip, MPSoC, network on chip, NoC, heterogeneous architectures, run-time mapping heuristics, routing algorithm

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Authors: Pattra Pukdeekiat, Siriluk Ruangrungrote

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This work was originated to precisely determine direct solar radiation by using atmospheric physics models since the accurate prediction of solar radiation is necessary and useful for solar energy applications including atmospheric research. The possible models and techniques for a calculation of regional direct solar radiation were challenging and compulsory for the case of unavailable instrumental measurement. The investigation was mathematically governed by six astronomical parameters i.e. declination (δ), hour angle (ω), solar time, solar zenith angle (θz), extraterrestrial radiation (Iso) and eccentricity (E0) along with two atmospheric parameters i.e. air mass (mr) and dew point temperature at Bangna meteorological station (13.67° N, 100.61° E) in Bangkok, Thailand. Analyses of five models of solar radiation determination with the assumption of clear sky were applied accompanied by three statistical tests: Mean Bias Difference (MBD), Root Mean Square Difference (RMSD) and Coefficient of determination (R2) in order to validate the accuracy of obtainable results. The calculated direct solar radiation was in a range of 491-505 Watt/m2 with relative percentage error 8.41% for winter and 532-540 Watt/m2 with relative percentage error 4.89% for summer 2014. Additionally, dataset of seven continuous days, representing both seasons were considered with the MBD, RMSD and R2 of -0.08, 0.25, 0.86 and -0.14, 0.35, 3.29, respectively, which belong to Kumar model for winter and CSR model for summer. In summary, the determination of direct solar radiation based on atmospheric models and empirical equations could advantageously provide immediate and reliable values of the solar components for any site in the region without a constraint of actual measurement.

Keywords: atmospheric physics models, astronomical parameters, atmospheric parameters, clear sky condition

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Authors: Hossein Edrisi

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To study the impact of the amount and volume of power of isolation transformer on the lamps in airfield Ground Lighting Systems. A test was conducted in Persian Gulf International Airport, This airport is situated in the south of Iran and it is one of the most cutting-edge airports, the same one that owns modern devices. Iran uses materials and auxiliary equipment which are made by ADB Company from Belgium. Airfield ground lighting (AGL) systems are responsible for providing visual issue to aircrafts and helicopters in the runways. In an AGL system a great deal of lamps are connected in serial circuits to each other and each ring has its individual constant current regulators (CCR), which through that provide energy to the lamps. Control of lamps is crucial for maintenance and operation in the AGL systems. Thanks to the Programmable Logic Controller (PLC) that is a cutting-edge technology can help the system to connect the elements from substations and ATC (TOWER). For this purpose, a test in real conditions of the airport done for all element that used in the airport such as isolation transformer in different power capacity and different consuming power and brightness of the lamps. The data were analyzed with Lux meter and Multimeter. The results had shown that the increase in the power of transformer caused a significant increase in brightness. According to the Ohm’s law and voltage division, without changing the characteristics of the light bulb, it is not possible to change the voltage, just need to change the amount of transformer with which it connects to the lamps. When the voltage is increased, the current through the bulb has to increase as well, because of Ohm's law: I=V/R and I=V/R which means that if V increases, so do I increase. The output voltage on the constant current regulator emerges between the lamps and the transformers.

Keywords: AGL, CCR, lamps, transformer, Ohm’s law

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Authors: Suresh Sahu, Abhijeet M. Vaidya, Naresh K. Maheshwari

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The efforts to understand the heat transfer behavior of supercritical water in supercritical water cooled reactor (SCWR) are ongoing worldwide to fulfill the future energy demand. The higher thermal efficiency of these reactors compared to a conventional nuclear reactor is one of the driving forces for attracting the attention of nuclear scientists. In this work, a solution procedure has been described for solving supercritical fluid flow problems in complex geometries. The solution procedure is based on non-staggered grid. All governing equations are discretized by finite volume method (FVM) in curvilinear coordinate system. Convective terms are discretized by first-order upwind scheme and central difference approximation has been used to discretize the diffusive parts. k-ε turbulence model with standard wall function has been employed. SIMPLE solution procedure has been implemented for the curvilinear coordinate system. Based on this solution method, 3-D Computational Fluid Dynamics (CFD) code has been developed. In order to demonstrate the capability of this CFD code in supercritical fluid flows, heat transfer to supercritical water in circular tubes has been considered as a test problem. Results obtained by code have been compared with experimental results reported in literature.

Keywords: curvilinear coordinate, body-fitted mesh, momentum interpolation, non-staggered grid, supercritical fluids

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Authors: Peter Adekunle, Clinton Aigbavboa, Matthew Ikuabe, Opeoluwa Akinradewo

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Contemporary building methods typically pay little attention to the built environment's greater economic, environmental, or social impacts or energy efficiency. Green construction aims to sever ties with these conventions. In order to provide better living and working conditions and lessen environmental consequences, green building today combines numerous building design, construction, and operation and maintenance approaches. As one of Sub-Saharan Africa's most industrialized nations, South Africa has a good number of green building projects. Therefore, this study examines the elements impacting the adoption of green buildings and regulations created to encourage the growth of green buildings using South Africa as a case study. The study has a survey-style design. A total of one hundred fifty (150) questionnaires were distributed to professionals in the construction industry in South Africa, of which one hundred and twenty-four (128) were returned and judged appropriate for investigation. The gathered data was examined using percentage, mean item scores, standard deviation, and Kruskal-Wallis. The findings show that cost and market circumstances are the two main elements impacting the adoption of green construction, while leadership advice is the most important policy. The study concluded that in order to encourage the construction of green buildings, additional Sub-Saharan nations should adopt these suggested policies.

Keywords: green building, Sub-Saharan Africa, building design, environmental conditions

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Authors: Balwinder Singh, Veerpaul Kaur Mann

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A composite material is formed by the combination of two or more phases or materials. Natural minerals-derived Basalt fiber is a kind of fiber being introduced in the polymer composite industry due to its good mechanical properties similar to synthetic fibers and low cost, environment friendly. Also, there is a rising trend towards the use of industrial wastes as fillers in polymer composites with the aim of improving the properties of the composites. The mechanical properties of the fiber-reinforced polymer composites are influenced by various factors like fiber length, fiber weight %, filler weight %, filler size, etc. Thus, a detailed study has been done on the characterization of short-chopped Basalt fiber-reinforced polymer matrix composites using fly ash as filler. Taguchi’s L9 orthogonal array has been used to develop the composites by considering fiber length (6, 9 and 12 mm), fiber weight % (25, 30 and 35 %) and filler weight % (0, 5 and 10%) as input parameters with their respective levels and a thorough analysis on the mechanical characteristics (tensile strength and impact strength) has been done using ANOVA analysis with the help of MINITAB14 software. The investigation revealed that fiber weight is the most significant parameter affecting tensile strength, followed by fiber length and fiber weight %, respectively, while impact characterization showed that fiber length is the most significant factor, followed by fly ash weight, respectively. Introduction of fly ash proved to be beneficial in both the characterization with enhanced values upto 5% fly ash weight. The present study on the natural fibres reinforced epoxy composites using fly ash as filler material to study the effect of input parameters on the tensile strength in order to maximize tensile strength of the composites. Fabrication of composites based on Taguchi L9 orthogonal array design of experiments by using three factors fibre type, fibre weight % and fly ash % with three levels of each factor. The Optimization of composition of natural fibre reinforces composites using ANOVA for obtaining maximum tensile strength on fabricated composites revealed that the natural fibres along with fly ash can be successfully used with epoxy resin to prepare polymer matrix composites with good mechanical properties. Paddy- Paddy fibre gives high elasticity to the fibre composite due to presence of approximately hexagonal structure of cellulose present in paddy fibre. Coir- Coir fibre gives less tensile strength than paddy fibre as Coir fibre is brittle in nature when it pulls breakage occurs showing less tensile strength. Banana- Banana fibre has the least tensile strength in comparison to the paddy & coir fibre due to less cellulose content. Higher fibre weight leads to reduction in tensile strength due to increased nuclei of air pockets. Increasing fly ash content reduces tensile strength due to nonbonding of fly ash particles with natural fibre. Fly ash is also not very strong as compared to the epoxy resin leading to reduction in tensile strength.

Keywords: tensile strength and epoxy resin. basalt Fiber, taguchi, polymer matrix, natural fiber

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Authors: Masoumeh Tabatabaee, Zahra Shahryarzadeh, Masoud R. Shishebor

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Advanced oxidation process (AOPs) is alternative method for the complete degradation many organic pollutants. When a photocatalyst absorbs radiation whose energy hν > Eg an ē from its filled valance band (VB) is promoted to its conduction band (CB) and valance band holes h+ are formed. Electron would reduce any available species, including O2, water and hydroxide ion to form hydroxyl radicals. ZnO and TiO2 are important photocatalysts with high catalytic activity that have attracted much research attention. TiO2 can only absorb a small portion of solar spectrum in the UV region and many methods such as dye sensitization, doping of other metals and using TiO2 with another semiconductor have been used to improve the photocatalytic activity of TiO2 under solar irradiation. Studies have shown that the use of metal oxides or sulfide such as WO3, MoO3, SiO2, MgO, ZnO, and CdS with TiO2 can significantly enhance the photocatalytic activity of TiO2. Due to similarity of photodegradation mechanism of ZnO with TiO2, it is a suitable semiconductor using with TiO2 and recently nanosized bicomponent TiO2-ZnO photocatalysts were prepared and used for degradation of some pollutants. In this study, Nano-sized ZnO/TiO2 composite was synthesized. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the structure and morphology of it. The effect of photocatalytic activity of prepared ZnO/TiO2 on the degradation of cyanide ion under UV was investigated. The effect of various parameters such as ZnO/TiO2 concentration, amount of photocatalyst, amount of H2O2, initial dye or cyanide ion concentration, pH and irradiation time on were investigated. Results show that more than 95% of 4 mgL-1 cyanide ion degraded after 60-min reaction time and under UV irradiation.

Keywords: photodegradation, ZnO/TiO2, nanoparticle, cyanide ion

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Authors: V. Shapaval, N. K. Afseth, D. Tzimorotas, A. Kohler

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Globally there is a dramatic increase in the demand for food, energy, materials and clean water since natural resources are limited. As a result, industries are looking for ways to reduce rest materials and to improve resource efficiency. Microorganisms have a high potential to be used as bio factories for the production of primary and secondary metabolites that represent high-value bio-products (enzymes, polyunsaturated fatty acids, bio-plastics, glucans, etc.). In order to find good microbial producers, to design suitable substrates from food rest materials and to optimize fermentation conditions, rapid analytical techniques for quantifying target bio products in microbial cells are needed. In the EU project FUST (R4SME, Fp7), we have developed a fully automated high-throughput FUST system based on micro-cultivation and FTIR spectroscopy that facilitates the screening of microorganisms, substrates and fermentation conditions for the optimization of the production of different high-value metabolites (single cell oils, bio plastics). The automated system allows the preparation of 100 samples per hour. Currently, The FUST system is in use for screening of filamentous fungi in order to find oleaginous strains with the ability to produce polyunsaturated fatty acids, and the optimization of cheap substrates, derived from food rest materials, and the optimization of fermentation conditions for the high yield of single cell oil.

Keywords: FTIR spectroscopy, FUST system, screening, biotechnology

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Authors: Shilpa Khobragade, Carlos Da Silva Granja, Niklas Sandström, Igor Efimov, Victor P. Ostanin, Wouter van der Wijngaart, David Klenerman, Sourav K. Ghosh

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Rapid, label-free and direct detection of pathogenic bacteria is critical for the prevention of disease outbreaks. This paper for the first time attempts to probe the nonlinear acoustic response of quartz crystal resonator (QCR) functionalized with specific DNA aptamers for direct detection and quantification of viable E. coli KCTC 2571 bacteria. DNA aptamers were immobilized through biotin and streptavidin conjugation, onto the gold surface of QCR to capture the target bacteria and the detection was accomplished by shift in amplitude of the peak 3f signal (3 times the drive frequency) upon binding, when driven near fundamental resonance frequency. The developed nonlinear acoustic aptasensor system demonstrated better reliability than conventional resonance frequency shift and energy dissipation monitoring that were recorded simultaneously. This sensing system could directly detect 10⁽⁵⁾ cells/mL target bacteria within 30 min or less and had high specificity towards E. coli KCTC 2571 bacteria as compared to the same concentration of S.typhi bacteria. Aptasensor response was observed for the bacterial suspensions ranging from 10⁽⁵⁾-10⁽⁸⁾ cells/mL. Conclusively, this nonlinear acoustic aptasensor is simple to use, gives real-time output, cost-effective and has the potential for rapid, specific, label-free direction detection of bacteria.

Keywords: acoustic, aptasensor, detection, nonlinear

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Authors: Sepehr Lajevardi Esfahani, Shohre Rouhani, Zahra Ranjbar

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Graphene has gained much attention owing to its unique optical and electrical properties. Charge carriers in graphene sheets (GS) carry out a linear dispersion relation near the Fermi energy and behave as massless Dirac fermions resulting in unusual attributes such as the quantum Hall effect and ambipolar electric field effect. It also exhibits nondispersive transport characteristics with an extremely high electron mobility (15000 cm²/(Vs)) at room temperature. Recently, several progresses have been achieved in the fabrication of single- or multilayer GS for functional device applications in the fields of optoelectronic such as field-effect transistors ultrasensitive sensors and organic photovoltaic cells. In addition to device applications, graphene also can serve as reinforcement to enhance mechanical, thermal, or electrical properties of composite materials. Electrophoretic deposition (EPD) is an attractive method for development of various coatings and films. It readily applied to any powdered solid that forms a stable suspension. The deposition parameters were controlled in various thicknesses. In this study, the graphene electrodeposition conditions were optimized. The results were obtained from SEM, Ohm resistance measuring technique and AFM characteristic tests. The minimum sheet resistance of electrodeposited reduced graphene oxide layers is achieved at conditions of 2 V in 10 s and it is annealed at 200 °C for 1 minute.

Keywords: electrophoretic deposition (EPD), graphene oxide (GO), electrical conductivity, electro-optical devices

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Authors: Renato André S. Silva, Nana L. F. Sampaio, Carlos J. G. Cruz, Bruno Vianna, Flávio O. Pires

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multiple stage bicycle races require high physiological loads from professional cyclists. Such demands can lead to immunosuppression and health problems. However, in this type of competition, little is known about its physiological effects on amateur athletes, who generally receive less medical support. Thus, this study analyzes the hematological effects of a multiple stage bicycle race on amateur cyclists. Seven Brazilian national amateur cyclists (34 ± 4.21 years) underwent a laboratory test to evaluate VO2Max (69.89 ± 7.43 ml⋅kg-1⋅min-1). Six days later, these volunteers raced in the Tour of Goiás, participating in five races in four days (435 km) of competition. Arterial blood samples were collected one day before and one day after the competition. The Kolmogorov-Smirnov tests were used to evaluate the data distribution and Wilcoxon to compare the two moments (p <0.05) of data collection. The results show: Red cells ↓ 7.8% (5.1 ± 0.28 vs 4.7 ± 0.37 106 / mm 3, p = 0.01); Hemoglobin ↓ 7.9% (15.1 ± 0.31 vs 13.9 ± 0.27 g / dL, p = 0.01); Leukocytes ↑ 9.5% (4946 ± 553 versus 5416 ± 1075 / mm 3, p = 0.17); Platelets ↓ 7.0% (200.2 ± 51.5 vs 186.1 ± 39.5 / mm 3, p = 0.01); LDH ↑ 11% (164.4 ± 28.5 vs 182.5 ± 20.5 U / L, p = 0.17); CK ↑ 13.5% (290.7 ± 206.1 vs 330.1 ± 90.5 U / L, p = 0.39); CK-MB ↑ 2% (15.7 ± 3.9 vs. 20.1 ± 2.9 U / L, p = 0.06); Cortizol ↓ 13.5% (12.1 ± 2.4 vs 9.9 ± 1.9 μg / dL, p = 0.01); Total testosterone ↓ 7% (453.6 ± 120.1 vs 421.7 ± 74.3 ng / dL, p = 0.12); IGF-1 ↓ 15.1% (213.8 ± 18.8 vs 181.5 ± 34.7 ng / mL, p = 0.04). This means that there was significant reductions in O2 allocation / transport capacities, vascular injury disruption, and a fortuitous reduction of muscle skeletal anabolism along with maintenance and / or slight elevation of immune function, glucose and lipid energy and myocardial damage. Therefore, the results suggest that no abnormal health effect was identified among the athletes after participating in the Tour de Goiás.

Keywords: cycling, health effects, cycling stages races, haematology

Procedia PDF Downloads 198

Authors: Ratna Dewi Kusumaningtyas, Riris Pristiyani, Heny Dewajani

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Biodiesel is commonly produced via the two main routes, i.e. the transesterification of triglycerides and the esterification of free fatty acid (FFA) using short-chain alcohols. Both the two routes have drawback in term of the side product yielded during the reaction. Transesterification reaction of triglyceride results in glycerol as side product. On the other hand, FFA esterification brings in water as side product. Both glycerol and water in the biodiesel production are managed as waste. Hence, a separation process is necessary to obtain a high purity biodiesel. Meanwhile, separation processes is generally the most capital and energy intensive part in industrial process. Therefore, to reduce the separation process, it is essential to produce biodiesel via an alternative route eliminating glycerol or water side-products. In this work, biodiesel synthesis was performed using a glycerol-free process through chemical interesterification of jatropha oil with ethyl acetate in the presence on sodium acetate catalyst. By using this method, triacetine, which is known as fuel bio-additive, is yielded instead of glycerol. This research studied the effects of catalyst concentration on the jatropha oil interesterification process in the range of 0.5 – 1.25% w/w oil. The reaction temperature and molar ratio of oil to ethyl acetate were varied at 50, 60, and 70°C, and 1:6, 1:9, 1:15, 1:30, and 1:60, respectively. The reaction time was evaluated from 0 to 8 hours. It was revealed that the best yield was obtained with the catalyst concentration of 0.5%, reaction temperature of 70 °C, molar ratio of oil to ethyl acetate at 1:60, at 6 hours reaction time.

Keywords: biodiesel, interesterification, glycerol-free, triacetine, jatropha oil

Procedia PDF Downloads 423

Authors: Michel Han, Christophe Besson, Alain Savary, Yvan Becher

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The variable flux permanent magnet synchronous motor (VF-PMSM), also called "Memory Motor", is a new generation of motor capable of modifying the magnetization state with short pulses of current during operation or standstill. The impact of such operation is the expansion of the operating range in the torque-speed characteristic and an improvement in energy efficiency at high-speed in comparison to conventional permanent magnet synchronous machines (PMSMs). This paper reviews the operating principle and the unique features of the proposed memory motor. The benefits of this concept are highlighted by comparing the performance of the rotor of the VF-PMSM to that of two PM rotors that are typically found in the industry. The investigation emphasizes the properties of the variable magnetization and presents the comparison of the torque-speed characteristic with the capability of loss reduction in a VF-PMSM by means of experimental results, especially when tests are conducted under identical conditions for each rotor (same stator, same inverter and same experimental setup). The experimental results demonstrated that the VF-PMSM gives an additional degree of freedom to optimize the efficiency over a wide speed range. Thus, with a design easy to manufacture and with the possibility of controlling the magnetization and the demagnetization of the magnets during operations, the VF-PMSM can be interesting for various applications.

Keywords: efficiency, magnetization state, memory motors, performances, permanent-magnet, synchronous machine, variable-flux, variable magnetization, wide speed application

Procedia PDF Downloads 191

Authors: Salah Guettala, nesreddine.djafarhenni, Akram Khelaifia, Rachid Chebili

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This study assesses the impact of infill walls' layout in both plan and elevation on the seismic behavior of a 3D reinforced concrete structure situated in a high seismic zone. A pushover analysis is conducted to evaluate the structure's seismic performance with various infill wall layouts, considering capacity curves, absorbed energy, inter-story drift, and performance levels. Additionally, torsional effects on the structure are examined through linear dynamic analysis. Fiber-section-based macro-modeling is utilized to simulate the behavior of infill walls. The findings indicate that the presence of infill walls enhances lateral stiffness and alters structural behavior. Moreover, the study highlights the importance of considering the effects of infill wall layout, as non-uniform layouts can degrade building performance post-earthquake, increasing inter-story drift and risk of damage or collapse. To mitigate such risks, buildings should adopt a uniform infill wall layout. Furthermore, asymmetrical placement of masonry infill walls introduces additional torsional forces, particularly when there's a lack of such walls on the first story, potentially leading to irregular stiffness and soft-story phenomena.

Keywords: RC structures, infll walls’ layout, pushover analysis, macro-model, fiber plastic hinge, torsion

Procedia PDF Downloads 59

Authors: Himanshu Kumar Gupta

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The Jaisalmer Basin is one of the parts of the Rajasthan basin in northwestern India. The presence of five major unconformities/hiatuses of varying span i.e. at the top of Archean basement, Cambrian, Jurassic, Cretaceous, and Eocene have created the foundation for constructing a sequence stratigraphic framework. Based on basin formative tectonic events and their impact on sedimentation processes three first-order sequences have been identified in Rajasthan Basin. These are Proterozoic-Early Cambrian rift sequence, Permian to Middle-Late Eocene shelf sequence and Pleistocene - Recent sequence related to Himalayan Orogeny. The Permian to Middle Eocene I order sequence is further subdivided into three-second order sequences i.e. Permian to Late Jurassic II order sequence, Early to Late Cretaceous II order sequence and Paleocene to Middle-Late Eocene II order sequence. In this study, Late Jurassic to Early Cretaceous sequence was identified and log-based interpretation of smaller order T-R cycles have been carried out. A log profile from eastern margin to western margin (up to Shahgarh depression) has been taken. The depositional environment penetrated by the wells interpreted from log signatures gave three major facies association. The blocky and coarsening upward (funnel shape), the blocky and fining upward (bell shape) and the erratic (zig-zag) facies representing distributary mouth bar, distributary channel and marine mud facies respectively. Late Jurassic Formation (Baisakhi-Bhadasar) and Early Cretaceous Formation (Pariwar) shows a lesser number of T-R cycles in shallower and higher number of T-R cycles in deeper bathymetry. Shallowest well has 3 T-R cycles in Baisakhi-Bhadasar and 2 T-R cycles in Pariwar, whereas deeper well has 4 T-R cycles in Baisakhi-Bhadasar and 8 T-R cycles in Pariwar Formation. The Maximum Flooding surfaces observed from the stratigraphy analysis indicate major shale break (high shale content). The study area is dominated by the alternation of shale and sand lithologies, which occurs in an approximate ratio of 70:30. A seismo-geological cross section has been prepared to understand the stratigraphic thickness variation and structural disposition of the strata. The formations are quite thick to the west, the thickness of which reduces as we traverse towards the east. The folded and the faulted strata indicated the compressional tectonics followed by the extensional tectonics. Our interpretation is supported with seismic up to second order sequence indicates - Late Jurassic sequence is a Highstand Systems Tract (Baisakhi - Bhadasar formations), and the Early Cretaceous sequence is Regressive to Lowstand System Tract (Pariwar Formation).

Keywords: Jaisalmer Basin, sequence stratigraphy, system tract, T-R cycle

Procedia PDF Downloads 133

Authors: Himanshu Dehra

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An experimental study was conducted for ascertaining electrical and thermal characteristics of a pair of photovoltaic (PV) modules integrated with solar wall of an outdoor room. A pre-fabricated outdoor room was setup for conducting outdoor experiments on a PV solar wall with passive and active ventilation through the outdoor room. The selective operating conditions for glass coated PV modules were utilized for establishing their electrical and thermal characteristics. The PV solar wall was made up of glass coated PV modules, a ventilated air column, and an insulating layer of polystyrene filled plywood board. The measurements collected were currents, voltages, electric power, air velocities, temperatures, solar intensities, and thermal time constant. The results have demonstrated that: i) a PV solar wall installed on a wooden frame was of more heat generating capacity in comparison to a window glass or a standalone PV module; ii) generation of electric power was affected with operation of vertical PV solar wall; iii) electrical and thermal characteristics were not significantly affected by heat and thermal storage losses; and iv) combined heat and electricity generation were function of volume of thermal and electrical resistances developed across PV solar wall. Finally, a comparison of temperature plots of passive and active ventilation envisaged that fan pressure was necessary to avoid overheating of the PV solar wall. The active ventilation was necessary to avoid over-heating of the PV solar wall and to maintain adequate ventilation of room under mild climate conditions.

Keywords: photovoltaic solar wall, solar energy, passive ventilation, active ventilation

Procedia PDF Downloads 394

Authors: J. I. Corcoles, J. D. Moya-Rico, A. Molina, J. F. Belmonte, J. A. Almendros-Ibanez

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One of the most common heat exchangers technology in engineering processes is the use of double-pipe heat exchangers (DPHx), mainly in the food industry. To improve the heat transfer performance, several passive geometrical devices can be used, such as the wall corrugation of tubes, which increases the wet perimeter maintaining a constant cross-section area, increasing consequently the convective surface area. It contributes to enhance heat transfer in forced convection, promoting secondary recirculating flows. One of the most extended tools to analyse heat exchangers' efficiency is the use of computational fluid dynamic techniques (CFD), a complementary activity to the experimental studies as well as a previous step for the design of heat exchangers. In this study, a double pipe heat exchanger behaviour with two different inner tubes, smooth and spirally corrugated tube, have been analysed. Hence, experimental analysis and steady 3-D numerical simulations using the commercial code ANSYS Workbench v. 17.0 are carried out to analyse the influence of geometrical parameters for spirally corrugated tubes at turbulent flow. To validate the numerical results, an experimental setup has been used. To heat up or cool down the cold fluid as it passes through the heat exchanger, the installation includes heating and cooling loops served by an electric boiler with a heating capacity of 72 kW and a chiller, with a cooling capacity of 48 kW. Two tests have been carried out for the smooth tube and for the corrugated one. In all the tests, the hot fluid has a constant flowrate of 50 l/min and inlet temperature of 59.5°C. For the cold fluid, the flowrate range from 25 l/min (Test 1) and 30 l/min (Test 2) with an inlet temperature of 22.1°C. The heat exchanger is made of stainless steel, with an external diameter of 35 mm and wall thickness of 1.5 mm. Both inner tubes have an external diameter of 24 mm and 1 mm thickness of stainless steel with a length of 2.8 m. The corrugated tube has a corrugation height (H) of 1.1 mm and helical pitch (P) of 25 mm. It is characterized using three non-dimensional parameters, the ratio of the corrugation shape and the diameter (H/D), the helical pitch (P/D) and the severity index (SI = H²/P x D). The results showed good agreement between the numerical and the experimental results. Hence, the lowest differences were shown for the fluid temperatures. In all the analysed tests and for both analysed tubes, the temperature obtained numerically was slightly higher than the experimental results, with values ranged between 0.1% and 0.7%. Regarding the pressure drop, the maximum differences between the values obtained numerically, and the experimental values were close to 16%. Based on the experimental and the numerical results, for the corrugated tube, it can be highlighted that the temperature difference between the inlet and the outlet of the cold fluid is 42%, higher than the smooth tube.

Keywords: corrugated tube, heat exchanger, heat transfer, numerical simulation

Procedia PDF Downloads 144

Authors: Venkata Madhusudana Rao Kapavarapu

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The Intermediate Slug Catcher (ISC) facility was built to process nominally 234 MSCFD of export gas from the booster station on a day-to-day basis and to receive liquid slugs up to 1600 m³ (10,000 BBLS) in volume when the incoming 24” gas pipelines are pigged following upsets or production of non-dew-pointed gas from gathering centers. The maximum slug sizes expected are 812 m³ (5100 BBLS) in winter and 542 m³ (3400 BBLS) in summer after operating for a month or more at 100 MMSCFD of wet gas, being 60 MMSCFD of treated gas from the booster station, combined with 40 MMSCFD of untreated gas from gathering center. The water content is approximately 60% but may be higher if the line is not pigged for an extended period, owing to the relative volatility of the condensate compared to water. In addition to its primary function as a slug catcher, the ISC facility will receive pigged liquids from the upstream and downstream segments of the 14” condensate pipeline, returned liquids from the AGRP, pigged through the 8” pipeline, and blown-down fluids from the 14” condensate pipeline prior to maintenance. These fluids will be received in the condensate flash vessel or the condensate separator, depending on the specific operation, for the separation of water and condensate and settlement of solids scraped from the pipelines. Condensate meeting the colour and 200 ppm water specifications will be dispatched to the AGRP through the 14” pipeline, while off-spec material will be returned to BS-171 via the existing 10” condensate pipeline. When they are not in operation, the existing 24” export gas pipeline and the 10” condensate pipeline will be maintained under export gas pressure, ready for operation. The gas manifold area contains the interconnecting piping and valves needed to align the slug catcher with either of the 24” export gas pipelines from the booster station and to direct the gas to the downstream segment of either of these pipelines. The manifold enables the slug catcher to be bypassed if it needs to be maintained or if through-pigging of the gas pipelines is to be performed. All gas, whether bypassing the slug catcher or returning to the gas pipelines from it, passes through black powder filters to reduce the level of particulates in the stream. These items are connected to the closed drain vessel to drain the liquid collected. Condensate from the booster station is transported to AGRP through 14” condensate pipeline. The existing 10” condensate pipeline will be used as a standby and for utility functions such as returning condensate from AGRP to the ISC or booster station or for transporting off-spec fluids from the ISC back to booster station. The manifold contains block valves that allow the two condensate export lines to be segmented at the ISC, thus facilitating bi-directional flow independently in the upstream and downstream segments, which ensures complete pipeline integrity and facility integrity. Pipeline failures will be attended to with the latest technologies by remote techno plug techniques, and repair activities will be carried out as needed. Pipeline integrity will be evaluated with ili pigging to estimate the pipeline conditions.

Keywords: integrity, oil & gas, innovation, new technology

Procedia PDF Downloads 70

Authors: D. Suman, M. Venkateshwara Rao

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Cancer is a disease caused by an uncontrolled division of abnormal cells in a part of the body, which is affecting millions of people leading to death. Even though there have been tremendous developments taken place over the last few decades the effective therapy for cancer is still not a reality. The existing techniques of cancer therapy are chemotherapy and radio therapy which are having their limitations in terms of the side effects, patient discomfort, radiation hazards and the localization of treatment. This paper describes a novel method for cancer therapy by using RF-hyperthermia application of nanoparticles. We have synthesized ferromagnetic nanoparticles and characterized by using XRD and TEM. These nanoparticles after the biocompatibility studies will be injected in to the body with a suitable tracer element having affinity to the specific tumor site. When RF energy is applied to the nanoparticles at the tumor site it produces heat of excess room temperature and nearly 41-45°C is sufficient to kill the tumor cells. We have designed a RF source generator provided with a temperature feedback controller to control the radiation induced temperature of the tumor site. The temperature control is achieved through a negative feedback mechanism of the thermocouple and a relay connected to the power source of the RF generator. This method has advantages in terms of its effect like localized therapy, less radiation, and no side effects. It has several challenges in designing the RF source provided with coils suitable for the tumour site, biocompatibility of the nanomaterials, cooling system design for the RF coil. If we can overcome these challenges this method will be a huge benefit for the society.

Keywords: hyperthermia, cancer therapy, RF source generator, nanoparticles

Procedia PDF Downloads 457

Authors: Marko Živanović, Jovana Bjekić, Maša Vukčević Marković

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Professionals and volunteers involved in refugee protection and support are on a daily basis faced with people who have experienced numerous traumatic experiences and, as such, are subjected to secondary traumatization (ST). The aim of this study was to provide insight into risk factors for ST in helpers working with refugees in Serbia. A total of 175 participants working with refugees fulfilled: Secondary Traumatization Questionnaire, checklist of refugees’ traumatic experiences, Hopkins Symptoms Checklist (HSCL) assessing depression and anxiety symptoms, quality of life questionnaire (MANSA), HEXACO personality inventory, and COPE assessing coping mechanisms. In addition, participants provided information on work-related problems. Qualitative analysis of answers to the question about most difficult part of their job has shown that burnout-related issues are clustered around three recurrent topics that can be considered as the most prominent generators of stress, namely: ‘lack of organization and cooperation’, ‘not been able to do enough’, and ‘hard to take it and to process it’. Factor analysis (Maximum likelihood extraction, Promax rotation) have shown that ST comprises of two correlated factors (r = .533, p < .01), namely Psychological deficits and Intrusions. Results have shown that risk factor for ST could be find in three interrelated sources: 1) work-related problems; 2) personality-related risk factors and 3) clients’ traumatic experiences. Among personality related factors, it was shown that risk factor for Intrusions could be find in – high Emotionality (β = .221, p < .05), and Altruism (β = .322, p < .01), while low Extraversion (β = -.365, p < .01) represents risk factor for Psychological deficits. In addition, usage of maladaptive coping mechanisms –mental disengagement (r = .253, p < .01), behavioral disengagement (r = .274, p < .01), focusing on distress and venting of emotions (r = .220, p < .05), denial (r = .164, p < .05), and substance use (r = .232, p < .01) correlate with Psychological deficits while Intrusions corelate with Mental disengagement (r = .251, p < .01) and denial (r = .183, p < .05). Regarding clients’ traumatic experiences it was shown that both quantity of traumatic events in country of origin (for Deficits r = .226, p < .01; for Intrusions r = .174, p < .05) and in transit (for Deficits r = .288, p < .01), as well as certain content-related features of such experiences (especially experiences which are severely dislocated from ‘everyday reality’) are related to ST. In addition, Psychological deficits and Intrusions have shown to be accompanied by symptoms of depression (r = .760, p < .01; r = .552, p < .01) and anxiety (r = .740, p < .01; r = .447, p < .01) and overall lower life quality (r = -.454, p < .01; r = .256, p < .01). Results indicate that psychological vulnerability of persons who are working with traumatized individuals can be found in certain personality traits, and usage of maladaptive coping mechanisms, which disable one to deal with work-related issues, and to cope with quantity and quality of traumatic experiences they were faced with, affecting ones’ psychological well-being. Acknowledgement: This research was funded by IRC Serbia.

Keywords: mental health, refugees, secondary traumatization, traumatic experiences

Procedia PDF Downloads 233

Authors: Anil Nis, Nilufer Ozyurt Zihnioglu

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The object of the study is to investigate fresh state properties of the steel fiber reinforced self-compacting concrete (SFR-SCC). Three different steel fibers; straight (Vf:0.5%), hooked-end long (Vf:0.5% and 1%) and hybrid fibers (0.5%short+0.5%long) were used in the research aiming to obtain flow properties of non-fibrous self-compacting concrete. Fly ash was used as a supplementary with an optimum dosage of 30% of the total cementitious materials. Polycarboxylic ether based high-performance concrete superplasticizer was used to get high flowability with percentages ranging from 0.81% (non-fibrous SCC) to 1.07% (hybrid SF-SCC) of the cement weight. The flowability properties of SCCs were measured via slump flow and V-funnel tests; passing ability properties of SCCs were measured with J-Ring, L-Box, and U-Box tests. Workability results indicate that small increase on the superplasticizer dosages compensate the adverse effects of steel fibers on flowability properties of SSC. However, higher dosage fiber addition has a negative effect on passing ability properties, causing blocking of the mixes. In addition, compressive strength, tensile strength, and four point bending results were given. Results indicate that SCCs including steel fibers have superior performances on tensile and bending strength of concrete. Crack bridging capability of steel fibers prevents concrete from splitting, yields higher deformation and energy absorption capacities than non-fibrous SCCs.

Keywords: fiber reinforced self-compacting concrete, fly ash, fresh state properties, steel fiber

Procedia PDF Downloads 222