Search results for: phenomenal material world
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13855

Search results for: phenomenal material world

11575 Evaluation of Environmental Impact Assessment of Dam Using GIS/Remote Sensing-Review

Authors: Ntungamili Kenosi, Moatlhodi W. Letshwenyo

Abstract:

Negative environmental impacts due to construction of large projects such as dams have become an important aspect of land degradation. This paper will review the previous literature on the previous researches or study in the same area of study in the other parts of the world. After dam has been constructed, the actual environmental impacts are investigated and compared to the predicted results of the carried out Environmental Impact Assessment. GIS and Remote Sensing, play an important role in generating automated spatial data sets and in establishing spatial relationships. Results from other sources shows that the normalized vegetation index (NDVI) analysis was used to detect the spatial and temporal change of vegetation biomass in the study area. The result indicated that the natural vegetation biomass is declining. This is mainly due to the expansion of agricultural land and escalating human made structures in the area. Urgent environmental conservation is necessary when adjoining projects site. Less study on the evaluation of EIA on dam has been conducted in Botswana hence there is a need for the same study to be conducted and then it will be easy to be compared to other studies around the world.

Keywords: Botswana, dam, environmental impact assessment, GIS, normalized vegetation index (NDVI), remote sensing

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11574 Multifunctional Polydopamine-Silver-Polydopamine Nanofilm With Applications in Digital Microfluidics and SERS

Authors: Yilei Xue, Yat-Hing Ham, Wenting Qiu, Wan Chan, Stefan Nagl

Abstract:

Polydopamine (PDA) is a popular material in biological and medical applications due to its excellent biocompatibility, outstanding physicochemical properties, and facile fabrication. In this project, a new sandwich-structured PDA and silver (Ag) hybrid material named PDA-Ag-PDA was synthesized and characterized layer-by-layer, where silver nanoparticles (Ag NPs) are wrapped in PDA coatings, using SEM, AFM, 3D surface metrology, and contact angle meter. The silver loading capacity is positively proportional to the roughness value of the initial PDA film. This designed film was subsequently integrated within a digital microfluidic (DMF) platform coupling with an oxygen sensor layer for on-chip antibacterial assay. The concentration of E. coli was quantified on DMF by real-time monitoring oxygen consumption during E. coli growth with the optical oxygen sensor layer. The PDA-Ag-PDA coating shows an 99.9% reduction in E. coli population under non-nutritive condition with 1-hour treatment and has a strong growth inhibition of E. coliin nutrient LB broth as well. Furthermore, PDA-Ag-PDA film maintaining a low cytotoxicity effect to human cells. After treating with PDA-Ag-PDA film for 24 hours, 82% HEK 293 and 86% HeLa cells were viable. The SERS enhancement factor of PDA-Ag-PDA is estimated to be 1.9 × 104 using Rhodamine 6G (R6G). Multifunctional PDA-Ag-PDA coating provides an alternative platform to conjugate biomolecules and perform biological applications on DMF, in particular, for the adhesive protein and cell study.

Keywords: polydopamine, silver nanoparticles, digital microfluidic, optical sensor, antimicrobial assay, SERS

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11573 Effect of Climate Change on Rainfall Induced Failures for Embankment Slopes in Timor-Leste

Authors: Kuo Chieh Chao, Thishani Amarathunga, Sangam Shrestha

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Rainfall induced slope failures are one of the most damaging and disastrous natural hazards which occur frequently in the world. This type of sliding mainly occurs in the zone above the groundwater level in silty/sandy soils. When the rainwater begins to infiltrate into the vadose zone of the soil, the negative pore-water pressure tends to decrease and reduce the shear strength of soil material. Climate change has resulted in excessive and unpredictable rainfall in all around the world, resulting in landslides with dire consequences to human lives and infrastructure. Such problems could be overcome by examining in detail the causes for such slope failures and recommending effective repair plans for vulnerable locations by considering future climatic change. The selected area for this study is located in the road rehabilitation section from Maubara to Mota Ain road in Timor-Leste. Slope failures and cracks have occurred in 2013 and after repairs reoccurred again in 2017 subsequent to heavy rains. Both observed and future predicted climate data analyses were conducted to understand the severe precipitation conditions in past and future. Observed climate data were collected from NOAA global climate data portal. CORDEX data portal was used to collect Regional Climate Model (RCM) future predicted climate data. Both observed and RCM data were extracted to location-based data using ArcGIS Software. Linear scaling method was used for the bias correction of future data and bias corrected climate data were assigned to GeoStudio Software. Precipitations of wet seasons (December to March ) in 2007 to 2013 is higher than 2001-2006 period and it is more than nearly 40% higher precipitation than usual monthly average precipitation of 160mm.The results of seepage analyses which were carried out using SEEP/W model with observed climate, clearly demonstrated that the pore water pressure within the fill slope was significantly increased due to the increase of the infiltration during the wet season of 2013.One main Regional Climate Models (RCM) was analyzed in order to predict future climate variation under two Representative Concentration Pathways (RCPs).In the projected period of 76 years ahead from 2014, shows that the amount of precipitation is considerably getting higher in the future in both RCP 4.5 and RCP 8.5 emission scenarios. Critical pore water pressure conditions during 2014-2090 were used in order to recommend appropriate remediation methods. Results of slope stability analyses indicated that the factor of safety of the fill slopes was reduced from 1.226 to 0.793 during the dry season to wet season in 2013.Results of future slope stability which were obtained using SLOPE/W model for the RCP emissions scenarios depict that, the use of tieback anchors and geogrids in slope protection could be effective in increasing the stability of slopes to an acceptable level during the wet seasons. Moreover, methods and procedures like monitoring of slopes showing signs or susceptible for movement and installing surface protections could be used to increase the stability of slopes.

Keywords: climate change, precipitation, SEEP/W, SLOPE/W, unsaturated soil

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11572 Carbon Fiber Manufacturing Conditions to Improve Interfacial Adhesion

Authors: Filip Stojcevski, Tim Hilditch, Luke Henderson

Abstract:

Although carbon fibre composites are becoming ever more prominent in the engineering industry, interfacial failure still remains one of the most common limitations to material performance. Carbon fiber surface treatments have played a major role in advancing composite properties however research into the influence of manufacturing variables on a fiber manufacturing line is lacking. This project investigates the impact of altering carbon fiber manufacturing conditions on a production line (specifically electrochemical oxidization and sizing variables) to assess fiber-matrix adhesion. Pristine virgin fibers were manufactured and interfacial adhesion systematically assessed from a microscale (single fiber) to a mesoscale (12k tow), and ultimately a macroscale (laminate). Correlations between interfacial shear strength (IFSS) at each level is explored as a function of known interfacial bonding mechanisms; namely mechanical interlocking, chemical adhesion and fiber wetting. Impact of these bonding mechanisms is assessed through extensive mechanical, topological and chemical characterisation. They are correlated to performance as a function of IFSS. Ultimately this study provides a bottoms up approach to improving composite laminates. By understanding the scaling effects from a singular fiber to a composite laminate and linking this knowledge to specific bonding mechanisms, material scientists can make an informed decision on the manufacturing conditions most beneficial for interfacial adhesion.

Keywords: carbon fibers, interfacial adhesion, surface treatment, sizing

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11571 Caring and Sustainable Government: An Examination of Political Vision of Jeong Do-Jeon

Authors: Hyeon Sop Baek

Abstract:

This paper will briefly investigate Jeong Do-jeon’s political philosophy. Jeong Do-jeon was a Korean Confucian philosopher and politician during the turbulent 14th Century who revolted against the old order, founded Joseon Dynasty, and significantly impacted the development of Korean culture. Jeong’s vision of an ideal state involved a polity that has its roots in the people -that is, an ideal government prioritizes caring for the welfare of the people, respecting and attending to the diverse opinions and concerns of the people, and relies on the genuine, voluntary support of the people. With the neo-Confucian worldview in mind -that every human being has the equal potential to become a moral person- Jeong sought to create a world suitable for everybody to contribute to the decision-making procedure and be able to realize their potential fully. This paper will first examine his works and present a quick overview of his vision of the ideal government. Then, it will examine the Confucian virtues of ren (仁) and yi (義) and how they formulate the basis of his philosophy, and then discuss the central features of his vision of government: popular mandate, equity of wealth, promoting freedom of expression and political participation, and elevating caring disposition as the paramount quality of the political leaders. Furthermore, this paper aims to analyze the element of care inherent within his political philosophy, namely his view on the dynamics of power, nurturing the people, and noncoercive justice. Finally, a discussion on why his philosophy is still relevant in the contemporary context will be provided. Jeong’s view aimed at building a sustainable model of government, by proposing that the people should be the foundation of a state and that they need to be carefully nurtured so they can realize their inborn potential and continue to contribute to the sustenance of the world, is the focal point of Jeong’s philosophy. Just as he sought to rebuild his world following the turmoils of the 14th Century, his philosophy still has a substantial implication on how we should strive to rebuild our society today.

Keywords: Korea, Confucianism, Jeong Do-jeon, Joseon, Korean philosophy, political philosophy

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11570 Research Study on the Concept of Unity of Ummah and Its Sources in the Light of Islamic Teachings

Authors: Ghazi Abdul Rehman Qasmi

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Islam is the preacher and torch-bearer of unity and solidarity. All the followers of Islam are advised to be united. Islam strongly condemns those elements which disunite the unity of Muslim Ummah. Like pearls in a rosary, Islam has united the Muslims from all over the world in the wreath of unity and forbade the Muslims to avoid separation and to be disintegrated. The aspect of unity is prominent in all divine injunctions and about worship. By offering five times obligatory congregational prayers, passion of mutual love and affection is increased and on the auspicious days like Friday, Eid-ul-fiter and Eid-ul-azha, majority of the Muslims come together at central places to offer these congregational prayers. Thus unity and harmony among the Muslims can be seen. Similarly the Muslim pilgrims from all over the world eliminate all kind of worldly discrimination to perform many rituals of pilgrimage while wearing white color cloth as a dress. Pilgrimage is a demonstration of Islamic strength. When the Muslims from all over the world perform the same activities together and they offer their prayers under the leadership of one leader (IMAM). Muslims come together on the occasion of pilgrimage to perform Tawaf (seven circuits,first three circuits at a hurried pace(Rammal) and followed by four times, more closely, at a leisurely pace, round the Holy Kaabah to perform circumambulation known as Tawaf in religious terminology,Saee(running or walking briskly seven times between two small hills Safa&Marwa), Ramy-al-jamarat (throwing pebbles at the stone pillars, symbolizing the devil). In this way dignity and sublimity of Islam is increased and unity and integrity of Muslim Ummah is promoted also. By studying the life history of Hazrat Muhammad (P.B.U.H) we come to know that our Holy Prophet (P.B.U.H) has put emphasis on unity and integrity. We have to follow the Islamic teachings to create awareness among the members of Muslim Ummah. In the light of the Holy Quran and Sunnah, we have to utilize all the sources and potential for this noble cause.

Keywords: unity, Ummah, sources, Islamic teaching

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11569 Use of Geometrical Relationship in the Ancient Vihara Housing Reclining Buddha Remains of Thailand's Kamphaeng Phet World Heritage Site

Authors: Vacharee Svamivastu

Abstract:

This research investigates the application of geometrical relationship to the ancient religious assembly hall (Vihara) housing a reclining Buddha statue of Thailand's Kamphaeng Phet Historical Park. The study utilizes the archaeological and wooden roof structure remains of the Vihara as the prima facie evidence, supplemented with evidence from other active archaeological sites with architectural kinship as well as Buddhist ideology. At present, the wooden roofs of the Vihara fell prey to the elements and there remain only the base, columns and enclosing walls. Unlike typical Viharas whose floor plan are of rectangular shape, the floor plan of the Vihara housing the reclining Buddha is of square configuration of 25x25m. Further observation has revealed the utilization of large laterite boulders as the principal construction material of the assembly hall (Vihara) columns. The laterite columns are of square shape (1x1m) and various heights (H), ranging from 3.50m to 5.50m. The erection of the Vihara required a total of 36 laterite columns. The pattern of columns arrangement is of two rows of inner columns, two rows of outer columns and two rows of verandah columns. The space between pairs of the verandah columns was stacked with laterite blocks of varying sizes to form the Vihara walls with small openings for ventilation. Upon applying the geometrical relationship-grid system to the Vihara, the results reveal that the placement of the columns was deliberately and masterfully undertaken such that the center of the square-shaped Vihara is conspicuously spacious so as to accommodate the sacred reclining Buddha statue. The elegance of the Vihara demonstrates the ingenious application of geometrical relationship to transforming a space into a structure (i.e. Vihara) of architectural and religious significance.

Keywords: geometrical relationship, the religious assembly hall, Vihara, Kamphaeng Phet School of Master Builder

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11568 Minimizing Students' Learning Difficulties in Mathematics

Authors: Hari Sharan Pandit

Abstract:

Mathematics teaching in Nepal has been centralized and guided by the notion of transfer of knowledge and skills from teachers to students. The overemphasis on the ‘algorithm-centric’ approach to mathematics teaching and the focus on ‘role–learning’ as the ultimate way of solving mathematical problems since the early years of schooling have been creating severe problems in school-level mathematics in Nepal. In this context, the author argues that students should learn real-world mathematical problems through various interesting, creative and collaborative, as well as artistic and alternative ways of knowing. The collaboration-incorporated pedagogy is a distinct pedagogical approach that offers a better alternative as an integrated and interdisciplinary approach to learning that encourages students to think more broadly and critically about real-world problems. The paper, as a summarized report of action research designed, developed and implemented by the author, focuses on the needs and usefulness of collaboration-incorporated pedagogy in the Nepali context to make mathematics teaching more meaningful for producing creative and critical citizens. This paper is useful for mathematics teachers, teacher educators and researchers who argue on arts integration in mathematics teaching.

Keywords: peer teaching, metacognitive approach, mitigating, action research

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11567 Questions of Subjectivity in Establishing Plurality in Indian Women’s Autobiographies

Authors: Angkayarkan Vinayakaselvi

Abstract:

This paper aims at unpacking the questions of subjectivity and their role in altering and redefining the constructed images of self and community as represented in chosen Indian women’s autobiographies. India is a country of plurality and this plurality is further extended by diasporic explorations. As the third world feminism questioned the Euro-American views on homogenizing the socio-cultural condition of women of all over the world, Indian feminism needs to critique the view that all Indian women are one and the same. Similar to the plural nature of nation, the nature and condition of women, too, are plural in India. Indian women are differentiated by caste, class, and region. A critical scrutiny of autobiographies written by Indian women belong to different socio-cultural groups – Northeast Indian, Dalit and Diasporic categories – will assess the impact of education, profession and socio-cultural and economic status on Indian Women. Such a critique would highlight the heterogeneous subjectivity of Indian women. The images/selves of women as represented through these autobiographies are chosen with an aim to unmask and challenge, through ordering and positioning, the capitalist politics of literary representations of Indian women’s formation of 'her-self'. Methodologies and subjects associated with literature are considered essential for understanding and combating women’s oppression and empowerment. The representation of self in personal autobiographical history could be treated as the history of entire nation as personal is always political in feminist writings. The chosen narrators who are well-educated, well-settled, professional women of letters are capable of assessing, critiquing and re/articulating the shifting paradigms of women’s lives. Despite these factors, the textual spaces possess evidences to establish the facts that these women undergo sufferings, and they counter design cultural specific strategies for their empowerment. These metafictional self-conscious synecdoches extend to include the world of entire women. Thus these autobiographical texts could be reinterpreted as a searing critique of Indian society based on woman’s personal life.

Keywords: ethnicity and diversity, gender studies, Indian women’s autobiographies, subjectivity

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11566 Integrated Manufacture of Polymer and Conductive Tracks for Functional Objects Fabrication

Authors: Barbara Urasinska-Wojcik, Neil Chilton, Peter Todd, Christopher Elsworthy, Gregory J. Gibbons

Abstract:

The recent increase in the application of Additive Manufacturing (AM) of products has resulted in new demands on capability. The ability to integrate both form and function within printed objects is the next frontier in the 3D printing area. To move beyond prototyping into low volume production, we demonstrate a UK-designed and built AM hybrid system that combines polymer based structural deposition with digital deposition of electrically conductive elements. This hybrid manufacturing system is based on a multi-planar build approach to improve on many of the limitations associated with AM, such as poor surface finish, low geometric tolerance, and poor robustness. Specifically, the approach involves a multi-planar Material Extrusion (ME) process in which separated build stations with up to 5 axes of motion replace traditional horizontally-sliced layer modeling. The construction of multi-material architectures also involved using multiple print systems in order to combine both ME and digital deposition of conductive material. To demonstrate multi-material 3D printing, three thermoplastics, acrylonitrile butadiene styrene (ABS), polyamide 6,6/6 copolymers (CoPA) and polyamide 12 (PA) were used to print specimens, on top of which our high viscosity Ag-particulate ink was printed in a non-contact process, during which drop characteristics such as shape, velocity, and volume were assessed using a drop watching system. Spectroscopic analysis of these 3D printed materials in the IR region helped to determine the optimum in-situ curing system for implementation into the AM system to achieve improved adhesion and surface refinement. Thermal Analyses were performed to determine the printed materials glass transition temperature (Tg), stability and degradation behavior to find the optimum annealing conditions post printing. Electrical analysis of printed conductive tracks on polymer surfaces during mechanical testing (static tensile and 3-point bending and dynamic fatigue) was performed to assess the robustness of the electrical circuits. The tracks on CoPA, ABS, and PA exhibited low electrical resistance, and in case of PA resistance values of tracks remained unchanged across hundreds of repeated tensile cycles up to 0.5% strain amplitude. Our developed AM printer has the ability to fabricate fully functional objects in one build, including complex electronics. It enables product designers and manufacturers to produce functional saleable electronic products from a small format modular platform. It will make 3D printing better, faster and stronger.

Keywords: additive manufacturing, conductive tracks, hybrid 3D printer, integrated manufacture

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11565 Characterizing Solid Glass in Bending, Torsion and Tension: High-Temperature Dynamic Mechanical Analysis up to 950 °C

Authors: Matthias Walluch, José Alberto Rodríguez, Christopher Giehl, Gunther Arnold, Daniela Ehgartner

Abstract:

Dynamic mechanical analysis (DMA) is a powerful method to characterize viscoelastic properties and phase transitions for a wide range of materials. It is often used to characterize polymers and their temperature-dependent behavior, including thermal transitions like the glass transition temperature Tg, via determination of storage and loss moduli in tension (Young’s modulus, E) and shear or torsion (shear modulus, G) or other testing modes. While production and application temperatures for polymers are often limited to several hundred degrees, material properties of glasses usually require characterization at temperatures exceeding 600 °C. This contribution highlights a high temperature setup for rotational and oscillatory rheometry as well as for DMA in different modes. The implemented standard convection oven enables the characterization of glass in different loading modes at temperatures up to 950 °C. Three-point bending, tension and torsional measurements on different glasses, with E and G moduli as a function of frequency and temperature, are presented. Additional tests include superimposing several frequencies in a single temperature sweep (“multiwave”). This type of test results in a considerable reduction of the experiment time and allows to evaluate structural changes of the material and their frequency dependence. Furthermore, DMA in torsion and tension was performed to determine the complex Poisson’s ratio as a function of frequency and temperature within a single test definition. Tests were performed in a frequency range from 0.1 to 10 Hz and temperatures up to the glass transition. While variations in the frequency did not reveal significant changes of the complex Poisson’s ratio of the glass, a monotonic increase of this parameter was observed when increasing the temperature. This contribution outlines the possibilities of DMA in bending, tension and torsion for an extended temperature range. It allows the precise mechanical characterization of material behavior from room temperature up to the glass transition and the softening temperature interval. Compared to other thermo-analytical methods, like Dynamic Scanning Calorimetry (DSC) where mechanical stress is neglected, the frequency-dependence links measurement results (e.g. relaxation times) to real applications

Keywords: dynamic mechanical analysis, oscillatory rheometry, Poisson's ratio, solid glass, viscoelasticity

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11564 Virtual Prototyping of LED Chip Scale Packaging Using Computational Fluid Dynamic and Finite Element Method

Authors: R. C. Law, Shirley Kang, T. Y. Hin, M. Z. Abdullah

Abstract:

LED technology has been evolving aggressively in recent years from incandescent bulb during older days to as small as chip scale package. It will continue to stay bright in future. As such, there is tremendous pressure to stay competitive in the market by optimizing products to next level of performance and reliability with the shortest time to market. This changes the conventional way of product design and development to virtual prototyping by means of Computer Aided Engineering (CAE). It comprises of the deployment of Finite Element Method (FEM) and Computational Fluid Dynamic (CFD). FEM accelerates the investigation for early detection of failures such as crack, improve the thermal performance of system and enhance solder joint reliability. CFD helps to simulate the flow pattern of molding material as a function of different temperature, molding parameters settings to evaluate failures like voids and displacement. This paper will briefly discuss the procedures and applications of FEM in thermal stress, solder joint reliability and CFD of compression molding in LED CSP. Integration of virtual prototyping in product development had greatly reduced the time to market. Many successful achievements with minimized number of evaluation iterations required in the scope of material, process setting, and package architecture variant have been materialized with this approach.

Keywords: LED, chip scale packaging (CSP), computational fluid dynamic (CFD), virtual prototyping

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11563 Reinventing Education Systems: Towards an Approach Based on Universal Values and Digital Technologies

Authors: Ilyes Athimni, Mouna Bouzazi, Mongi Boulehmi, Ahmed Ferchichi

Abstract:

The principles of good governance, universal values, and digitization are among the tools to fight corruption and improve the quality of service delivery. In recent years, these tools have become one of the most controversial topics in the field of education and a concern of many international organizations and institutions against the problem of corruption. Corruption in the education sector, particularly in higher education, has negative impacts on the quality of education systems and on the quality of administrative or educational services. Currently, the health crisis due to the spread of the COVID-19 pandemic reveals the difficulties encountered by education systems in most countries of the world. Due to the poor governance of these systems, many educational institutions were unable to continue working remotely. To respond to these problems encountered by most education systems in many countries of the world, our initiative is to propose a methodology to reinvent education systems based on global values and digital technologies. This methodology includes a work strategy for educational institutions, whether in the provision of administrative services or in the teaching method, based on information and communication technologies (ICTs), intelligence artificial, and intelligent agents. In addition, we will propose a supervisory law that will be implemented and monitored by intelligent agents to improve accountability, transparency, and accountability in educational institutions. On the other hand, we will implement and evaluate a field experience by applying the proposed methodology in the operation of an educational institution and comparing it to the traditional methodology through the results of teaching an educational program. With these specifications, we can reinvent quality education systems. We also expect the results of our proposal to play an important role at local, regional, and international levels in motivating governments of countries around the world to change their university governance policies.

Keywords: artificial intelligence, corruption in education, distance learning, education systems, ICTs, intelligent agents, good governance

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11562 Magnetic Braking System of an Elevator in the Event of Sudden Breakage of the Hoisting Cable

Authors: Amita Singha

Abstract:

The project describes the scope of magnetic braking. The potential applications of the braking system can be a de-accelerating system to increase the safety of an elevator or any guided rail transportation system.

Keywords: boost and buck converter, electromagnet, elevator, ferromagnetic material, sensor, solenoid, timer

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11561 Historiography of Wood Construction in Portugal

Authors: João Gago dos Santos, Paulo Pereira Almeida

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The present study intends to deepen and understand the reasons that led to the decline and disappearance of wooden construction systems in Portugal, for that reason, its use in history must be analyzed. It is observed that this material was an integral part of the construction systems in Europe and Portugal for centuries, and it is possible to conclude that its decline happens with the appearance of hybrid construction and later with the emergence and development of reinforced concrete technology. It is also verified that wood as a constructive element, and for that reason, an element of development had great importance in national construction, with its peak being the Pombaline period, after the 1755 earthquake. In this period, the great scarcity of materials in the metropolis led to the import wood from Brazil for the reconstruction of Lisbon. This period is linked to an accentuated exploitation of forests, resulting in laws and royal decrees aimed at protecting them, guaranteeing the continued existence of profitable forests, crucial to the reconstruction effort. The following period, with the gradual loss of memory of the catastrophe, resulted in a construction that was weakened structurally as a response to a time of real estate speculation and great urban expansion. This was the moment that precluded the inexistence of the use of wood in construction. At the beginning of the 20th century and in the 30s and 40s, with the appearance and development of reinforced concrete, it became part of the great structures of the state, and it is considered a versatile material capable of resolving issues throughout the national territory. It is at this point that the wood falls into disuse and practically disappears from the new works produced.

Keywords: construction history, construction in portugal, construction systems, wood construction

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11560 Slave Museums and a Site of Democratic Pedagogy: Engagement, Healing and Tolerance

Authors: Elaine Stavro

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In our present world where acts of incivility, intolerance and anger towards minority communities is on the rise, the ways museum practices cultivate ethical generosity is of interest. Democratic theorists differ as to how they believe respect can be generated through active participation. Allowing minority communities a role in determining what artifacts will be displayed and how they will be displayed has been an important step in generating respect. In addition, the rise of indigenous museums, slave museums and curators who represent these communities, contribute to the communication of their history of oppression. These institutional practices have been supplemented by the handling of objects, recognition stories and multisensory exhibitions. Psychoanalysis, object relations theorists believe that the handling of objects: amenable objects and responsive listeners will trigger the expression of anomie, alienation and traumatizing experiences. Not only memorializing but engaging with one’s lose in a very personal way can facilitate the process of mourning. Manchester Museum (UK) gathered together Somalian refugees, who in the process of handling their own objects and those offered at the museum, began to tell their stories. Democratic theorists (especially affect theorists or vital materialists or Actor Network theorists) believe that things can be social actants- material objects have agentic capacities that humans should align with. In doing so, they challenge social constructivism that attributes power to interpreted things, but like them they assume an openness or responsiveness to Otherness can be cultivated. Rich sensory experiences, corporeal engagement (devices that involve bodily movement or objects that involve handling) auditory experiences (songs) all contribute to improve one’s responsiveness and openness to Others. This paper will focus specifically on slave museums/ and exhibits in the U.K, the USA., South Africa to explore and evaluate their democratic strategies in cultivating tolerant practices via the various democratic avenues outlined above.

Keywords: democratic pedagogy, slave exhibitions, affect/emotion, object handling

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11559 Texturing of Tool Insert Using Femtosecond Laser

Authors: Ashfaq Khan, Aftab Khan, Mushtaq Khan, Sarem Sattar, Mohammad A Sheikh, Lin Li

Abstract:

Chip removal processes are one of key processes of the manufacturing industry where chip removal is conducted by tool inserts of exceptionally hard materials. Tungsten carbide has been extensively used as tool insert for machining processes involving chip removal processes. These hard materials are generally fabricated by single step sintering process as further modification after fabrication in these materials cannot be done easily. Advances in tool surface modification have revealed that advantages such as improved tribological properties and extended tool life can be harnessed from the same tool by texturing the tool rake surface. Moreover, it has been observed that the shape and location of the texture also influences the behavior. Although texturing offers plentiful advantages the challenge lies in the generation of textures on the tool surface. Extremely hard material such as diamond is required to process tungsten carbide. Laser is unique processing tool that does not have a physical contact with the material and thus does not wear. In this research the potential of utilizing laser for texturing of tungsten carbide to develop custom features would be studied. A parametric study of texturing of Tungsten Carbide with a femtosecond laser would be conducted to investigate the process parameters and establish the feasible processing window. The effect of fluence, scan speed and number of repetition would be viewed in detail. Moreover, the mechanism for the generation of features would also be reviewed.

Keywords: laser, texturing, femtosecond, tungsten carbide

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11558 Approaching the Spatial Multi-Objective Land Use Planning Problems at Mountain Areas by a Hybrid Meta-Heuristic Optimization Technique

Authors: Konstantinos Tolidis

Abstract:

The mountains are amongst the most fragile environments in the world. The world’s mountain areas cover 24% of the Earth’s land surface and are home to 12% of the global population. A further 14% of the global population is estimated to live in the vicinity of their surrounding areas. As urbanization continues to increase in the world, the mountains are also key centers for recreation and tourism; their attraction is often heightened by their remarkably high levels of biodiversity. Due to the fact that the features in mountain areas vary spatially (development degree, human geography, socio-economic reality, relations of dependency and interaction with other areas-regions), the spatial planning on these areas consists of a crucial process for preserving the natural, cultural and human environment and consists of one of the major processes of an integrated spatial policy. This research has been focused on the spatial decision problem of land use allocation optimization which is an ordinary planning problem on the mountain areas. It is a matter of fact that such decisions must be made not only on what to do, how much to do, but also on where to do, adding a whole extra class of decision variables to the problem when combined with the consideration of spatial optimization. The utility of optimization as a normative tool for spatial problem is widely recognized. However, it is very difficult for planners to quantify the weights of the objectives especially when these are related to mountain areas. Furthermore, the land use allocation optimization problems at mountain areas must be addressed not only by taking into account the general development objectives but also the spatial objectives (e.g. compactness, compatibility and accessibility, etc). Therefore, the main research’s objective was to approach the land use allocation problem by utilizing a hybrid meta-heuristic optimization technique tailored to the mountain areas’ spatial characteristics. The results indicates that the proposed methodological approach is very promising and useful for both generating land use alternatives for further consideration in land use allocation decision-making and supporting spatial management plans at mountain areas.

Keywords: multiobjective land use allocation, mountain areas, spatial planning, spatial decision making, meta-heuristic methods

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11557 Food Processing Technology and Packaging: A Case Study of Indian Cashew-Nut Industry

Authors: Parashram Jakappa Patil

Abstract:

India is the global leader in world cashew business and cashew-nut industry is one of the important food processing industries in world. However India is the largest producer, processor, exporter and importer eschew in the world. India is providing cashew to the rest of the world. India is meeting world demand of cashew. India has a tremendous potential of cashew production and export to other countries. Every year India earns more than 2000 cores rupees through cashew trade. Cashew industry is one of the important small scale industries in the country which is playing significant role in rural development. It is generating more than 400000 jobs at remote area and 95% cashew worker are women, it is giving income to poor cashew farmers, majority cashew processing units are small and cottage, it is helping to stop migration from young farmers for employment opportunities, it is motivation rural entrepreneurship development and it is also helping to environment protection etc. Hence India cashew business is very important agribusiness in India which has potential make inclusive development. World Bank and IMF recognized cashew-nut industry is one the important tool for poverty eradication at global level. It shows important of cashew business and its strong existence in India. In spite of such huge potential cashew processing industry is facing different problems such as lack of infrastructure ability, lack of supply of raw cashew, lack of availability of finance, collection of raw cashew, unavailability of warehouse, marketing of cashew kernels, lack of technical knowledge and especially processing technology and packaging of finished products. This industry has great prospects such as scope for more cashew cultivation and cashew production, employment generation, formation of cashew processing units, alcohols production from cashew apple, shield oil production, rural development, poverty elimination, development of social and economic backward class and environment protection etc. This industry has domestic as well as foreign market; India has tremendous potential in this regard. The cashew is a poor men’s crop but rich men’s food. The cashew is a source of income and livelihood for poor farmers. Cashew-nut industry may play very important role in the development of hilly region. The objectives of this paper are to identify problems of cashew processing and use of processing technology, problems of cashew kernel packaging, evolving of cashew processing technology over the year and its impact on final product and impact of good processing by adopting appropriate technology packaging on international trade of cashew-nut. The most important problem of cashew processing industry is that is processing and packaging. Bad processing reduce the quality of cashew kernel at large extent especially broken of cashew kernel which has very less price in market compare to whole cashew kernel and not eligible for export. On the other hand if there is no good packaging of cashew kernel will get moisture which destroy test of it. International trade of cashew-nut is depend of two things one is cashew processing and other is packaging. This study has strong relevance because cashew-nut industry is the labour oriented, where processing technology is not playing important role because 95% processing work is manual. Hence processing work was depending on physical performance of worker which makes presence of large workforce inevitable. There are many cashew processing units closed because they are not getting sufficient work force. However due to advancement in technology slowly this picture is changing and processing work get improve. Therefore it is interesting to explore all the aspects in context of cashew processing and packaging of cashew business.

Keywords: cashew, processing technology, packaging, international trade, change

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11556 Carbon Nanomaterials from Agricultural Wastes for Adsorption of Organic Pollutions

Authors: Magdalena Blachnio, Viktor Bogatyrov, Mariia Galaburda, Anna Derylo-Marczewska

Abstract:

Agricultural waste materials from traditional oil mill and after extraction of natural raw materials in supercritical conditions were used for the preparation of carbon nanomaterials (activated carbons) by two various methods. Chemical activation using acetic acid and physical activation with a gaseous agent (carbon dioxide) were chosen as mild and environmentally friendly ones. The effect of influential factors: type of raw material, temperature and activation agent on the porous structure characteristics of the materials was discussed by using N₂ adsorption/desorption isotherms at 77 K. Furthermore scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were employed to examine the physicochemical properties of the obtained sorbents. Selection of a raw material and an optimization of the conditions of the synthesis process, allowed to obtain the cheap sorbents with a targeted distribution of pores enabling effective adsorption of the model organic pollutants carried out in the multicomponent systems. Adsorption behavior (capacity and rate) of the chosen activated carbons was estimated by utilizing Crystal violet (CV), 4-chlorophenoxyacetic acid (4-CPA), 2.4-dichlorophenoxyacetic acid (2.4-D) as the adsorbates. Both rate and adsorption capacity of the organics on the sorbents evidenced that the activated carbons could be effectively used in sewage treatment plants. The mechanisms of organics adsorption were studied and correlated with activated carbons properties.

Keywords: activated carbon, adsorption equilibrium, adsorption kinetics, organics adsorption

Procedia PDF Downloads 168
11555 Determination of Failure Modes of Screwed Connections in Cold-Formed Steel Structures

Authors: Mahyar Maali, Merve Sagiroglu

Abstract:

Steel, which is one of the base materials we prefer in the building construction, is the material with the highest ratio to weight of carrying capacity. Due to the carrying capacity, lighter and better quality steel in smaller sections and sizes has recently been used as a frame system in cold-formed steel structures. While light steel elements used as secondary frame elements during the past, they have nowadays started to be preferred as the main frame in low/middle story buildings and detached houses with advantages such as quick and easy installation, time-saving, and small amount of scrap. It is also economically ideal because the weight of structure is lighter than other steel profiles. Structural performances and failure modes of cold-formed structures are different from conventional ones due to their thin-walled structures. One of the most important elements of light steel structures to ensure stability is the connection. The screwed connections, which have self-drilling properties with special drilling tools, are widely used in the installation of cold-formed profiles. The length of the screw is selected according to the total thickness of the elements after the screw thickness is determined according to the elements of connections. The thickness of the material depends on the length of the drilling portion at the end of the screw. The shear tests of plates connected with self-drilling screws are carried out depending on the screw length, and their failure modes were evaluated in this study.

Keywords: cold-formed steel, screwed connection, connection, screw length

Procedia PDF Downloads 173
11554 Direct Measurements of the Electrocaloric Effect in Solid Ferroelectric Materials via Thermoreflectance

Authors: Layla Farhat, Mathieu Bardoux, Stéphane Longuemart, Ziad Herro, Abdelhak Hadj Sahraoui

Abstract:

Electrocaloric (EC) effect refers to the isothermal entropy or adiabatic temperature changes of a dielectric material induced by an external electric field. This phenomenon has been largely ignored for application because only modest EC effects (2.6

Keywords: electrocaloric effect, thermoreflectance, ferroelectricity, cooling system

Procedia PDF Downloads 179
11553 Chemotactic Behaviour of Human Mesenchymal Stem Cells in Response to Silicate Substituted Hydroxyapatite

Authors: Dinara Ikramova, Karin A. Hing, Simon C. F. Rawlinson

Abstract:

Silicate-substituted hydroxyapatite (SiHA) has been shown to enhance bone regeneration in vivo compared with phase pure stoichiometric hydroxyapatite. Evidence suggests that substrate chemistry dependent formation of a permissive protein layer on the surface of synthetic bone graft substitute materials is key for bioactivity and cell attachment. However, little information is available on whether the substrate chemistry may affect cell migration and recruitment. The aim of this study is to investigate whether or not human Mesenchymal Stem Cells (hMSCs) exhibit a chemotactic response to SiHA porous granules and if it can be linked to either the ion exchange or protein sequestering and enrichment on the surface of the material. 150mg of SiHA granules with 80% total porosity and 20% strut porosity were incubated in 1ml of either Serum Free Media (SFM) or 10% Serum Containing Media (SCM) under static cell culture conditions (37°C, 5% CO2) in absence of cells. Protein sequestering and exchange of calcium, phosphate and silicate ions were analysed at 0.5, 1, 2, 4, 8, 16 and 24 hours with n=12 per time point. Migration of hMSCs in the presence of 150mg of SiHA granules was assessed over 24 hours using a modified transwell migration system in either SFM or SCM (n=6) with 30% serum containing media acting as a positive control. At 24 hours protein sequestering and ionic exchange were analysed, and the number of cells was quantified using a high throughput confocal microscope (IN Cell Analyser 6000). In acellular condition, both calcium and phosphate ion concentrations in media showed a decrease at 24 hours which was greater in SFM than in SCM. This suggests possible formation and precipitation of a bone like apatite on the surface of SiHA. Reduction in this activity observed in SCM indicates that the presence of serum proteins is interfering with the ion exchange at the material and media interface. Adsorbed protein levels showed fluctuation over time followed by sharp decrease at 24 hours, suggesting a possible protein rearrangement on the surface of the material. The ion analysis performed on SFM and SCM after 24-hour incubation with cells in the presence of granules showed a greater reduction in phosphate concentration in both SFM and SCM compared to phosphate levels in acellular condition. Silicate concentration in SCM increased from 1.6mM (absence of cells) to 5.1mM (presence of cells). This indicates that the cells are promoting the uptake of phosphate and release of silicate ions. No significant change was seen in levels of adsorbed proteins in the presence and absence of cells. Further analysis is required to determine whether the species of these proteins change over time. The analysis of cell migration after 24-hour incubation showed more cells migrating towards the granules, 12.7% in SFM and 8.3% in SCM, than in positive control, 4.5% in SFM and 3.6% in SCM respectively. These results suggest that SiHA has a chemotactic activity independent of serum proteins. A property which has not previously been demonstrated for a synthetic bone graft material.

Keywords: cell migration, hMSCs, SiHA, transwell migration system

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11552 Influence of Stacking Sequence and Temperature on Buckling Resistance of GFRP Infill Panel

Authors: Viriyavudh Sim, SeungHyun Kim, JungKyu Choi, WooYoung Jung

Abstract:

Glass Fiber Reinforced Polymer (GFRP) is a major evolution for energy dissipation when used as infill material for seismic retrofitting of steel frame, a basic PMC infill wall system consists of two GFRP laminates surrounding an infill of foam core. This paper presents numerical analysis in terms of buckling resistance of GFRP sandwich infill panels system under the influence of environment temperature and stacking sequence of laminate skin. Mode of failure under in-plane compression is studied by means of numerical analysis with ABAQUS platform. Parameters considered in this study are contact length between infill and frame, laminate stacking sequence of GFRP skin and variation of mechanical properties due to increment of temperature. The analysis is done with four cases of simple stacking sequence over a range of temperature. The result showed that both the effect of temperature and stacking sequence alter the performance of entire panel system. The rises of temperature resulted in the decrements of the panel’s strength. This is due to the polymeric nature of this material. Additionally, the contact length also displays the effect on the performance of infill panel. Furthermore, the laminate stiffness can be modified by orientation of laminate, which can increase the infill panel strength. Hence, optimal performance of the entire panel system can be obtained by comparing different cases of stacking sequence.

Keywords: buckling resistance, GFRP infill panel, stacking sequence, temperature dependent

Procedia PDF Downloads 372
11551 A Review: Global Crisis Effects on Agriculture and Animal Production in Turkey

Authors: Muhittin Fatih Demirhan, Sibel Alapala Demirhan

Abstract:

Agriculture, is also regarded as the primary activity area in all economies. When international comparisons are made Turkey has comparative advantages in agricultural potential. However, it is diffi cult to say that Turkey's agricultural productivity and use of technology is well developed in terms of sufficieny. Turkey, in terms of agricultural production, is one of the rare self-sufficient countries, but for supplying excessive demand of its domesticproduction to foreign markets to obtain the necessary income it is rather insufficient. On the basis of wrong policies implemented during the crisis and found that bottlenecks in agriculture and animal husbandry or agriculture policies of the IMF and World Bank are imposed on countries like Turkey. The IMF and the World Bank, the reduction of support in the agricultural and livestock Turkey, is known to put pressure for the abolition. Under these circumstances, our farmers, livestock producers and breeders of, not a chance to compete in the same market with EU producers. Animal products that capture the productivity levels of developed countries, seems to be our chance to compete with the quality and hygiene criteria. Thus, the discussion of the issue must be raised as for the sector's contribution to the economy in terms of further increasing production of the existing potential in mobilization.

Keywords: agricultural development, animal production, competition, economic crisis, food supply

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11550 Polymer Modification of Fine Grained Concretes Used in Textile Reinforced Cementitious Composites

Authors: Esma Gizem Daskiran, Mehmet Mustafa Daskiran, Mustafa Gencoglu

Abstract:

Textile reinforced cementitious composite (TRCC) is a development of a composite material where textile and fine-grained concrete (matrix) materials are used in combination. These matrices offer high performance properties in many aspects. To achieve high performance, polymer modified fine-grained concretes were used as matrix material which have high flexural strength. In this study, ten latex polymers and ten powder polymers were added to fine-grained concrete mixtures. These latex and powder polymers were added to the mixtures at different rates related to binder weight. Mechanical properties such as compressive and flexural strength were studied. Results showed that latex polymer and redispersible polymer modified fine-grained concretes showed different mechanical performance. A wide range of both latex and redispersible powder polymers were studied. As the addition rate increased compressive strength decreased for all mixtures. Flexural strength increased as the addition rate increased but significant enhancement was not observed through all mixtures.

Keywords: textile reinforced composite, cement, fine grained concrete, latex, redispersible powder

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11549 Designing Sustainable Building Based on Iranian's Windmills

Authors: Negar Sartipzadeh

Abstract:

Energy-conscious design, which coordinates with the Earth ecological systems during its life cycle, has the least negative impact on the environment with the least waste of resources. Due to the increasing in world population as well as the consumption of fossil fuels that cause the production of greenhouse gasses and environmental pollution, mankind is looking for renewable and also sustainable energies. The Iranian native construction is a clear evidence of energy-aware designing. Our predecessors were forced to rely on the natural resources and sustainable energies as well as environmental issues which have been being considered in the recent world. One of these endless energies is wind energy. Iranian traditional architecture foundations is a appropriate model in solving the environmental crisis and the contemporary energy. What will come in this paper is an effort to recognition and introduction of the unique characteristics of the Iranian architecture in the application of aerodynamic and hydraulic energies derived from the wind, which are the most common and major type of using sustainable energies in the traditional architecture of Iran. Therefore, the recent research attempts to offer a hybrid system suggestions for application in new constructions designing in a region such as Nashtifan, which has potential through reviewing windmills and how they deal with sustainable energy sources, as a model of Iranian native construction.

Keywords: renewable energy, sustainable building, windmill, Iranian architecture

Procedia PDF Downloads 417
11548 Characterization and Nanostructure Formation of Banana Peels Nanosorbent with Its Application

Authors: Opeyemi Atiba-Oyewo, Maurice S. Onyango, Christian Wolkersdorfer

Abstract:

Characterization and nanostructure formation of banana peels as sorbent material are described in this paper. The transformation of this agricultural waste via mechanical milling to enhance its properties such as changed in microstructure and surface area for water pollution control and other applications were studied. Mechanical milling was employed using planetary continuous milling machine with ethanol as a milling solvent and the samples were taken at time intervals between 10 h to 30 h to examine the structural changes. The samples were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red (FTIR), Transmission electron microscopy (TEM) and Brunauer Emmett and teller (BET). Results revealed three typical structures with different deformation mechanisms and the grain-sizes within the range of (71-12 nm), nanostructure of the particles and fibres. The particle size decreased from 65µm to 15 nm as the milling progressed for a period of 30 h. The morphological properties of the materials indicated that the particle shapes becomes regular and uniform as the milling progresses. Furthermore, particles fracturing resulted in surface area increment from 1.0694-4.5547 m2/g. The functional groups responsible for the banana peels capacity to coordinate and remove metal ions, such as the carboxylic and amine groups were identified at absorption bands of 1730 and 889 cm-1, respectively. However, the choice of this sorbent material for the sorption or any application will depend on the composition of the pollutant to be eradicated.

Keywords: characterization, nanostructure, nanosorbent, eco-friendly, banana peels, mechanical milling, water quality

Procedia PDF Downloads 281
11547 Influence of Recycled Polymer-Based Aggregates on Mechanical Properties of Polymer Concrete

Authors: Ahmet Kurklu, Abdussamed Sarp, Gokmen Arikan, Akin Eren, Arif Ulu, Ferit Cakir

Abstract:

Our natural resources are diminishing day by day with the needs of the growing world population. There is a danger that these resources will be depleted if they are not used in a controlled manner. As a result of the rapid increase in the consumption of limited natural resources, one of the issues where studies have gained importance is recycling. Many countries have carried out various research and development activities on recycling and reuse to prevent wastage of resources. For sustainable and healthy living, the limited amount of raw material resources in nature should be consumed consciously, and the necessary awareness should be given for recycling activities. One of the sectors where the consumption of raw materials is high is the construction sector. With the changing consumption habits of the evolving technology in the construction sector, the need to use special concrete along with the normal concrete has arisen. With the increasing need for specialty concretes, polymer concrete, which was discovered in the early 1900s, has evolved to the present day. Polymer concretes are special concretes with high strength, water impermeability, resistance to chemical action, and low surface roughness. Thanks to these properties, they find wide applications in many fields such as swimming pools, drainage systems, repair works. In the study, the effect of using recycled aggregates instead of natural aggregates in the production of polymer concrete on the performance of polymer concrete is investigated. In the experiments conducted for this purpose, the use of natural aggregate is reduced at certain rates, and instead, recycled aggregate is added at the same rate. The recycled aggregate to be used in the study is obtained from the polymer concrete drainage channel production facility of Mert Casting Co., Istanbul, Turkey. In order to clearly observe the effect of recycled materials on the product in the study, the other components (resin, hardener, accelerator, and additive) are kept constant in the concrete mix. In the study, fresh and hardened concrete tests are to be carried out on the mixes to be prepared.

Keywords: concrete, mechanical properties, polymer concrete, recycle aggregate

Procedia PDF Downloads 140
11546 Improving the Foult Ride through Capability and Stability of Wind Farms with DFIG Wind Turbine by Using Statcom

Authors: Abdulfetah Shobole, Arif Karakas, Ugur Savas Selamogullari, Mustafa Baysal

Abstract:

The concern of reducing emissions of Co2 from the fossil fuel generating units and using renewable energy sources increased in our world. Due this fact the integration ratio of wind farms to grid reached 20-30% in some part of our world. With increased integration of large MW scaled wind farms to the electric grid, the stability of the electrical system is a great concern. Thus, operators of power systems usually deman the wind turbine generators to obey the same rules as other traditional kinds of generation, such as thermal and hydro, i.e. not affect the grid stability. FACTS devices such as SVC or STATCOM are mostly installed close to the connection point of the wind farm to the grid in order to increase the stability especially during faulty conditions. In this paper wind farm with DFIG turbine type and STATCOM are dynamically modeled and simulated under three phase short circuit fault condition. The dynamic modeling is done by DigSILENT PowerFactory for the wind farm, STATCOM and the network. The simulation results show improvement of system stability near to the connection point of the STATCOM.

Keywords: DFIG wind turbine, statcom, dynamic modeling, digsilent

Procedia PDF Downloads 709