Search results for: cold formed
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2559

Search results for: cold formed

909 The Friendship Network Stability of Preschool Children during One Pedagogical Season

Authors: Yili Wang, Jarmo Kinos, Tuire Palonen, Tarja-Riitta Hurme

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This longitudinal study aims to examine how five- and six-year-old children’s peer relationships are formed and fostered during one preschool year in a southwestern Finnish preschool. All 16 kindergarteners participated in the study (at dyad level N=240; i.e., 16 x 15 relationships among the children). The children were divided into four daily groups, based on the table order during the daily routines, and four intervention groups, based on the teachers’ pedagogical plan. During the intervention, one iPad was given to each group in order to stimulate interaction among peers and, thus, enable the children to form new peer relationships. In the data gathering, sociometric nomination techniques were used to investigate the nature (i.e., stability and mutuality) of the peer relationships. The data was collected five times during the year to see what kind of peer relationship changes occurred at the dyad level and the group level, i.e., in establishing and losing friendship ties among the children. Social network analyses were used to analyze the data. The results indicate that the children’s preference for gender segregation was strong compared to age preference and intervention. In all, the number of reciprocal friendship ties and the mutual absence of friendship ties increased towards the end of the year, whereas the number of unilateral friendship ties decreased. This indicates that children’s nominations narrow down; thus, the group structure becomes more crystalized. Instead of extending their friendship networks, children seek stable and mutual relationships with their peers in their middle childhood years. The intervention only had a slightly negative influence on children’s peer relationships.

Keywords: intervention study, peer relationship, preschool education, social network analysis, sociometric ratings

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908 Construction of Submerged Aquatic Vegetation Index through Global Sensitivity Analysis of Radiative Transfer Model

Authors: Guanhua Zhou, Zhongqi Ma

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Submerged aquatic vegetation (SAV) in wetlands can absorb nitrogen and phosphorus effectively to prevent the eutrophication of water. It is feasible to monitor the distribution of SAV through remote sensing, but for the reason of weak vegetation signals affected by water body, traditional terrestrial vegetation indices are not applicable. This paper aims at constructing SAV index to enhance the vegetation signals and distinguish SAV from water body. The methodology is as follows: (1) select the bands sensitive to the vegetation parameters based on global sensitivity analysis of SAV canopy radiative transfer model; (2) take the soil line concept as reference, analyze the distribution of SAV and water reflectance simulated by SAV canopy model and semi-analytical water model in the two-dimensional space built by different sensitive bands; (3)select the band combinations which have better separation performance between SAV and water, and use them to build the SAVI indices in the form of normalized difference vegetation index(NDVI); (4)analyze the sensitivity of indices to the water and vegetation parameters, choose the one more sensitive to vegetation parameters. It is proved that index formed of the bands with central wavelengths in 705nm and 842nm has high sensitivity to chlorophyll content in leaves while it is less affected by water constituents. The model simulation shows a general negative, little correlation of SAV index with increasing water depth. Moreover, the index enhances capabilities in separating SAV from water compared to NDVI. The SAV index is expected to have potential in parameter inversion of wetland remote sensing.

Keywords: global sensitivity analysis, radiative transfer model, submerged aquatic vegetation, vegetation indices

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907 Numerical Simulation of Phase Transfer during Cryosurgery for an Irregular Tumor Using Hybrid Approach

Authors: Rama Bhargava, Surabhi Nishad

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The infusion of nanofluids has dramatically enhanced the heat-carrying capacity of the fluids, applicable to many engineering and medical process where the temperature below freezing is required. Cryosurgery is an efficient therapy for the treatment of cancer, but sometimes the excessive cooling may harm the nearby healthy cells. Efforts are therefore done to develop a model which can cause to generate the low temperature as required. In the present study, a mathematical model is developed based on the bioheat transfer equation to simulate the heat transfer from the probe on a tumor (with irregular domain) using the hybrid technique consisting of element free Galerkin method with αα-family of approximation. The probe is loaded will nano-particles. The effects of different nanoparticles, namely Al₂O₃, Fe₃O₄, Au on the heat-producing rate, is obtained. It is observed that the temperature can be brought to (60°C)-(-30°C) at a faster freezing rate on the infusion of different nanoparticles. Besides increasing the freezing rate, the volume of the nanoparticle can also control the size and growth of ice crystals formed during the freezing process. The study is also made to find the time required to achieve the desired temperature. The problem is further extended for multi tumors of different shapes and sizes. The irregular shape of the frozen domain and the direction of ice growth are very sensitive issues, posing a challenge for simulation. The Meshfree method has been one of the accurate methods in such problems as a domain is naturally irregular. The discretization is done using the nodes only. MLS approximation is taken in order to generate the shape functions. Sufficiently accurate results are obtained.

Keywords: cryosurgery, EFGM, hybrid, nanoparticles

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906 Overview Studies of High Strength Self-Consolidating Concrete

Authors: Raya Harkouss, Bilal Hamad

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Self-Consolidating Concrete (SCC) is considered as a relatively new technology created as an effective solution to problems associated with low quality consolidation. A SCC mix is defined as successful if it flows freely and cohesively without the intervention of mechanical compaction. The construction industry is showing high tendency to use SCC in many contemporary projects to benefit from the various advantages offered by this technology. At this point, a main question is raised regarding the effect of enhanced fluidity of SCC on the structural behavior of high strength self-consolidating reinforced concrete. A three phase research program was conducted at the American University of Beirut (AUB) to address this concern. The first two phases consisted of comparative studies conducted on concrete and mortar mixes prepared with second generation Sulphonated Naphtalene-based superplasticizer (SNF) or third generation Polycarboxylate Ethers-based superplasticizer (PCE). The third phase of the research program investigates and compares the structural performance of high strength reinforced concrete beam specimens prepared with two different generations of superplasticizers that formed the unique variable between the concrete mixes. The beams were designed to test and exhibit flexure, shear, or bond splitting failure. The outcomes of the experimental work revealed comparable resistance of beam specimens cast using self-compacting concrete and conventional vibrated concrete. The dissimilarities in the experimental values between the SCC and the control VC beams were minimal, leading to a conclusion, that the high consistency of SCC has little effect on the flexural, shear and bond strengths of concrete members.

Keywords: self-consolidating concrete (SCC), high-strength concrete, concrete admixtures, mechanical properties of hardened SCC, structural behavior of reinforced concrete beams

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905 Contribution of Spatial Teledetection to the Geological Mapping of the Imiter Buttonhole: Application to the Mineralized Structures of the Principal Corps B3 (CPB3) of the Imiter Mine (Anti-atlas, Morocco)

Authors: Bouayachi Ali, Alikouss Saida, Baroudi Zouhir, Zerhouni Youssef, Zouhair Mohammed, El Idrissi Assia, Essalhi Mourad

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The world-class Imiter silver deposit is located on the northern flank of the Precambrian Imiter buttonhole. This deposit is formed by epithermal veins hosted in the sandstone-pelite formations of the lower complex and in the basic conglomerates of the upper complex, these veins are controlled by a regional scale fault cluster, oriented N70°E to N90°E. The present work on the contribution of remote sensing on the geological mapping of the Imiter buttonhole and application to the mineralized structures of the Principal Corps B3. Mapping on satellite images is a very important tool in mineral prospecting. It allows the localization of the zones of interest in order to orientate the field missions by helping the localization of the major structures which facilitates the interpretation, the programming and the orientation of the mining works. The predictive map also allows for the correction of field mapping work, especially the direction and dimensions of structures such as dykes, corridors or scrapings. The use of a series of processing such as SAM, PCA, MNF and unsupervised and supervised classification on a Landsat 8 satellite image of the study area allowed us to highlight the main facies of the Imite area. To improve the exploration research, we used another processing that allows to realize a spatial distribution of the alteration mineral indices, and the application of several filters on the different bands to have lineament maps.

Keywords: principal corps B3, teledetection, Landsat 8, Imiter II, silver mineralization, lineaments

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904 Flow Sheet Development and Simulation of a Bio-refinery Annexed to Typical South African Sugar Mill

Authors: M. Ali Mandegari, S. Farzad, J. F. Görgens

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Sugar is one of the main agricultural industries in South Africa and approximately livelihoods of one million South Africans are indirectly dependent on sugar industry which is economically struggling with some problems and should re-invent in order to ensure a long-term sustainability. Second generation bio-refinery is defined as a process to use waste fibrous for the production of bio-fuel, chemicals animal food, and electricity. Bio-ethanol is by far the most widely used bio-fuel for transportation worldwide and many challenges in front of bio-ethanol production were solved. Bio-refinery annexed to the existing sugar mill for production of bio-ethanol and electricity is proposed to sugar industry and is addressed in this study. Since flow-sheet development is the key element of the bio-ethanol process, in this work, a bio-refinery (bio-ethanol and electricity production) annexed to a typical South African sugar mill considering 65ton/h dry sugarcane bagasse and tops/trash as feedstock was simulated. Aspen PlusTM V8.6 was applied as simulator and realistic simulation development approach was followed to reflect the practical behavior of the plant. Latest results of other researches considering pretreatment, hydrolysis, fermentation, enzyme production, bio-ethanol production and other supplementary units such as evaporation, water treatment, boiler, and steam/electricity generation units were adopted to establish a comprehensive bio-refinery simulation. Steam explosion with SO2 was selected for pretreatment due to minimum inhibitor production and simultaneous saccharification and fermentation (SSF) configuration was adopted for enzymatic hydrolysis and fermentation of cellulose and hydrolyze. Bio-ethanol purification was simulated by two distillation columns with side stream and fuel grade bio-ethanol (99.5%) was achieved using molecular sieve in order to minimize the capital and operating costs. Also boiler and steam/power generation were completed using industrial design data. Results indicates 256.6 kg bio ethanol per ton of feedstock and 31 MW surplus power were attained from bio-refinery while the process consumes 3.5, 3.38, and 0.164 (GJ/ton per ton of feedstock) hot utility, cold utility and electricity respectively. Developed simulation is a threshold of variety analyses and developments for further studies.

Keywords: bio-refinery, bagasse, tops, trash, bio-ethanol, electricity

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903 Analysis of Network Connectivity for Ship-To-Ship Maritime Communication Using IEEE 802.11 on Maritime Environment of Tanjung Perak, Indonesia

Authors: Ahmad Fauzi Makarim, Okkie Puspitorini, Hani'ah Mahmudah, Nur Adi Siswandari, Ari Wijayanti

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As a maritime country, Indonesia needs a solution in maritime connectivity which can assist the maritime communication system which including communication from harbor to the ship or ship to ship. The needs of many application services for maritime communication, whether for safety reasons until voyage service to help the process of voyage activity needs connection with a high bandwith. To support the government efforts in handling that kind of problem, a research is conducted in maritime communication issue by applying the new developed technology in Indonesia, namely IEEE 802.11. In this research, 3 outdoor WiFi devices are used in which have a frequency of 5.8 GHz. Maritime of Tanjung Perak harbor in Surabaya until Karang Jamuang Island are used as the location of the research with defining permission of ship node spreading by Navigation District Class 1. That maritime area formed by state 1 and state 2 areas which are the narrow area with average wave height of 0.7 meter based on the data from BMKG S urabaya. After that, wave height used as one of the parameters which are used in analyzing characteristic of signal propagation at sea surface, so it can be determined on the coverage area of transmitter system. In this research has been used three samples of outdoor wifi, there is the coverage of device A can be determined about 2256 meter, device B 4000 meter, and device C 1174 meter. Then to analyze of network connectivity for the ship to ship is used AODV routing algorithm system based on the value of the power transmit was smallest of all nodes within the transmitter coverage.

Keywords: maritime of Indonesia, maritime communications, outdoor wifi, coverage, AODV

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902 The Amorphousness of the Exposure Sphere

Authors: Nipun Ansal

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People guard their beliefs and opinions with their lives. Beliefs that they’ve formed over a period of time, and can go to any lengths to defy, desist from, resist and negate any outward stimulus that has the potential to shake them. Cognitive dissonance is term used to describe it in theory. And every human being, in order to defend himself from cognitive dissonance applies 4 rings of defense viz. Selective Exposure, Selective Perception, Selective Attention, and Selective Retention. This paper is a discursive analysis on how the onslaught of social media, complete with its intrusive weaponry, has amorphized the external ring of defense: the selective exposure. The stimulus-response model of communication is one of the most inherent model that encompasses communication behaviours of children and elderly, individual and masses, humans and animals alike. The paper deliberates on how information bombardment through the uncontrollable channels of the social media, Facebook and Twitter in particular, have dismantled our outer sphere of exposure, leading users online to a state of constant dissonance, and thus feeding impulsive action-taking. It applies case study method citing an example to corroborate how knowledge generation has given in to the information overload and the effect it has on decision making. With stimulus increasing in number of encounters, opinion formation precedes knowledge because of the increased demand of participation and decrease in time for the information to permeate from the outer sphere of exposure to the sphere of retention, which of course, is through perception and attention. This paper discusses the challenge posed by this fleeting, stimulus rich, peer-dominated media on the traditional models of communication and meaning-generation.

Keywords: communication, discretion, exposure, social media, stimulus

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901 Polymer Nanostructures Based Catalytic Materials for Energy and Environmental Applications

Authors: S. Ghosh, L. Ramos, A. N. Kouamé, A.-L. Teillout, H. Remita

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Catalytic materials have attracted continuous attention due to their promising applications in a variety of energy and environmental applications including clean energy, energy conversion and storage, purification and separation, degradation of pollutants and electrochemical reactions etc. With the advanced synthetic technologies, polymer nanostructures and nanocomposites can be directly synthesized through soft template mediated approach using swollen hexagonal mesophases and modulate the size, morphology, and structure of polymer nanostructures. As an alternative to conventional catalytic materials, one-dimensional PDPB polymer nanostructures shows high photocatalytic activity under visible light for the degradation of pollutants. These photocatalysts are very stable with cycling. Transmission electron microscopy (TEM), and AFM-IR characterizations reveal that the morphology and structure of the polymer nanostructures do not change after photocatalysis. These stable and cheap polymer nanofibers and metal polymer nanocomposites are easy to process and can be reused without appreciable loss of activity. The polymer nanocomposites formed via one pot chemical redox reaction with 3.4 nm Pd nanoparticles on poly(diphenylbutadiyne) (PDPB) nanofibers (30 nm). The reduction of Pd (II) ions is accompanied by oxidative polymerization leading to composites materials. Hybrid Pd/PDPB nanocomposites used as electrode materials for the electrocatalytic oxidation of ethanol without using support of proton exchange Nafion membrane. Hence, these conducting polymer nanofibers and nanocomposites offer the perspective of developing a new generation of efficient photocatalysts for environmental protection and in electrocatalysis for fuel cell applications.

Keywords: conducting polymer, swollen hexagonal mesophases, solar photocatalysis, electrocatalysis, water depollution

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900 Creation of Ultrafast Ultra-Broadband High Energy Laser Pulses

Authors: Walid Tawfik

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The interaction of high intensity ultrashort laser pulses with plasma generates many significant applications, including soft x-ray lasers, time-resolved laser induced plasma spectroscopy LIPS, and laser-driven accelerators. The development in producing of femtosecond down to ten femtosecond optical pulses has facilitates scientists with a vital tool in a variety of ultrashort phenomena, such as high field physics, femtochemistry and high harmonic generation HHG. In this research, we generate a two-octave-wide ultrashort supercontinuum pulses with an optical spectrum extending from 3.5 eV (ultraviolet) to 1.3 eV (near-infrared) using a capillary fiber filled with neon gas. These pulses are formed according to nonlinear self-phase modulation in the neon gas as a nonlinear medium. The investigations of the created pulses were made using spectral phase interferometry for direct electric-field reconstruction (SPIDER). A complete description of the output pulses was considered. The observed characterization of the produced pulses includes the beam profile, the pulse width, and the spectral bandwidth. After reaching optimization conditions, the intensity of the reconstructed pulse autocorrelation function was applied for the shorts pulse duration to achieve transform limited ultrashort pulses with durations below 6-fs energies up to 600μJ. Moreover, the effect of neon pressure variation on the pulse width was examined. The nonlinear self-phase modulation realized to be increased with the pressure of the neon gas. The observed results may lead to an advanced method to control and monitor ultrashort transit interaction in femtochemistry.

Keywords: supercontinuum, ultrafast, SPIDER, ultra-broadband

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899 Artificial Intelligence in Bioscience: The Next Frontier

Authors: Parthiban Srinivasan

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With recent advances in computational power and access to enough data in biosciences, artificial intelligence methods are increasingly being used in drug discovery research. These methods are essentially a series of advanced statistics based exercises that review the past to indicate the likely future. Our goal is to develop a model that accurately predicts biological activity and toxicity parameters for novel compounds. We have compiled a robust library of over 150,000 chemical compounds with different pharmacological properties from literature and public domain databases. The compounds are stored in simplified molecular-input line-entry system (SMILES), a commonly used text encoding for organic molecules. We utilize an automated process to generate an array of numerical descriptors (features) for each molecule. Redundant and irrelevant descriptors are eliminated iteratively. Our prediction engine is based on a portfolio of machine learning algorithms. We found Random Forest algorithm to be a better choice for this analysis. We captured non-linear relationship in the data and formed a prediction model with reasonable accuracy by averaging across a large number of randomized decision trees. Our next step is to apply deep neural network (DNN) algorithm to predict the biological activity and toxicity properties. We expect the DNN algorithm to give better results and improve the accuracy of the prediction. This presentation will review all these prominent machine learning and deep learning methods, our implementation protocols and discuss these techniques for their usefulness in biomedical and health informatics.

Keywords: deep learning, drug discovery, health informatics, machine learning, toxicity prediction

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898 Effect of Iron Oxide Addition on the Solid-State Synthesis of Ye’Elimite

Authors: F. Z. Abir, M. Mesnaoui, Y. Abouliatim, L. Nibou, Y. El Hafiane, A. Smith

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The cement industry has been taking significant steps for years to reduce its carbon footprint by opting for an eco-friendly alternative such as Calcium Sulfoaluminate Cements (CSA). These binders, compared to Ordinary Portland Cements (OPC), have two advantages: reduction of the CO2 emissions and energy-saving because the sintering temperature of CSA cements is between 1250 and 1350 °C, which means 100 to 200 °C less than OPC. The aim of this work is to study the impurities effect, such as iron oxide, on the formation of the ye'elimite phase, which represents the main phase of Calcium Sulfoaluminate Cements and the consequence on its hydration. Several elaborations and characterization techniques were used to study the structure and microstructure of ye'elimite, such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), thermal analysis, specific surface area measurement, and electrical conductivity of diluted solutions. This study details the protocol for the solid-state synthesis of ye'elimite containing increasing amounts of iron (general formula: Ca4Al(6-2x)Fe2xSO16 with x = 0.00 to 1.13). Ye'elimite is formed by solid-state reactions between Al2O3, CaO and CaSO4 and the maximum ye'elimite content is reached at a sintering temperature of 1300 °C. The presence of iron promotes the formation of cubic ye'elimite at the expense of the orthorhombic phase. The total incorporation of iron in ye'elimite structure is possible when x < 0.12. Beyond this content, the ferritic phase (CaO)2(Al2O3,Fe2O3) appears as a minor phase and develops two different morphologies during cooling: dendritic crystals and melt morphology. The formation of the ferrous liquid phase affects the evolution of grain size of the ye’elimite and calcium aluminates.

Keywords: calcium sulfoaluminate cement, ferritic phase, sintering, solid-state synthesis, ye’elimite

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897 Analysis and Control of Camera Type Weft Straightener

Authors: Jae-Yong Lee, Gyu-Hyun Bae, Yun-Soo Chung, Dae-Sub Kim, Jae-Sung Bae

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In general, fabric is heat-treated using a stenter machine in order to dry and fix its shape. It is important to shape before the heat treatment because it is difficult to revert back once the fabric is formed. To produce the product of right shape, camera type weft straightener has been applied recently to capture and process fabric images quickly. It is more powerful in determining the final textile quality rather than photo-sensor. Positioning in front of a stenter machine, weft straightener helps to spread fabric evenly and control the angle between warp and weft constantly as right angle by handling skew and bow rollers. To process this tricky procedure, the structural analysis should be carried out in advance, based on which, its control technology can be drawn. A structural analysis is to figure out the specific contact/slippage characteristics between fabric and roller. We already examined the applicability of camera type weft straightener to plain weave fabric and found its possibility and the specific working condition of machine and rollers. In this research, we aimed to explore another applicability of camera type weft straightener. Namely, we tried to figure out camera type weft straightener can be used for fabrics. To find out the optimum condition, we increased the number of rollers. The analysis is done by ANSYS software using Finite Element Analysis method. The control function is demonstrated by experiment. In conclusion, the structural analysis of weft straightener is done to identify a specific characteristic between roller and fabrics. The control of skew and bow roller is done to decrease the error of the angle between warp and weft. Finally, it is proved that camera type straightener can also be used for the special fabrics.

Keywords: camera type weft straightener, structure analysis, control, skew and bow roller

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896 An Initial Evaluation of Newly Proposed Biomarker of Zinc Status in Humans: The Erythrocyte Linoleic Acid: Dihomo-γ-Linolenic Acid (LA:DGLA) Ratio

Authors: Marija Knez, James C.R. Stangoulis, Manja Zec, Zoran Pavlovic, Jasmina D. Martacic, Mirjana Gurinovic, Maria Glibetic

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Background: Zinc is an essential micronutrient for humans with important physiological functions. A sensitive and specific biomarker for assessing Zn status is still needed. Objective: The major aim of this study was to examine if the changes in the content of plasma phospholipid LA, DGLA and LA: DGLA ratio can be used to efficiently predict the dietary Zn intake and plasma Zn status of humans. Methods: The study was performed on apparently healthy human volunteers. The dietary Zn intake was assessed using 24h recall questionnaires. Plasma phospholipid fatty acid analysis was done by gas chromatography and plasma analysis of minerals by atomic absorption spectrometry. Biochemical, anthropometrical and hematological parameters were assessed. Results: No significant relationship was found between the dietary and plasma zinc status (r=0.07; p=0.6). There is a statistically significant correlation between DGLA and plasma Zn (r=0.39, p=0.00). No relationship was observed between the linoleic acid and plasma Zn, while there was a significant negative correlation between LA: DGLA ratio and plasma Zn status (r=-0.35, p=0.01). Similarly, there were statistically significant difference in DGLA status (p=0.004) and LA: DGLA ratio (p=0.042) between the Zn formed groups. Conclusions: This study is an initial step in evaluating LA: DGLA ratio as a biomarker of Zn status in humans. The results are encouraging as they show that concentration of DGLA is decreased and LA: DGLA ratio increased in people with lower dietary Zn intake. However, additional studies are needed to fully examine the sensitivity of this biomarker.

Keywords: dietary Zn intake Zinc, fatty acid composition, LA: DGLA, healthy population, plasma Zn status, Zn biomarker

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895 Carbon Dioxide Removal from Off Gases in a Self-Priming Submerged Venturi Scrubber

Authors: Manisha Bal, Amit Verma, B. C. Meikap

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Carbon dioxide (CO₂) is the most abundant waste produced by human activities. It is estimated to be one of the major contributors of greenhouse effect and also considered as a major air pollutant formed by burning of fossil fuels. The main sources of emissions are flue gas from thermal power plants and process industries. It is also a contributor of acid rain. Its exposure through inhalation can lead to health risks. Therefore, control of CO₂ emission in the environment is very necessary. The main focus of this study is on the removal of carbon dioxide from off gases using a self-priming venturi scrubber in submerged conditions using sodium hydroxide as the scrubbing liquid. A self-priming submerged venturi scrubber is an efficient device to remove gaseous pollutants. In submerged condition, venturi scrubber remains submerged in the liquid tank and the liquid enters at the throat section of venturi scrubber due to the pressure difference which includes the hydrostatic pressure of the liquid and static pressure of the gas. The inlet polluted air stream enters through converging section which moves at very high velocity in the throat section and atomizes the liquid droplets. This leads to absorption of CO₂ from the off gases in scrubbing liquid which resulted in removal of CO₂ gas from the off gases. Detailed investigation on the scrubbing of carbon dioxide has been done in this literature. Experiments were conducted at different throat gas velocities, liquid levels in outer cylinder and CO₂ inlet concentrations to study the carbon dioxide removal efficiency. Experimental results give more than 95% removal efficiency of CO₂ in the self priming venturi scrubber which can meet the environmental emission limit of CO₂ to save the human life.

Keywords: carbon dioxide, scrubbing, pollution control, self-priming venturi scrubber

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894 Spatial and Geostatistical Analysis of Surficial Soils of the Contiguous United States

Authors: Rachel Hetherington, Chad Deering, Ann Maclean, Snehamoy Chatterjee

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The U.S. Geological Survey conducted a soil survey and subsequent mineralogical and geochemical analyses of over 4800 samples taken across the contiguous United States between the years 2007 and 2013. At each location, samples were taken from the top 5 cm, the A-horizon, and the C-horizon. Many studies have looked at the correlation between the mineralogical and geochemical content of soils and influencing factors such as parent lithology, climate, soil type, and age, but it seems little has been done in relation to quantifying and assessing the correlation between elements in the soil on a national scale. GIS was used for the mapping and multivariate interpolation of over 40 major and trace elements for surficial soils (0-5 cm depth). Qualitative analysis of the spatial distribution across the U.S. shows distinct patterns amongst elements both within the same periodic groups and within different periodic groups, and therefore with different behavioural characteristics. Results show the emergence of 4 main patterns of high concentration areas: vertically along the west coast, a C-shape formed through the states around Utah and northern Arizona, a V-shape through the Midwest and connecting to the Appalachians, and along the Appalachians. The Band Collection Statistics tool in GIS was used to quantitatively analyse the geochemical raster datasets and calculate a correlation matrix. Patterns emerged, which were not identified in qualitative analysis, many of which are also amongst elements with very different characteristics. Preliminary results show 41 element pairings with a strong positive correlation ( ≥ 0.75). Both qualitative and quantitative analyses on this scale could increase knowledge on the relationships between element distribution and behaviour in surficial soils of the U.S.

Keywords: correlation matrix, geochemical analyses, spatial distribution of elements, surficial soils

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893 The Lived Experience of Caregiving as a Vulnerable Person: Preliminary Findings of an Applied Hermeneutic Phenomenology Study

Authors: Amanda Aliende da Matta

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In different fields, there are people who have something that stands out. In the educational world, for example, it is clear when some teachers have something: they are the best teachers, but this is not directly attributed to their disciplines, methodologies, etc. It is that they have something that captivates, inspires, and motivates. But we also find this something in other contexts. In this thesis, the interest is in something that some marginalized people, such as Ab (fictitious name), have. Ab was born in a rural community and saw the lifestyle of his family change drastically as a consequence of structural changes in his village. The community became impoverished, and together with a group of teenagers, he decided to migrate to Spain in search of opportunities. His best friend drowned during the crossing. After arriving, he lived in indecent conditions and felt unsafe. He now suffers from anxiety and frequently faints from it. Yet, he’s linked to Joves x la pau (a Christian project, although he is a Muslim), distributing food for people who live on the streets every Thursday afternoon. When he asked about what happens on cold and rainy days, he explained simply: "if it rains, I distribute the food, and immediately I get home, take a bath, and sleep warm under my roof. That is when we most have to go." This something he has will be called caring. And one of the general objectives of the thesis is to discover what are the meaning structures of this caring what is the lived experience of this caring. In this communication, preliminary results of an Applied Hermeneutic Phenomenology (AHP) study on the lived experience of caring as a vulnerable person are presented. The research means to answer what is the lived experience of caring as a vulnerable person. That is, to describe and explain what it is like to caregive for a vulnerable person, what it is, essentially, to caregive for a vulnerable person, what makes the lived experience of caregiving for a vulnerable person different from any other. In order to investigate the meaning of the phenomenon of caregiving as a vulnerable person, as already stated, the method used will be Applied Hermeneutic Phenomenology (AHP). We base ourselves, initially, on the proposal of Raquel Ayala-Carabajo and Max Van Manen. As Van Manen (1990) explains, AHP is a method that works essentially through fieldwork, with the collection of data on lived experience (experiential material). It is a phenomenology of practice. We here present the provisional themes we found: caregiving as a vulnerable person is seeing yourself in the other, identifying with the care-receiver; Caregiving as a vulnerable person is putting the other’s need before oneself’s; Caregiving as a vulnerable person is temporarily overcoming your weaknesses to make yourself strong for the other; Caregiving as a vulnerable person is going beyond the conventional approach; and Caregiving as a vulnerable person is taking responsibility even if it’s not yours.

Keywords: applied hermeneutic phenomenology, care ethics, hermeneutics, phenomenology

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892 Impact of Climate Variability on Household's Crop Income in Central Highlands and Arssi Grain Plough Areas of Ethiopia

Authors: Arega Shumetie Ademe, Belay Kassa, Degye Goshu, Majaliwa Mwanjalolo

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Currently the world economy is suffering from one critical problem, climate change. Some studies done before identified that impact of the problem is region specific means in some part of the world (temperate zone) there is improvement in agricultural performance but in some others like in the tropics there is drastic reduction in crop production and crop income. Climate variability is becoming dominant cause of short-term fluctuation in rain-fed agricultural production and income of developing countries. The purely rain-fed Ethiopian agriculture is the most vulnerable sector to the risks and impacts of climate variability. Thus, this study tried to identify impact of climate variability on crop income of smallholders in Ethiopia. The research used eight rounded unbalanced panel data from 1994- 2014 collected from six villages in the study area. After having all diagnostic tests the research used fixed effect method of regression. Based on the regression result rainfall and temperature deviation from their respective long term averages have negative and significant effect on crop income. Other extreme devastating shocks like flood, storm and frost, which are sourced from climate variability, have significant and negative effect on crop income of households’. Parameters that notify rainfall inconsistency like late start, variation in availability at growing season, and early cessation are critical problems for crop income of smallholder households as to the model result. Given this, impact of climate variability is not consistent in different agro-ecologies of the country. Rainfall variability has similar impact on crop income in different agro-ecology, but variation in temperature affects cold agro-ecology villages negatively and significantly, while it has positive effect in warm villages. Parameters that represent rainfall inconsistency have similar impact in both agro-ecologies and the aggregate model regression. This implies climate variability sourced from rainfall inconsistency is the main problem of Ethiopian agriculture especially the crop production sub-sector of smallholder households.

Keywords: climate variability, crop income, household, rainfall, temperature

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891 Mechanical, Thermal and Biodegradable Properties of Bioplast-Spruce Green Wood Polymer Composites

Authors: A. Atli, K. Candelier, J. Alteyrac

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Environmental and sustainability concerns push the industries to manufacture alternative materials having less environmental impact. The Wood Plastic Composites (WPCs) produced by blending the biopolymers and natural fillers permit not only to tailor the desired properties of materials but also are the solution to meet the environmental and sustainability requirements. This work presents the elaboration and characterization of the fully green WPCs prepared by blending a biopolymer, BIOPLAST® GS 2189 and spruce sawdust used as filler with different amounts. Since both components are bio-based, the resulting material is entirely environmentally friendly. The mechanical, thermal, structural properties of these WPCs were characterized by different analytical methods like tensile, flexural and impact tests, Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and X-ray Diffraction (XRD). Their water absorption properties and resistance to the termite and fungal attacks were determined in relation with different wood filler content. The tensile and flexural moduli of WPCs increased with increasing amount of wood fillers into the biopolymer, but WPCs became more brittle compared to the neat polymer. Incorporation of spruce sawdust modified the thermal properties of polymer: The degradation, cold crystallization, and melting temperatures shifted to higher temperatures when spruce sawdust was added into polymer. The termite, fungal and water absorption resistance of WPCs decreased with increasing wood amount in WPCs, but remained in durability class 1 (durable) concerning fungal resistance and quoted 1 (attempted attack) in visual rating regarding to the termites resistance except that the WPC with the highest wood content (30 wt%) rated 2 (slight attack) indicating a long term durability. All the results showed the possibility to elaborate the easy injectable composite materials with adjustable properties by incorporation of BIOPLAST® GS 2189 and spruce sawdust. Therefore, lightweight WPCs allow both to recycle wood industry byproducts and to produce a full ecologic material.

Keywords: biodegradability, color measurements, durability, mechanical properties, melt flow index, MFI, structural properties, thermal properties, wood-plastic composites, WPCs

Procedia PDF Downloads 125
890 Aseismic Stiffening of Architectural Buildings as Preventive Restoration Using Unconventional Materials

Authors: Jefto Terzovic, Ana Kontic, Isidora Ilic

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In the proposed design concept, laminated glass and laminated plexiglass, as ”unconventional materials”, are considered as a filling in a steel frame on which they overlap by the intermediate rubber layer, thereby forming a composite assembly. In this way vertical elements of stiffening are formed, capable for reception of seismic force and integrated into the structural system of the building. The applicability of such a system was verified by experiments in laboratory conditions where the experimental models based on laminated glass and laminated plexiglass had been exposed to the cyclic loads that simulate the seismic force. In this way the load capacity of composite assemblies was tested for the effects of dynamic load that was parallel to assembly plane. Thus, the stress intensity to which composite systems might be exposed was determined as well as the range of the structure stiffening referring to the expressed deformation along with the advantages of a particular type of filling compared to the other one. Using specialized software whose operation is based on the finite element method, a computer model of the structure was created and processed in the case study; the same computer model was used for analyzing the problem in the first phase of the design process. The stiffening system based on composite assemblies tested in laboratories is implemented in the computer model. The results of the modal analysis and seismic calculation from the computer model with stiffeners applied showed an efficacy of such a solution, thus rounding the design procedures for aseismic stiffening by using unconventional materials.

Keywords: laminated glass, laminated plexiglass, aseismic stiffening, experiment, laboratory testing, computer model, finite element method

Procedia PDF Downloads 65
889 Combined Power Supply at Well Drilling in Extreme Climate Conditions

Authors: V. Morenov, E. Leusheva

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Power supplying of well drilling on oil and gas fields at ambient air low temperatures is characterized by increased requirements of electric and heat energy. Power costs for heating of production facilities, technological and living objects may several times exceed drilling equipment electric power consumption. Power supplying of prospecting and exploitation drilling objects is usually done by means of local electric power structures based on diesel power stations. In the meantime, exploitation of oil fields is accompanied by vast quantities of extracted associated petroleum gas, and while developing gas fields there are considerable amounts of natural gas and gas condensate. In this regard implementation of gas-powered self-sufficient power units functioning on produced crude products for power supplying is seen as most potential. For these purposes gas turbines (GT) or gas reciprocating engines (GRE) may be used. In addition gas-powered units are most efficiently used in cogeneration mode - combined heat and power production. Conducted research revealed that GT generate more heat than GRE while producing electricity. One of the latest GT design are microturbines (MT) - devices that may be efficiently exploited in combined heat and power mode. In conditions of ambient air low temperatures and high velocity wind sufficient heat supplying is required for both technological process, specifically for drilling mud heating, and for maintaining comfortable working conditions at the rig. One of the main heat regime parameters are the heat losses. Due to structural peculiarities of the rig most of the heat losses occur at cold air infiltration through the technological apertures and hatchways and heat transition of isolation constructions. Also significant amount of heat is required for working temperature sustaining of the drilling mud. Violation of circulation thermal regime may lead to ice build-up on well surfaces and ice blockages in armature elements. That is why it is important to ensure heating of the drilling mud chamber according to ambient air temperature. Needed heat power will be defined by heat losses of the chamber. Noting heat power required for drilling structure functioning, it is possible to create combined heat and power complex based on MT for satisfying consumer power needs and at the same time lowering power generation costs. As a result, combined power supplying scheme for multiple well drilling utilizing heat of MT flue gases was developed.

Keywords: combined heat, combined power, drilling, electric supply, gas-powered units, heat supply

Procedia PDF Downloads 566
888 ANSYS FLUENT Simulation of Natural Convection and Radiation in a Solar Enclosure

Authors: Sireetorn Kuharat, Anwar Beg

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In this study, multi-mode heat transfer characteristics of spacecraft solar collectors are investigated computationally. Two-dimensional steady-state incompressible laminar Newtonian viscous convection-radiative heat transfer in a rectangular solar collector geometry. The ANSYS FLUENT finite volume code (version 17.2) is employed to simulate the thermo-fluid characteristics. Several radiative transfer models are employed which are available in the ANSYS workbench, including the classical Rosseland flux model and the more elegant P1 flux model. Mesh-independence tests are conducted. Validation of the simulations is conducted with a computational Harlow-Welch MAC (Marker and Cell) finite difference method and excellent correlation. The influence of aspect ratio, Prandtl number (Pr), Rayleigh number (Ra) and radiative flux model on temperature, isotherms, velocity, the pressure is evaluated and visualized in color plots. Additionally, the local convective heat flux is computed and solutions are compared with the MAC solver for various buoyancy effects (e.g. Ra = 10,000,000) achieving excellent agreement. The P1 model is shown to better predict the actual influence of solar radiative flux on thermal fluid behavior compared with the limited Rosseland model. With increasing Rayleigh numbers the hot zone emanating from the base of the collector is found to penetrate deeper into the collector and rises symmetrically dividing into two vortex regions with very high buoyancy effect (Ra >100,000). With increasing Prandtl number (three gas cases are examined respectively hydrogen gas mixture, air and ammonia gas) there is also a progressive incursion of the hot zone at the solar collector base higher into the solar collector space and simultaneously a greater asymmetric behavior of the dual isothermal zones. With increasing aspect ratio (wider base relative to the height of the solar collector geometry) there is a greater thermal convection pattern around the whole geometry, higher temperatures and the elimination of the cold upper zone associated with lower aspect ratio.

Keywords: thermal convection, radiative heat transfer, solar collector, Rayleigh number

Procedia PDF Downloads 103
887 Assessing the Feasibility of Commercial Meat Rabbit Production in the Kumasi Metropolis of Ghana

Authors: Nana Segu Acquaah-Harrison, James Osei Mensah, Richard Aidoo, David Amponsah, Amy Buah, Gilbert Aboagye

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The study aimed at assessing the feasibility of commercial meat rabbit production in the Kumasi Metropolis of Ghana. Structured and unstructured questionnaires were utilized in obtaining information from two hundred meat consumers and 15 meat rabbit farmers. Data were analyzed using Net Present Value (NPV), Internal Rate of Return (IRR), Benefit Cost Ratio (BCR)/Profitability Index (PI) technique, percentages and chi-square contingency test. The study found that the current demand for rabbit meat is low (36%). The desirable nutritional attributes of rabbit meat and other socio economic factors of meat consumers make the potential demand for rabbit meat high (69%). It was estimated that GH¢5,292 (approximately $ 2672) was needed as a start-up capital for a 40-doe unit meat rabbit farm in Kumasi Metropolis. The cost of breeding animals, housing and equipment formed 12.47%, 53.97% and 24.87% respectively of the initial estimated capital. A Net Present Value of GH¢ 5,910.75 (approximately $ 2984) was obtained at the end of the fifth year, with an internal rate return and profitability index of 70% and 1.12 respectively. The major constraints identified in meat rabbit production were low price of rabbit meat, shortage of fodder, pest and diseases, high cost of capital, high cost of operating materials and veterinary care. Based on the analysis, it was concluded that meat rabbit production is feasible in the Kumasi Metropolis of Ghana. The study recommends embarking on mass advertisement; farmer association and adapting to new technologies in the production process will help to enhance productivity.

Keywords: feasibility, commercial meat rabbit, production, Kumasi, Ghana

Procedia PDF Downloads 111
886 A Morphological Examination of Urban Renewal Processes: The Sample of Konya City

Authors: Muzaffer Ali Yaygın, Mehmet Topçu

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This research aims to investigate morphological changes in urban patterns in urban renewal areas by using geographic information systems and to reveal pattern differences that occur before and after urban renewal processes by applying a morphological analysis. The concept of urban morphology is not involved in urban renewal and urban planning practices in Turkey. This situation destroys the structural characteristic of urban space which appears as a consequence of changes at city, street or plot level. Different approaches and renewal interventions to urban settlements, which are formed as a reflection of cultural issues, may have positive and negative results. A morphological analysis has been applied to an urban renewal area that covers 325 ha. in Konya, in which city urban renewal projects have gained speed with the increasing of economic investments in this study. The study mentions urban renewal and urban morphology relationship, varied academic approach on the urban morphology issue, urban morphology components, changes in lots pattern and numerical differences that occur on road, construction and green space ratios that are before and after the renewal project, and the results of the morphological analysis. It is seen that the built-up area has significant differences when compared to the previous situation. The amount of green areas decreased significantly in quantitative terms; the transportation systems has been changed completely; and the property ownership has been reconstructed without taking the previous situation into account. Findings show that urban renewal projects in Turkey are put into practice with a rent-oriented approach without making an in-depth analysis. The paper discusses the morphological dimension of urban renewal projects in Turkey through a case study from Konya city.

Keywords: Konya, pattern, urban morphology, urban renewal

Procedia PDF Downloads 347
885 Microstructure Evolution and Pre-transformation Microstructure Reconstruction in Ti-6Al-4V Alloy

Authors: Shreyash Hadke, Manendra Singh Parihar, Rajesh Khatirkar

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In the present investigation, the variation in the microstructure with the changes in the heat treatment conditions i.e. temperature and time was observed. Ti-6Al-4V alloy was subject to solution annealing treatments in β (1066C) and α+β phase (930C and 850C) followed by quenching, air cooling and furnace cooling to room temperature respectively. The effect of solution annealing and cooling on the microstructure was studied by using optical microscopy (OM), scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and x-ray diffraction (XRD). The chemical composition of the β phase for different conditions was determined with the help of energy dispersive spectrometer (EDS) attached to SEM. Furnace cooling resulted in the development of coarser structure (α+β), while air cooling resulted in much finer structure with widmanstatten morphology of α at the grain boundaries. Quenching from solution annealing temperature formed α’ martensite, their proportion being dependent on the temperature in β phase field. It is well known that the transformation of β to α follows Burger orientation relationship (OR). In order to reconstruct the microstructure of parent β phase, a MATLAB code was written using neighbor-to-neighbor, triplet method and Tari’s method. The code was tested on the annealed samples (1066C solution annealing temperature followed by furnace cooling to room temperature). The parent phase data thus generated was then plotted using the TSL-OIM software. The reconstruction results of the above methods were compared and analyzed. The Tari’s approach (clustering approach) gave better results compared to neighbor-to-neighbor and triplet method but the time taken by the triplet method was least compared to the other two methods.

Keywords: Ti-6Al-4V alloy, microstructure, electron backscattered diffraction, parent phase reconstruction

Procedia PDF Downloads 433
884 Electrochemical Modification of Boron Doped Carbon Nanowall Electrodes for Biosensing Purposes

Authors: M. Kowalski, M. Brodowski, K. Dziabowska, E. Czaczyk, W. Bialobrzeska, N. Malinowska, S. Zoledowska, R. Bogdanowicz, D. Nidzworski

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Boron-doped-carbon nanowall (BCNW) electrodes are recently in much interest among scientists. BCNWs are good candidates for biosensor purposes as they possess interesting electrochemical characteristics like a wide potential range and the low difference between redox peaks. Moreover, from technical parameters, they are mechanically resistant and very tough. The production process of the microwave plasma-enhanced chemical vapor deposition (MPECVD) allows boron to build into the structure of the diamond being formed. The effect is the formation of flat, long structures with sharp ends. The potential of these electrodes was checked in the biosensing field. The procedure of simple carbon electrodes modification by antibodies was adopted to BCNW for specific antigen recognition. Surface protein D deriving from H. influenzae pathogenic bacteria was chosen as a target analyte. The electrode was first modified with the aminobenzoic acid diazonium salt by electrografting (electrochemical reduction), next anti-protein D antibodies were linked via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) chemistry, and free sites were blocked by BSA. Cyclic voltammetry measurements confirmed the proper electrode modification. Electrochemical impedance spectroscopy records indicated protein detection. The sensor was proven to detect protein D in femtograms. This work was supported by the National Centre for Research and Development (NCBR) TECHMATSTRATEG 1/347324/12/NCBR/ 2017.

Keywords: anti-protein D antibodies, boron-doped carbon nanowall, impedance spectroscopy, Haemophilus influenzae.

Procedia PDF Downloads 155
883 Direct-Displacement Based Design for Buildings with Non-Linear Viscous Dampers

Authors: Kelly F. Delgado-De Agrela, Sonia E. Ruiz, Marco A. Santos-Santiago

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An approach is proposed for the design of regular buildings equipped with non-linear viscous dissipating devices. The approach is based on a direct-displacement seismic design method which satisfies seismic performance objectives. The global system involved is formed by structural regular moment frames capable of supporting gravity and lateral loads with elastic response behavior plus a set of non-linear viscous dissipating devices which reduce the structural seismic response. The dampers are characterized by two design parameters: (1) a positive real exponent α which represents the non-linearity of the damper, and (2) the damping coefficient C of the device, whose constitutive force-velocity law is given by F=Cvᵃ, where v is the velocity between the ends of the damper. The procedure is carried out using a substitute structure. Two limits states are verified: serviceability and near collapse. The reduction of the spectral ordinates by the additional damping assumed in the design process and introduced to the structure by the viscous non-linear dampers is performed according to a damping reduction factor. For the design of the non-linear damper system, the real velocity is considered instead of the pseudo-velocity. The proposed design methodology is applied to an 8-story steel moment frame building equipped with non-linear viscous dampers, located in intermediate soil zone of Mexico City, with a dominant period Tₛ = 1s. In order to validate the approach, nonlinear static analyses and nonlinear time history analyses are performed.

Keywords: based design, direct-displacement based design, non-linear viscous dampers, performance design

Procedia PDF Downloads 182
882 Synthesis and Study of Properties of Polyaniline/Nickel Sulphide Nanocomposites

Authors: Okpaneje Onyinye Theresa, Ugwu Laeticia Udodiri, Okereke Ngozi Agatha, Okoli Nonso Livinus

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This work is on the synthesis and study of the optical characterization of polyaniline/nickel sulphide nanocomposite. Polyaniline (PANI) and nickel sulphide (NiS) nanoparticles were synthesized by oxidative chemical polymerization and sol-gel method. The polyaniline nickel sulphide nanocomposites with various concentrations of NiS were synthesized by in-situ polymerization of aniline monomer. In each case, the nickel sulphide nanoparticles were uniformly dispersed in the aniline hydrochloride before the initiation of oxidative chemical polymerization using ammonium persulphate. The samples formed were subjected to optical characterization using an ultraviolet (UV)-visible light (VIS) spectrophotometer (model: 756S UV – VIS). Optical analysis of the synthesized nanoparticles and nanocomposites showed absorption of radiation within VIS regions. The Tauc model was used to obtain the optical band gap. Energy band gap values of PANI and NiS were found to be 2.50 eV and 1.95 eV, respectively. PANI/NiSnanocomposites has an energy band gap that decreased from 2.25 eV to 1.90 eV as the amount of NiS increased (from 0.5g to 2.0g). These optical results showed that these nanocomposites are potential materials to be considered in solar cells and optoelectronics devices. The structural analysis confirmed the formation of polyaniline and hexagonal nickel sulphide with an average crystallite size of 25.521 nm, while average crystallite sizes of PANI/NiSnanocomposites ranged from 19.458 nm to 25.108 nm. Average particle sizes obtained from the SEM images ranged from 23.24 nm to 51.88 nm. Compositional results confirmed the presence of desired elements that made up the nanoparticles and nanocomposites.

Keywords: polyaniline, nickel sulphide, polyaniline-nickel sulphide nanocomposite, optical characterization, structural analysis, morphological properties, compositional properties

Procedia PDF Downloads 92
881 The Study of X- Bracing on Limit State Behaviour of Buckling Restrained Brace (BRB) in Steel Frames Using Pushover Analysis

Authors: Peyman Shadman Heidari, Hamid Bastani, Pouya Shadman Heidari

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Nowadays, using energy dampers in structures is highly considered for the dissipation and absorption of earthquake energy. The main advantage of using energy damper is absorbing the earthquake energy in some sections apart from the structure frame. Among different types of dampers, hysteresis dampers are of special place because of low cost, high reliability and the lack of mechanical parts. In this paper, a special kind of hysteresis damper is considered under the name of buckling brace, which is provided with the aim of the study and investigation of cross braces in boundary behaviour of steel frames using nonlinear static analysis. In this paper, ninety three models of steel frames with cross braces of buckling type are processed with different bays and heights and their plasticity index, behaviour coefficient, distribution type and the number of plastic hinges formed were calculated. Finally, the mean behaviour coefficient was compared with standard behaviour coefficient of 2800 and the suitable mode of braces placing in improving nonlinear behaviour and suitable distribution of plastic hinges were presented. In addition, it was determined that for some placing mode of braces the behaviour coefficient will increase to 15 times of recommended 2800 standard coefficient and in some placing modes, the braced bays will show considerable difference with suggested 2800 standard behaviour coefficient relative to each other.

Keywords: buckling restrained brace, plasticity index, behaviour coefficient, resistance coefficient, plastic joints

Procedia PDF Downloads 496
880 The Role of the Urban Renewal Projects on the Reshaping of the Cities in Izmir, Turkey

Authors: Sibel Ecemis Kilic, Neslihan Karatas

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The concept of urban renewal came up with interventions to the urban areas which have social and economic problems aimed at gaining the city. In Turkey after 2000, urban renewal has become a frequent topic on the agenda; regulations have been developed in this regard. Urban renewal project would be a focal point for the formation of the city in the near future. The future of the city is directly related to how to achieve these applications. Urban renewal policies will be decisive in the positive or negative development of the potential of the existing renewal process. Urban renewal is seen as a refreshing new planned action for reshaping unplanned and uncontrolled growth of big cities/metropolitan areas. In this context, Izmir is one of the largest metropolitan areas which came on the agenda of urban renewal application in the recent period. Izmir, which is the third largest city of Turkey, is an important trade and port city. The city, located west of Turkey, is a gate opening to Europe. In particular, continued its development rapidly after the Republican Period, it has become an important big city today. Assessment of the current situation shows that the majority of existing residential areas was formed with squatters and unplanned settlements in Izmir city center. Therefore, an important part of these areas have significant problems in terms of the quality of life, safety, and environmental quality. Legal residential areas which have had developed before 2000 is seen inadequate security in terms of an earthquake. In this study, the central policies in Turkey and local policies in İzmir about urban renewal will be considered. In addition, urban renewal projects that are being implemented or applied in Izmir were discussed and suggestions will be developed in accordance with this policy.

Keywords: urban transformation, Izmir, urban planning, urban renewal

Procedia PDF Downloads 464