Search results for: power line communications
2453 In-situ Oxygen Enrichment for Underground Coal Gasification
Authors: Adesola O. Orimoloye, Edward Gobina
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Membrane separation technology is still considered as an emerging technology in the mining sector and does not yet have the widespread acceptance that it has in other industrial sectors. Underground Coal Gasification (UCG), wherein coal is converted to gas in-situ, is a safer alternative to mining method that retains all pollutants underground making the process environmentally friendly. In-situ combustion of coal for power generation allows access to more of the physical global coal resource than would be included in current economically recoverable reserve estimates. Where mining is no longer taking place, for economic or geological reasons, controlled gasification permits exploitation of the deposit (again a reaction of coal to form a synthesis gas) of coal seams in situ. The oxygen supply stage is one of the most expensive parts of any gasification project but the use of membranes is a potentially attractive approach for producing oxygen-enriched air. In this study, a variety of cost-effective membrane materials that gives an optimal amount of oxygen concentrations in the range of interest was designed and tested at diverse operating conditions. Oxygen-enriched atmosphere improves the combustion temperature but a decline is observed if oxygen concentration exceeds optimum. Experimental result also reveals the preparatory method, apparatus and performance of the fabricated membrane.Keywords: membranes, oxygen-enrichment, gasification, coal
Procedia PDF Downloads 4602452 Hardware Implementation of Local Binary Pattern Based Two-Bit Transform Motion Estimation
Authors: Seda Yavuz, Anıl Çelebi, Aysun Taşyapı Çelebi, Oğuzhan Urhan
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Nowadays, demand for using real-time video transmission capable devices is ever-increasing. So, high resolution videos have made efficient video compression techniques an essential component for capturing and transmitting video data. Motion estimation has a critical role in encoding raw video. Hence, various motion estimation methods are introduced to efficiently compress the video. Low bit‑depth representation based motion estimation methods facilitate computation of matching criteria and thus, provide small hardware footprint. In this paper, a hardware implementation of a two-bit transformation based low-complexity motion estimation method using local binary pattern approach is proposed. Image frames are represented in two-bit depth instead of full-depth by making use of the local binary pattern as a binarization approach and the binarization part of the hardware architecture is explained in detail. Experimental results demonstrate the difference between the proposed hardware architecture and the architectures of well-known low-complexity motion estimation methods in terms of important aspects such as resource utilization, energy and power consumption.Keywords: binarization, hardware architecture, local binary pattern, motion estimation, two-bit transform
Procedia PDF Downloads 3112451 Comics as an Intermediary for Media Literacy Education
Authors: Ryan C. Zlomek
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The value of using comics in the literacy classroom has been explored since the 1930s. At that point in time researchers had begun to implement comics into daily lesson plans and, in some instances, had started the development process for comics-supported curriculum. In the mid-1950s, this type of research was cut short due to the work of psychiatrist Frederic Wertham whose research seemingly discovered a correlation between comic readership and juvenile delinquency. Since Wertham’s allegations the comics medium has had a hard time finding its way back to education. Now, over fifty years later, the definition of literacy is in mid-transition as the world has become more visually-oriented and students require the ability to interpret images as often as words. Through this transition, comics has found a place in the field of literacy education research as the shift focuses from traditional print to multimodal and media literacies. Comics are now believed to be an effective resource in bridging the gap between these different types of literacies. This paper seeks to better understand what students learn from the process of reading comics and how those skills line up with the core principles of media literacy education in the United States. In the first section, comics are defined to determine the exact medium that is being examined. The different conventions that the medium utilizes are also discussed. In the second section, the comics reading process is explored through a dissection of the ways a reader interacts with the page, panel, gutter, and different comic conventions found within a traditional graphic narrative. The concepts of intersubjective acts and visualization are attributed to the comics reading process as readers draw in real world knowledge to decode meaning. In the next section, the learning processes that comics encourage are explored parallel to the core principles of media literacy education. Each principle is explained and the extent to which comics can act as an intermediary for this type of education is theorized. In the final section, the author examines comics use in his computer science and technology classroom. He lays out different theories he utilizes from Scott McCloud’s text Understanding Comics and how he uses them to break down media literacy strategies with his students. The article concludes with examples of how comics has positively impacted classrooms around the United States. It is stated that integrating comics into the classroom will not solve all issues related to literacy education but, rather, that comics can be a powerful multimodal resource for educators looking for new mediums to explore with their students.Keywords: comics, graphics novels, mass communication, media literacy, metacognition
Procedia PDF Downloads 2982450 Physical Properties and Elastic Studies of Fluoroaluminate Glasses Based on Alkali
Authors: C. Benhamideche
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Fluoroaluminate glasses have been reported as the earliest heavy metal fluoride glasses. By comparison with flurozirconate glasses, they offer a set of similar optical features, but also some differences in their elastic and chemical properties. In practice they have been less developed because their stability against devitrification is smaller than that of the most stable fluoroziconates. The purpose of this study was to investigate glass formation in systems AlF3-YF3-PbF2-MgF2-MF2 (M= Li, Na, K). Synthesis was implemented at room atmosphere using the ammonium fluoride processing. After fining, the liquid was into a preheated brass mold, then annealed below the glass transition temperature for several hours. The samples were polished for optical measurements. Glass formation has been investigated in a systematic way, using pseudo ternary systems in order to allow parameters to vary at the same time. We have chosen the most stable glass compositions for the determination of the physical properties. These properties including characteristic temperatures, density and proprieties elastic. Glass stability increases in multicomponent glasses. Bulk samples have been prepared for physical characterization. These glasses have a potential interest for passive optical fibers because they are less sensitive to water attack than ZBLAN glass, mechanically stronger. It is expected they could have a larger damage threshold for laser power transmission.Keywords: fluoride glass, aluminium fluoride, thermal properties, density, proprieties elastic
Procedia PDF Downloads 2412449 Control-Oriented Enhanced Zero-Dimensional Two-Zone Combustion Modelling of Internal Combustion Engines
Authors: Razieh Arian, Hadi Adibi-Asl
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This paper investigates an efficient combustion modeling for cycle simulation of internal combustion engine (ICE) studies. The term “efficient model” means that the models must generate desired simulation results while having fast simulation time. In other words, the efficient model is defined based on the application of the model. The objective of this study is to develop math-based models for control applications or shortly control-oriented models. This study compares different modeling approaches used to model the ICEs such as mean-value models, zero dimensional, quasi-dimensional, and multi-dimensional models for control applications. Mean-value models have been widely used for model-based control applications, but recently by developing advanced simulation tools (e.g. Maple/MapleSim) the higher order models (more complex) could be considered as control-oriented models. This paper presents the enhanced zero-dimensional cycle-by-cycle modeling and simulation of a spark ignition engine with a two-zone combustion model. The simulation results are cross-validated against the simulation results from GT-Power package and show a good agreement in terms of trends and values.Keywords: Two-zone combustion, control-oriented model, wiebe function, internal combustion engine
Procedia PDF Downloads 3412448 A Comprehensive Safety Analysis for a Pressurized Water Reactor Fueled with Mixed-Oxide Fuel as an Accident Tolerant Fuel
Authors: Mohamed Y. M. Mohsen
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The viability of utilising mixed-oxide fuel (MOX) ((U₀.₉, rgPu₀.₁) O₂) as an accident-tolerant fuel (ATF) has been thoroughly investigated. MOX fuel provides the best example of a nuclear waste recycling process. The MCNPX 2.7 code was used to determine the main neutronic features, especially the radial power distribution, to identify the hot channel on which the thermal-hydraulic (TH) study was performed. Based on the computational fluid dynamics technique, the simulation of the rod-centered thermal-hydraulic subchannel model was implemented using COMSOL Multiphysics. TH analysis was utilised to determine the axially and radially distributed temperatures of the fuel and cladding materials, as well as the departure from the nucleate boiling ratio (DNBR) along the coolant channel. COMSOL Multiphysics can simulate reality by coupling multiphysics, such as coupling between heat transfer and solid mechanics. The main solid structure parameters, such as the von Mises stress, volumetric strain, and displacement, were simulated using this coupling. When the neutronic, TH, and solid structure performances of UO₂ and ((U₀.₉, rgPu₀.₁) O₂) were compared, the results showed considerable improvement and an increase in safety margins with the use of ((U₀.₉, rgPu₀.₁) O₂).Keywords: mixed-oxide, MCNPX, neutronic analysis, COMSOL-multiphysics, thermal-hydraulic, solid structure
Procedia PDF Downloads 1062447 Criminal Attitude vs Transparency in the Arab World
Authors: Keroles Akram Saed Ghatas
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The political violence that characterized 1992 continued into 1993, creating a major security crisis for President Hosni Mubarak's government as the death toll and human rights abuses soared. Increasingly sensitive to criticism of 's human rights activities, the government established human rights departments in key ministries, beginning with the Foreign Office in February. Similar offices have been set up in the Justice and Agriculture Ministries, and plans to set up an office in the Home Office have been announced. It turned out that the main task of the law unit was to overturn the conclusions of international human rights organizations.President Mubarak was elected in a national referendum on October 4 for a third six-year term after being appointed on July 21 by the People's Assembly, an elected parliament overwhelmingly dominated by the in-power National Democratic Party will Mr. Mubarak ran unhindered. The Interior Ministry announced that nearly 16 million people cast their votes (84% of eligible voters), of which 96.28%. voted for presidential re-election.In 1993, armed Islamic extremists escalated their attacks on Christian citizens, government officials, police officers and senior security officials, resulting in casualties among the intended victims and bystanders. Sporadic attacks on buses, boats and tourist attractions also occurred throughout the year. From March 1992 to October 28, 1993, a total of 222 people lost their lives in the riots: 36 Coptic Christians and 38 other citizens; If one is a foreigner; sixty-six members of the Security Forces; and seventy-six known or suspected activists who were killed while resisting arrest. The latter was killed in airstrikes and firefights with security forces and at the site of planned attacks. On March 9-10, a series of airstrikes in Cairo, Giza, Qalyubiya province north of the capital and Aswan killed fifteen suspected militants and five members of the security forces.One of the airstrikes in Giza, part of Greater Cairo, killed the wife and son of Khalifa Mahmoud Ramadan, a suspected militant who was himself killed. The government agency Middle East News Agency reported on March 10 that the raids were part of a "broad confrontational plan aimed at ofterrorist elements"The state of emergency declared in October 1981 after the assassination of President Anwar el-Sadat was still in force in Egypt. The law, previously in effect continuously from June 1967 to May 1980, continued to grant the executive branch unique legal powers that effectively overrode the human rights guarantees of the Egyptian constitution. These provisions included wide discretionary powers in arresting and detaining individuals, as well as the ability to try civilians in military courts. The Cairo-based Independent Organization for Human Rights said so in a document sent to the United Nations in July 1993The human rights committee said the continued imposition of the state of emergency had resulted in "another constitution for the country" and "led to widespread misconduct by the security apparatus".Keywords: constitution, human rights, legal power, president, anwar, el-sadat, assassination, state of emergency, middle east, news, agency, confrontational, arresting, fugitive, leaders, terrorist, elements, armed islamic extremists.
Procedia PDF Downloads 442446 Creativity in Development of Multimedia Presentation
Authors: Mahathir Sarjan, Ramos Radzly, Noor Baiti Jamaluddin, Mohd Hafiz Zakaria, Hisham Suhadi
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Creativity is marked by the ability or power, to produce through imaginative skill and create something anew. The University is one of the great places to improve the talent in imaginative skill. Thus, it is important that for the student have a creativity to adapt the multimedia element in the development of presentation products for learning and teaching the process. The purpose of this study was to identify a creativity of the student in presentation product development. Two hundred seventeen Technical and Vocational Education (TVE) students in Universiti Tun Hussein Onn had chosen as a respondent. This study is to survey the level of creativity which is focused on knowledge, skills, presentation style and character of creative personnel. The level of creativity was measured based on the scale at low, medium and high followed by mean score level. The data collected by questionnaire then analyzed using SPSS version 20.0. The result of the study indicated that the students showed a higher of creativity (mean score in Knowledge = 4.12 and Skills= 4.02). In conjunction with the findings s implications and recommendations were suggested forward like to ensconce the research and improve with a more creativity concept in presentation product of development for learning and teaching the process.Keywords: creativity, technical, vocational education, presentation products and development for learning and teaching process
Procedia PDF Downloads 4262445 Influence of High-Resolution Satellites Attitude Parameters on Image Quality
Authors: Walid Wahballah, Taher Bazan, Fawzy Eltohamy
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One of the important functions of the satellite attitude control system is to provide the required pointing accuracy and attitude stability for optical remote sensing satellites to achieve good image quality. Although offering noise reduction and increased sensitivity, time delay and integration (TDI) charge coupled devices (CCDs) utilized in high-resolution satellites (HRS) are prone to introduce large amounts of pixel smear due to the instability of the line of sight. During on-orbit imaging, as a result of the Earth’s rotation and the satellite platform instability, the moving direction of the TDI-CCD linear array and the imaging direction of the camera become different. The speed of the image moving on the image plane (focal plane) represents the image motion velocity whereas the angle between the two directions is known as the drift angle (β). The drift angle occurs due to the rotation of the earth around its axis during satellite imaging; affecting the geometric accuracy and, consequently, causing image quality degradation. Therefore, the image motion velocity vector and the drift angle are two important factors used in the assessment of the image quality of TDI-CCD based optical remote sensing satellites. A model for estimating the image motion velocity and the drift angle in HRS is derived. The six satellite attitude control parameters represented in the derived model are the (roll angle φ, pitch angle θ, yaw angle ψ, roll angular velocity φ֗, pitch angular velocity θ֗ and yaw angular velocity ψ֗ ). The influence of these attitude parameters on the image quality is analyzed by establishing a relationship between the image motion velocity vector, drift angle and the six satellite attitude parameters. The influence of the satellite attitude parameters on the image quality is assessed by the presented model in terms of modulation transfer function (MTF) in both cross- and along-track directions. Three different cases representing the effect of pointing accuracy (φ, θ, ψ) bias are considered using four different sets of pointing accuracy typical values, while the satellite attitude stability parameters are ideal. In the same manner, the influence of satellite attitude stability (φ֗, θ֗, ψ֗) on image quality is also analysed for ideal pointing accuracy parameters. The results reveal that cross-track image quality is influenced seriously by the yaw angle bias and the roll angular velocity bias, while along-track image quality is influenced only by the pitch angular velocity bias.Keywords: high-resolution satellites, pointing accuracy, attitude stability, TDI-CCD, smear, MTF
Procedia PDF Downloads 4022444 Security as Human Value: Issue of Human Rights in Indian Sub-Continental Operations
Authors: Pratyush Vatsala, Sanjay Ahuja
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The national security and human rights are related terms as there is nothing like absolute security or absolute human right. If we are committed to security, human right is a problem and also a solution, and if we deliberate on human rights, security is a problem but also part of the solution. Ultimately, we have to maintain a balance between the two co-related terms. As more and more armed forces are being deployed by the government within the nation for maintaining peace and security, using force against its own citizen, the search for a judicious balance between intent and action needs to be emphasized. Notwithstanding that a nation state needs complete political independence; the search for security is a driving force behind unquestioned sovereignty. If security is a human value, it overlaps the value of freedom, order, and solidarity. Now, the question needs to be explored, to what extent human rights can be compromised in the name of security in Kashmir or Mizoram like places. The present study aims to explore the issue of maintaining a balance between the use of power and good governance as human rights, providing security as a human value. This paper has been prepared with an aim of strengthening the understanding of the complex and multifaceted relationship between human rights and security forces operating for conflict management and identifies some of the critical human rights issues raised in the context of security forces operations highlighting the relevant human rights principles and standards in which Security as human value be respected at all times and in particular in the context of security forces operations in India.Keywords: Kashmir, Mizoram, security, value, human right
Procedia PDF Downloads 2792443 Measuring Delay Using Software Defined Networks: Limitations, Challenges, and Suggestions for Openflow
Authors: Ahmed Alutaibi, Ganti Sudhakar
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Providing better Quality-of-Service (QoS) to end users has been a challenging problem for researchers and service providers. Building applications relying on best effort network protocols hindered the adoption of guaranteed service parameters and, ultimately, Quality of Service. The introduction of Software Defined Networking (SDN) opened the door for a new paradigm shift towards a more controlled programmable configurable behavior. Openflow has been and still is the main implementation of the SDN vision. To facilitate better QoS for applications, the network must calculate and measure certain parameters. One of those parameters is the delay between the two ends of the connection. Using the power of SDN and the knowledge of application and network behavior, SDN networks can adjust to different conditions and specifications. In this paper, we use the capabilities of SDN to implement multiple algorithms to measure delay end-to-end not only inside the SDN network. The results of applying the algorithms on an emulated environment show that we can get measurements close to the emulated delay. The results also show that depending on the algorithm, load on the network and controller can differ. In addition, the transport layer handshake algorithm performs best among the tested algorithms. Out of the results and implementation, we show the limitations of Openflow and develop suggestions to solve them.Keywords: software defined networking, quality of service, delay measurement, openflow, mininet
Procedia PDF Downloads 1652442 Bifunctional Activity and Stability of Fused Plasmodium falciparum Orotate Phosphoribosyltransferase and Orotidine 5′-Monophosphate Decarboxylase
Authors: Patsarawadee Paojinda, Waranya Imprasittichai, Sudaratana R. Krungkrai, Nirianne Marie Q. Palacpac, Toshihiro Horii, Jerapan Krungkrai
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Fusion of the last two enzymes in the pyrimidine biosynthetic pathway in the inversed order by having COOH-terminal orotate phosphoribosyltransferase (OPRT) and NH2-terminal orotidine 5'-monophosphate decarboxylase (OMPDC), as OMPDC-OPRT, are described in many organisms. Here, we produced gene fusions of Plasmodium falciparum OMPDC-OPRT and expressed the bifunctional protein in Escherichia coli. The enzyme was purified to homogeneity using affinity and anion-exchange chromatography, exhibited enzymatic activities and functioned as a dimer. The activities, although unstable, can be stabilized by its substrate and product during purification and long-term storage. Furthermore, the enzyme expressed a perfect catalytic efficiency (kcat/Km). The kcat was selectively enhanced up to 3 orders of magnitude, while the Km was not much affected and remained at low µM levels when compared to the monofunctional enzymes. The fusion of the two enzymes, creating a “super-enzyme” with perfect catalytic power and more flexibility, reflects cryptic relationship of enzymatic reactivaties and metabolic functions on molecular evolution.Keywords: bifunctional enzyme, orotate phosphoribosyltransferase, orotidine 5'-monophosphate decarboxylase, plasmodium falciparum
Procedia PDF Downloads 2852441 Using Arellano-Bover/Blundell-Bond Estimator in Dynamic Panel Data Analysis – Case of Finnish Housing Price Dynamics
Authors: Janne Engblom, Elias Oikarinen
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A panel dataset is one that follows a given sample of individuals over time, and thus provides multiple observations on each individual in the sample. Panel data models include a variety of fixed and random effects models which form a wide range of linear models. A special case of panel data models are dynamic in nature. A complication regarding a dynamic panel data model that includes the lagged dependent variable is endogeneity bias of estimates. Several approaches have been developed to account for this problem. In this paper, the panel models were estimated using the Arellano-Bover/Blundell-Bond Generalized method of moments (GMM) estimator which is an extension of the Arellano-Bond model where past values and different transformations of past values of the potentially problematic independent variable are used as instruments together with other instrumental variables. The Arellano–Bover/Blundell–Bond estimator augments Arellano–Bond by making an additional assumption that first differences of instrument variables are uncorrelated with the fixed effects. This allows the introduction of more instruments and can dramatically improve efficiency. It builds a system of two equations—the original equation and the transformed one—and is also known as system GMM. In this study, Finnish housing price dynamics were examined empirically by using the Arellano–Bover/Blundell–Bond estimation technique together with ordinary OLS. The aim of the analysis was to provide a comparison between conventional fixed-effects panel data models and dynamic panel data models. The Arellano–Bover/Blundell–Bond estimator is suitable for this analysis for a number of reasons: It is a general estimator designed for situations with 1) a linear functional relationship; 2) one left-hand-side variable that is dynamic, depending on its own past realizations; 3) independent variables that are not strictly exogenous, meaning they are correlated with past and possibly current realizations of the error; 4) fixed individual effects; and 5) heteroskedasticity and autocorrelation within individuals but not across them. Based on data of 14 Finnish cities over 1988-2012 differences of short-run housing price dynamics estimates were considerable when different models and instrumenting were used. Especially, the use of different instrumental variables caused variation of model estimates together with their statistical significance. This was particularly clear when comparing estimates of OLS with different dynamic panel data models. Estimates provided by dynamic panel data models were more in line with theory of housing price dynamics.Keywords: dynamic model, fixed effects, panel data, price dynamics
Procedia PDF Downloads 15082440 Modelling High Strain Rate Tear Open Behavior of a Bilaminate Consisting of Foam and Plastic Skin Considering Tensile Failure and Compression
Authors: Laura Pytel, Georg Baumann, Gregor Gstrein, Corina Klug
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Premium cars often coat the instrument panels with a bilaminate consisting of a soft foam and a plastic skin. The coating is torn open during the passenger airbag deployment under high strain rates. Characterizing and simulating the top coat layer is crucial for predicting the attenuation that delays the airbag deployment, effecting the design of the restrain system and to reduce the demand of simulation adjustments through expensive physical component testing.Up to now, bilaminates used within cars either have been modelled by using a two-dimensional shell formulation for the whole coating system as one which misses out the interaction of the two layers or by combining a three-dimensional formulation foam layer with a two-dimensional skin layer but omitting the foam in the significant parts like the expected tear line area and the hinge where high compression is expected. In both cases, the properties of the coating causing the attenuation are not considered. Further, at present, the availability of material information, as there are failure dependencies of the two layers, as well as the strain rate of up to 200 1/s, are insufficient. The velocity of the passenger airbag flap during an airbag shot has been measured with about 11.5 m/s during first ripping; the digital image correlation evaluation showed resulting strain rates of above 1500 1/s. This paper provides a high strain rate material characterization of a bilaminate consisting of a thin polypropylene foam and a thermoplasctic olefins (TPO) skin and the creation of validated material models. With the help of a Split Hopkinson tension bar, strain rates of 1500 1/s were within reach. The experimental data was used to calibrate and validate a more physical modelling approach of the forced ripping of the bilaminate. In the presented model, the three-dimensional foam layer is continuously tied to the two-dimensional skin layer, allowing failure in both layers at any possible position. The simulation results show a higher agreement in terms of the trajectory of the flaps and its velocity during ripping. The resulting attenuation of the airbag deployment measured by the contact force between airbag and flaps increases and serves usable data for dimensioning modules of an airbag system.Keywords: bilaminate ripping behavior, High strain rate material characterization and modelling, induced material failure, TPO and foam
Procedia PDF Downloads 692439 Harnessing the Power of Feedback to Assist Progress: A Process-Based Approach of Providing Feedback to L2 Composition Students in the United Arab Emirates
Authors: Brad Curabba
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Utilising active, process-based learning methods to improve critical thinking and writing skills of second language (L2) writers brings unique challenges. To comprehensively satisfy different learners' needs, when commenting on student work, instructors can embed multiple feedback methods so that the capstone of their abilities as writers can be achieved. This research project assesses faculty and student perceptions regarding the effectiveness of various feedback practices used in process-based writing classrooms with L2 students at the American University of Sharjah (AUS). In addition, the research explores the challenges encountered by faculty during the provision of feedback practices. The quantitative research findings are based on two concurrent electronically distributed anonymous surveys; one aimed at students who have just completed a process-based writing course, and the other at instructors who delivered these courses. The student sample is drawn from multiple sections of Academic Writing I and II, and the faculty survey was distributed among the Department of Writing Studies (DWS) faculty. Our findings strongly suggest that all methods of feedback are deemed equally important by both students and faculty. Students, in particular, find process writing and its feedback practices to have greatly contributed to their writing proficiency.Keywords: process writing, feedback, formative feedback, composition, reflection
Procedia PDF Downloads 1382438 Functionally Modified Melt-Electrospun Thermoplastic Polyurethane (TPU) Mats for Wound-Dressing Applications
Authors: Christoph Hacker, Zeynep Karahaliloglu, Gunnar Seide, Emir Baki Denkbas, Thomas Gries
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A wound dressing material is designed to facilitate wound healing and minimize scarring. An ideal wound dressing material should protect the wound from any contaminations of exogeneous microorganism. In addition, the dressing material should provide a moist environment through extraction of body fluid from the wound area. Recently, wound dressing electrospun nanofibrous membranes are produced by electrospinning from a polymer solution or a polymer melt. These materials have a great potential as dressing materials for wound healing because of superior properties such as high surface-to-volume ratio, high porosity with excellent pore interconnectivity. Melt electrospinning is an attractive tissue engineering scaffold manufacturing process which eliminated the health risk posed by organic solvents used in electrospinning process and reduced the production costs. In this study, antibacterial wound dressing materials were prepared from TPU (Elastollan 1185A) by a melt-electrospinning technique. The electrospinning parameters for an efficient melt-electrospinning process of TPU were optimized. The surface of the fibers was modified with poly(ethylene glycol) (PEG) by radio-frequency glow discharge plasma deposition method and with silver nanoparticles (nAg) to improve their wettability and antimicrobial properties. TPU melt-electrospun mats were characterized using SEM, DSC, TGA and XPS. The cell viability and proliferation on modified melt-electrospun TPU mats were evaluated using a mouse fibroblast cell line (L929). Antibacterial effects of theirs against both Staphylococcus aureus strain and Escherichia coli were investigated by disk-diffusion method. TPU was successfully processed into a porous, fibrous network of beadless fibers in the micrometer range (4.896±0.94 µm) with a voltage of 50 kV, a working distance of 6 cm, a temperature of the thermocouple and hot coil of 225–230ºC, and a flow rate of 0.1 mL/h. The antibacterial test indicated that PEG-modified nAg-loaded TPU melt-electrospun structure had excellent antibacterial effects and cell study results demonstrated that nAg-loaded TPU mats had no cytotoxic effect on the fibroblast cells. In this work, the surface of a melt-electrospun TPU mats was modified via PEG monomer and then nAg. Results showed melt-electrospun TPU mats modified with PEG and nAg have a great potential for use as an antibacterial wound dressing material and thus, requires further investigation.Keywords: melt electrospinning, nanofiber, silver nanoparticles, wound dressing
Procedia PDF Downloads 4622437 Assessment of Records Management in Registry Department of Kebbi State University of Science and Technology, Aliero Nigeria
Authors: Murtala Aminu, Salisu Adamu Aliero, Adamu Muhammed
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Records are a vital asset in ensuring that the institution is governed effectively and efficiently, and is accountable to its staff, students and the community that it serves. The major purpose of this study was to assess record management of the registry department of Kebbi state University of science and technology Aliero. To be able to achieve this objective, research questions were formulated and answers obtained, which centered on records creation, record management policy, challenges facing records management. The review of related literature revealed that there is need for records to be properly managed and in doing so there is need for good records management policy that clearly spells out the various programs required for effective records management. Survey research method was used involving questionnaire, and observation. The findings revealed that the registry department of the University still has a long way to go with respect to day-today records management. The study recommended provision for adequate, modern, safe and functional storage facilities, sufficient and regular funding, recruitment of trained personnel, on the job training for existing staff, computerization of all units records, and uninterrupted power supply to all parts of the unit as a means of ensuring proper records management.Keywords: records, management, records management policy, registry
Procedia PDF Downloads 3162436 Experimental Investigation of Compressed Natural Gas Injector for Direct Injection System
Authors: Rafal Sochaczewski, Grzegorz Baranski, Adam Majczak
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This paper presents the bench research results on a CNG injector at steady state. The quantities measured included voltage and current in a solenoid, pressure of gas behind an injector and injector’s flow rate. Accordingly, injector’s operation parameters were determined according to needle’s lift and injection pressure. The discrepancies between the theoretical (electric) and actual time of injection were defined to specify injector’s opening and closing lag times and the uniqueness of these values in successive cycles of gas injection. It has been demonstrated that needle’s lift has got a stronger impact on injector’s operating parameters than injection pressure. With increasing injection pressure, the force increases and closes an injection valve, which adversely affects uniqueness of injector’s operation. The paper also describes the concept of an injector dedicated to direct CNG injection into a combustion chamber in a dual-fuel engine. The injector’s design enables us to replace 80% of diesel fuel in a dual-fuel engine with a maximum power of 85 kW. Minimum injection pressure is 1,4 MPa then. Simultaneously, injector’s characteristics for varied needle’s lifts and injector’s nonlinear operating points were developed. Acknowledgement: This work has been financed by the Polish National Centre for Research and Development, under Grant Agreement No. PBS1/A6/4/2012.Keywords: CNG injector, diesel engine, direct injection, dual fuel
Procedia PDF Downloads 2762435 The Effect of Swirl on the Flow Distribution in Automotive Exhaust Catalysts
Authors: Piotr J. Skusiewicz, Johnathan Saul, Ijhar Rusli, Svetlana Aleksandrova, Stephen. F. Benjamin, Miroslaw Gall, Steve Pierson, Carol A. Roberts
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The application of turbocharging in automotive engines leads to swirling flow entering the catalyst. The behaviour of this type of flow within the catalyst has yet to be adequately documented. This work discusses the effect of swirling flow on the flow distribution in automotive exhaust catalysts. Compressed air supplied to a moving-block swirl generator allowed for swirling flow with variable intensities to be generated. Swirl intensities were measured at the swirl generator outlet using single-sensor hot-wire probes. The swirling flow was fed into diffusers with total angles of 10°, 30° and 180°. Downstream of the diffusers, a wash-coated diesel oxidation catalyst (DOC) of length 143.8 mm, diameter 76.2 mm and nominal cell density of 400 cpsi was fitted. Velocity profiles were measured at the outlet sleeve about 30 mm downstream of the monolith outlet using single-sensor hot-wire probes. Wall static pressure was recorded using a multi-tube manometer connected to pressure taps positioned along the diffuser walls. The results show that as swirl is increased, more of the flow is directed towards the diffuser walls. The velocity decreases around the centre-line and maximum velocities are observed close to the outer radius of the monolith for all flow rates. At the maximum swirl intensity, reversed flow was recorded near the centre of the monolith. Wall static pressure measurements in the 180° diffuser indicated no pressure recovery as the flow enters the diffuser. This is indicative of flow separation at the inlet to the diffuser. To gain insight into the flow structure, CFD simulations have been performed for the 180° diffuser for a flow rate of 63 g/s. The geometry of the model consists of the complete assembly from the upstream swirl generator to the outlet sleeve. Modelling of the flow in the monolith was achieved using the porous medium approach, where the monolith with parallel flow channels is modelled as a porous medium that resists the flow. A reasonably good agreement was achieved between the experimental and CFD results downstream of the monolith. The CFD simulations allowed visualisation of the separation zones and central toroidal recirculation zones that occur within the expansion region at certain swirl intensities which are highlighted.Keywords: catalyst, computational fluid dynamics, diffuser, hot-wire anemometry, swirling flow
Procedia PDF Downloads 3042434 Identification of a Lead Compound for Selective Inhibition of Nav1.7 to Treat Chronic Pain
Authors: Sharat Chandra, Zilong Wang, Ru-Rong Ji, Andrey Bortsov
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Chronic pain (CP) therapeutic approaches have limited efficacy. As a result, doctors are prescribing opioids for chronic pain, leading to opioid overuse, abuse, and addiction epidemic. Therefore, the development of effective and safe CP drugs remains an unmet medical need. Voltage-gated sodium (Nav) channels act as cardiovascular and neurological disorder’s molecular targets. Nav channels selective inhibitors are hard to design because there are nine closely-related isoforms (Nav1.1-1.9) that share the protein sequence segments. We are targeting the Nav1.7 found in the peripheral nervous system and engaged in the perception of pain. The objective of this project was to screen a 1.5 million compound library for identification of inhibitors for Nav1.7 with analgesic effect. In this study, we designed a protocol for identification of isoform-selective inhibitors of Nav1.7, by utilizing the prior information on isoform-selective antagonists. First, a similarity search was performed; then the identified hits were docked into a binding site on the fourth voltage-sensor domain (VSD4) of Nav1.7. We used the FTrees tool for similarity searching and library generation; the generated library was docked in the VSD4 domain binding site using FlexX and compounds were shortlisted using a FlexX score and SeeSAR hyde scoring. Finally, the top 25 compounds were tested with molecular dynamics simulation (MDS). We reduced our list to 9 compounds based on the MDS root mean square deviation plot and obtained them from a vendor for in vitro and in vivo validation. Whole-cell patch-clamp recordings in HEK-293 cells and dorsal root ganglion neurons were conducted. We used patch pipettes to record transient Na⁺ currents. One of the compounds reduced the peak sodium currents in Nav1.7-HEK-293 stable cell line in a dose-dependent manner, with IC50 values at 0.74 µM. In summary, our computer-aided analgesic discovery approach allowed us to develop pre-clinical analgesic candidate with significant reduction of time and cost.Keywords: chronic pain, voltage-gated sodium channel, isoform-selective antagonist, similarity search, virtual screening, analgesics development
Procedia PDF Downloads 1232433 Biological Activities of Gentiana brachyphylla Vill. Herba from Turkey
Authors: Hulya Tuba Kiyan, Nilgun Ozturk
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Gentiana, a member of Gentianaceae, is represented by approximately 400 species in the world and 12 species in Turkey. Flavonoids, iridoids, triterpenoids and also xanthones are the major compounds of this genus, have been previously reported to have antiinflammatory, antimicrobial, antioxidant, hepatoprotective, hypotensive, hypoglycaemic, DNA repair and immunomodulatory properties. The methanolic extract of the aerial parts of Gentiana brachyphylla Vill. from Turkey was evaluated for its biological activities and its total phenolic content in the present study. According to the antioxidant activity results, G. brachyphylla methanolic extract showed very strong anti-DNA damage antioxidant activity with an inhibition of 81.82%. It showed weak ferric-reducing power with a EC50 value of 0.65 when compared to BHT (EC50 = 0.2). Also, at 0.5 mg/ml concentration, the methanolic extract inhibited ABTS radical cation activity with an inhibition of 20.13% when compared to Trolox (79.01%). Chelating ability of G. brachyphylla was 44.71% whereas EDTA showed 78.87% chelating activity at 0.2 mg/ml. Also G. brachyphylla showed weak 27.21% AChE, 20.23% BChE, strong 67.86% MAO-A and moderate 50.06% MAO-B, weak 19.14% COX-1, 29.11% COX-2 inhibitory activities at 0.25 mg/ml. The total phenolic content of G. brachyphylla was 156.23 ± 2.73 mg gallic acid equivalent/100 g extract.Keywords: antioxidant activity, cholinesterase inhibitory activity, Gentiana brachyphylla Vill., total phenolic content
Procedia PDF Downloads 2012432 Forecasting 24-Hour Ahead Electricity Load Using Time Series Models
Authors: Ramin Vafadary, Maryam Khanbaghi
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Forecasting electricity load is important for various purposes like planning, operation, and control. Forecasts can save operating and maintenance costs, increase the reliability of power supply and delivery systems, and correct decisions for future development. This paper compares various time series methods to forecast 24 hours ahead of electricity load. The methods considered are the Holt-Winters smoothing, SARIMA Modeling, LSTM Network, Fbprophet, and Tensorflow probability. The performance of each method is evaluated by using the forecasting accuracy criteria, namely, the mean absolute error and root mean square error. The National Renewable Energy Laboratory (NREL) residential energy consumption data is used to train the models. The results of this study show that the SARIMA model is superior to the others for 24 hours ahead forecasts. Furthermore, a Bagging technique is used to make the predictions more robust. The obtained results show that by Bagging multiple time-series forecasts, we can improve the robustness of the models for 24 hours ahead of electricity load forecasting.Keywords: bagging, Fbprophet, Holt-Winters, LSTM, load forecast, SARIMA, TensorFlow probability, time series
Procedia PDF Downloads 952431 Contested Visions of Exploration in IR: Theoretical Engagements, Reflections and New Agendas on the Dynamics of Global Order
Authors: Ananya Sharma
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International Relations is a discipline of paradoxes. The State is the dominant political institution, with mainstream analysis theorizing the State, but theory remains at best a reactionary monolith. Critical Theorists have been pushing the envelope and to that extent, there has been a clear shift in the dominant discourse away from State-centrism to individuals and group-level behaviour. This paradigm shift has been accompanied with more nuanced conceptualizations of other variables at play–power, security, and trust, to name a few. Yet, the ambit of “what is discussed” remains primarily embedded in realist conceptualizations. With this background in mind, this paper will attempt to understand, juxtapose and evaluate how “order” has been conceptualized in International Relations theory. This paper is a tentative attempt to present a “state of the art” and in the process, set the stage for a deeper study to draw attention to what the author feels is a gaping lacuna in IR theory. The paper looks at how different branches of international relations theory envisage world order and the silences embedded therein. Further, by locating order and disorder inhabiting the same reality along a continuum, alternative readings of world orders are drawn from the critical theoretical traditions, in which various articulations of justice impart the key normative pillar to the world order.Keywords: global justice, international relations theory, legitimacy, world order
Procedia PDF Downloads 3462430 Thickness Dependence of AC Conductivity in Plasma Poly(Ethylene Oxide) Thin Films
Authors: S. Yakut, D. Deger, K. Ulutas, D. Bozoglu
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Plasma poly(ethylene oxide) (pPEO) thin films were deposited between Aluminum (Al) electrodes on glass substrates by plasma assisted physical vapor deposition (PAPVD). The deposition was operated inside Argon plasma under 10⁻³ Torr and the thicknesses of samples were determined as 20, 100, 250, 500 nm. The plasma was produced at 5 W by magnetron connected to RF power supply. The capacitance C and dielectric loss factor tan δ were measured by Novovontrol Alpha-A high frequency empedance analyzer at freqquency and temperature intervals of 0,1 Hz and 1MHz, 193-353K, respectively. AC conductivity was derived from these values. AC conductivity results exhibited three different conductivity regions except for 20 nm. These regions can be classified as low, mid and high frequency regions. Low frequency region is observed at around 10 Hz and 300 K while mid frequency region is observed at around 1 kHz and 300 K. The last one, high frequency region, is observed at around 1 kHz and 200 K. There are some coinciding definitions for conduction regions, because these regions shift depending on temperature. Low frequency region behaves as DC-like conductivity while mid and high frequency regions show conductivities corresponding to mechanisms such as classical hopping, tunneling, etc. which are observed for amorphous materials. Unlike other thicknesses, for 20 nm sample low frequency region can not be detected in the investigated freuency range. It is thought that this is arised because of the presence of dead layer behavior.Keywords: plasma polymers, dead layer, dielectric spectroscopy, AC conductivity
Procedia PDF Downloads 2052429 Representation of Phonemic Changes in Arabic Dialect of Yemen: Speech Disorder and Consonant Substitution
Authors: Sadeq Al Yaari, Muhammad Alkhunayn, Adham Al Yaari, Montaha Al Yaari, Ayman Al Yaari, Aayah Al Yaari, Sajedah Al Yaari, Fatehi Eissa
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Introduction: Like many dialects, the Arabic dialect of Yemen (ADY) exhibited utterance phonemic distinction- vowel deletion, lengthening, and insertion- that were investigated using speakers from different dialectal backgrounds, with particular focus on the difference typically developing and achieving speakers and those suffering linguistic problems make. Phonological variations were found to be inevitable, suggesting further investigation of consonants to see to what extent they are prone to such phonemic changes. This study investigates the patterns of consonant substitution in ADY by examining if there is a clear-cut line between normal and pathological consonants to decide which of these consonants is substituted more. Methods: A total of hundred and twenty nine Yemeni male participants (age= 6-13) were enrolled in this study. Participants were preassigned into two groups (Articulation disorders (AD) group= 42 and typically developing and achieving group (TD) = 70), each of which consists of five sub-groups in decided sociolinguistic classification. In a 45 minute-session, 180 pictures of commonly used verbs (4 pics/m.) were presented to participants who were asked to impulsively describe these verbs before their production was psychoneurolinguistically and statistically analyzed. Results: There was a pattern of consonant substitution in some dialects that participants from both groups have in common: Voiceless consonants (/t/, /ṣ/,/s/, /ḥ, /k/, /ʃ/, /f//, and /k/) in northern and eastern dialects; voiced consonants (/q/, /gh/, /Ʒ/, /g/,/ḍ/, /b/, and /d/) in southern, eastern, western and central dialects; and voiceless and voiced consonants(/t/, /f/, /Ø/, /ṣ/, /s/, /q/, /gh/, /Ʒ/, /g/,/ḍ/, and /b/) in southern dialect. Voiceless consonants (/t/, /ṣ/,/s/, /ḥ, /k/, /ʃ/, /f//, /Ø/and /k/) found to be substituted more by ADY speakers of both AD and TD groups followed by voiced consonants (/q/, /gh/, /Ʒ/, /g/,/ḍ/,/d/ /b/, and /ð/), nasals (/m/, /n/), mute (/h/), semi-vowels (/w/ and /j/) and laterals (/l/ and /r/). Unexpectedly, a short vowel (/æ/) and two long vowels (/u: and /a:/) were found to substitute consonants in ADY both by AD and TD participants. Conclusions: AD and TD participants of ADY substitute consonants in their dialectal speech. Consonant substitution processes cover not only consonants but extend to include monophthongs. The finding that speakers of ADY substitute consonants in multisyllabic words is probably due to the fact that the sociolinguistic factor plays a pivotal role in the problematic substitution of consonants in ADY speakers. Larger longitudinal studies are necessary to further investigate the effect of sociolinguistic background on phonological variations, notably sound change in the speech of Yemeni TD speakers compared to those with linguistic impairments.Keywords: consonant substitution, Arabic dialect of Yemen, phonetics, phonology, syllables, articulation disorders
Procedia PDF Downloads 432428 Effects of Foreign-language Learning on Bilinguals' Production in Both Their Languages
Authors: Natalia Kartushina
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Foreign (second) language (L2) learning is highly promoted in modern society. Students are encouraged to study abroad (SA) to achieve the most effective learning outcomes. However, L2 learning has side effects for native language (L1) production, as L1 sounds might show a drift from the L1 norms towards those of the L2, and this, even after a short period of L2 learning. L1 assimilatory drift has been attributed to a strong perceptual association between similar L1 and L2 sounds in the mind of L2 leaners; thus, a change in the production of an L2 target leads to the change in the production of the related L1 sound. However, nowadays, it is quite common that speakers acquire two languages from birth, as, for example, it is the case for many bilingual communities (e.g., Basque and Spanish in the Basque Country). Yet, it remains to be established how FL learning affects native production in individuals who have two native languages, i.e., in simultaneous or very early bilinguals. Does FL learning (here a third language, L3) affect bilinguals’ both languages or only one? What factors determine which of the bilinguals’ languages is more susceptible to change? The current study examines the effects of L3 (English) learning on the production of vowels in the two native languages of simultaneous Spanish-Basque bilingual adolescents enrolled into the Erasmus SA English program. Ten bilingual speakers read five Spanish and Basque consonant-vowel-consonant-vowel words two months before their SA and the next day after their arrival back to Spain. Each word contained the target vowel in the stressed syllable and was repeated five times. Acoustic analyses measuring vowel openness (F1) and backness (F2) were performed. Two possible outcomes were considered. First, we predicted that L3 learning would affect the production of only one language and this would be the language that would be used the most in contact with English during the SA period. This prediction stems from the results of recent studies showing that early bilinguals have separate phonological systems for each of their languages; and that late FL learner (as it is the case of our participants), who tend to use their L1 in language-mixing contexts, have more L2-accented L1 speech. The second possibility stated that L3 learning would affect both of the bilinguals’ languages in line with the studies showing that bilinguals’ L1 and L2 phonologies interact and constantly co-influence each other. The results revealed that speakers who used both languages equally often (balanced users) showed an F1 drift in both languages toward the F1 of the English vowel space. Unbalanced speakers, however, showed a drift only in the less used language. The results are discussed in light of recent studies suggesting that the amount of language use is a strong predictor of the authenticity in speech production with less language use leading to more foreign-accented speech and, eventually, to language attrition.Keywords: language-contact, multilingualism, phonetic drift, bilinguals' production
Procedia PDF Downloads 1092427 Federalism, a System of Government: Comparative Study of Australia and Canada
Authors: Rana Tajammal Rashid
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Federalism is a political system in which government power and responsibility are divided between a federal legislature and units of the state or provincial legislatures. This system provides the structure for the states having large territory and through that can manage the state affairs and administration easily. Many of the largest countries in the world are federations, like; The United States, Canada, India, Pakistan South Africa, Argentina, and Australia. Every large democratic nation has a federal system of government. This study will explore the feature and good governance of two developed countries Canada and Australia. This study will be helpful to the developing countries like Pakistan, India which have a federal form of structure to run the affairs of the state. In the federal system of Pakistan there are lot of issues and conflicts with the provinces with a comparative study of these two developed countries, i.e., Australia and Canada, our policy and decision maker political actors will understand in which way a state will successfully manage the issues related to federalism. This study will also provide the help to the students of comparative politics that how to analysis the different political system of the developed countries of the world.Keywords: federalism, features of federalism, types of federalism, history of federalism, Australian federalism, Canadian federalism, federalism developments, executives, federal and provincial autonomy legislative, judicial
Procedia PDF Downloads 2872426 Policies and Politics of Infrastructure Provisioning in Nigeria
Authors: Olufemi Adedamola Oyedele
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Infrastructure provision in Nigeria is now at its lowest ebb in spite of its being critical to the socio-economic and political development of any nation. This is partly because the policy that will ensure its adequate provisioning is missing and partly because politics is affecting its provision. Policy is the basic principles by which a government is guided. Infrastructural development is the basis for measuring the performance of governments and it is the foundation of good governance. Demand for infrastructural development is higher and resources used in its provision are limited. Ethnic-interest agitation and lobbying for infrastructure provision are common things in multi-ethnic state like Nigeria. Most infrastructures are now decayed and need repair or replacement. Government is the system that organizes, control and sensitizes the people in a society in other for all to have an acceptable level of living. Governments have the power to put in place all measures that they deem fit will make an environment conducive for living for everybody. Infrastructure development in any environment requires needs assessment, feasibility and viability studies and carrying out physical development of the project. The challenge in Nigeria is largely carrying out development where they are not needed but where the people are loyal. There are numerous abandoned projects because they were started due to politics and not because they are feasible. Policies and politics greatly affect infrastructure provisioning in Nigeria and this is the premise of this paper.Keywords: infrastructure challenges, infrastructure development, policy making, politics, project finance
Procedia PDF Downloads 2792425 Potential of Ozonation and Phytoremediation to Reduce Hydrocarbon Levels Remaining after the Pilot Scale Microbial Based Bioremediation (Land-Farming) of a Heavily Polluted Soil
Authors: Hakima Althalb
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Petroleum contamination of sandy soils is a severe environmental problem in Libya, but relatively little work has been carried out to optimize the bioremediation of such heavily contaminated soil, particularly at a pilot scale. The purpose of this research was to determine the potential for the microbial-based bioremediation of hydrocarbon-contaminated soil obtained from an oil refinery in Libya and to assess the potential of both ozonation and phytoremediation (both applied after initial bioremediation) to reduce residual hydrocarbon levels. Plots containing 500 kg soil (triplicates) (contaminated soil diluted with clean soil 50% volume) were set up, (designated as Land Treatment Units; LTUs) containing five different nutrient levels and mixtures (Urea + NPK (nitrogen; phosphor; potassium) mixtures) to obtain C:N:P ratios 100:10:1, and monitored for 90 days. Hydrocarbon levels, microbial numbers, and toxicity (EC50 using luminescent microbial based tests) were assessed. Hydrocarbon levels in non-diluted and diluted soil ranged from 20 733-22 366 mg/kg and from 16 000-17 000 mg/kg respectively. Although all the land treatment units revealed a significant hydrocarbon reduction over time, the highest reduction in hydrocarbon levels obtained was around 60%. For example, 63% hydrocarbon removal was observed using a mixture of urea and NPK with a C:N:P ratio of 100:10:1). Soil toxicity (as assessed using luminescence based toxicity assays) reduced in line with the reduction in total petroleum hydrocarbons observed. However, as relatively high residual TPH (total petroleum hydrocarbon) levels (ranging from 6033-14166mg/kg) were still present after initial bioremediation two ‘post-treatments’ (phytoremediation and ozonation) were attempted to remove residual hydrocarbons remaining. Five locally grown (agriculturally important) plant species were tested. The germination of all plants examined was strongly inhibited (80-100%) and seedlings failed to grow well in the contaminated soil, indicating that the previously bioremediated soils were still toxic to the plants. Subsequent ozonation followed by another bioremediation of soil was more successful than phytoremediation. But even the most promising successful treatment in this study (ozonation for 6 hours at 25ppm followed by bioremediation) still only removed approximately 31% of the residual hydrocarbons. Overall, this work showed that the bioremediation of such highly contaminated soils is difficult and that a combination of treatments would be required to achieve successful remediation. Even after initial dilution and bioremediation the soils remained toxic to plant growth and were therefore not suitable for phytoremediation.Keywords: bioremediation, petroleum hydrocarbons, ozone, phytoremediation
Procedia PDF Downloads 1832424 Medical Image Augmentation Using Spatial Transformations for Convolutional Neural Network
Authors: Trupti Chavan, Ramachandra Guda, Kameshwar Rao
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The lack of data is a pain problem in medical image analysis using a convolutional neural network (CNN). This work uses various spatial transformation techniques to address the medical image augmentation issue for knee detection and localization using an enhanced single shot detector (SSD) network. The spatial transforms like a negative, histogram equalization, power law, sharpening, averaging, gaussian blurring, etc. help to generate more samples, serve as pre-processing methods, and highlight the features of interest. The experimentation is done on the OpenKnee dataset which is a collection of knee images from the openly available online sources. The CNN called enhanced single shot detector (SSD) is utilized for the detection and localization of the knee joint from a given X-ray image. It is an enhanced version of the famous SSD network and is modified in such a way that it will reduce the number of prediction boxes at the output side. It consists of a classification network (VGGNET) and an auxiliary detection network. The performance is measured in mean average precision (mAP), and 99.96% mAP is achieved using the proposed enhanced SSD with spatial transformations. It is also seen that the localization boundary is comparatively more refined and closer to the ground truth in spatial augmentation and gives better detection and localization of knee joints.Keywords: data augmentation, enhanced SSD, knee detection and localization, medical image analysis, openKnee, Spatial transformations
Procedia PDF Downloads 154