Search results for: specific energy
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14955

Search results for: specific energy

5685 Analysis of the Engineering Judgement Influence on the Selection of Geotechnical Parameters Characteristic Values

Authors: K. Ivandic, F. Dodigovic, D. Stuhec, S. Strelec

Abstract:

A characteristic value of certain geotechnical parameter results from an engineering assessment. Its selection has to be based on technical principles and standards of engineering practice. It has been shown that the results of engineering assessment of different authors for the same problem and input data are significantly dispersed. A survey was conducted in which participants had to estimate the force that causes a 10 cm displacement at the top of a axially in-situ compressed pile. Fifty experts from all over the world took part in it. The lowest estimated force value was 42% and the highest was 133% of measured force resulting from a mentioned static pile load test. These extreme values result in significantly different technical solutions to the same engineering task. In case of selecting a characteristic value of a geotechnical parameter the importance of the influence of an engineering assessment can be reduced by using statistical methods. An informative annex of Eurocode 1 prescribes the method of selecting the characteristic values of material properties. This is followed by Eurocode 7 with certain specificities linked to selecting characteristic values of geotechnical parameters. The paper shows the procedure of selecting characteristic values of a geotechnical parameter by using a statistical method with different initial conditions. The aim of the paper is to quantify an engineering assessment in the example of determining a characteristic value of a specific geotechnical parameter. It is assumed that this assessment is a random variable and that its statistical features will be determined. For this purpose, a survey research was conducted among relevant experts from the field of geotechnical engineering. Conclusively, the results of the survey and the application of statistical method were compared.

Keywords: characteristic values, engineering judgement, Eurocode 7, statistical methods

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5684 Electricity Production Enhancement in a Constructed Microbial Fuel Cell MFC Using Iron Nanoparticles

Authors: Khaoula Bensaida, Osama Eljamal

Abstract:

The electrical energy generation through Microbial Fuel Cells (MFCs) using microorganisms is a renewable and sustainable approach. It creates truly an efficient technology for power production and wastewater treatment. MFC is an electrochemical device which turns wastewater into electricity. The most important part of MFC is microbes. Nano zero-valent Iron NZVI technique was successfully applied in degrading the chemical pollutants and cleaning wastewater. However, the use of NZVI for enhancing the current production is still not confirmed yet. This study aims to confirm the effect of these particles on the current generation by using MFC. A constructed microbial fuel cell, which utilizes domestic wastewater, has been considered for wastewater treatment and bio-electricity generation. The two electrodes were connected to an external resistor (200 ohms). Experiments were conducted in two steps. First, the MFC was constructed without adding NZVI particles (Control) while at a second step, nanoparticles were added with a concentration of 50mg/L. After 20 hours, the measured voltage increased to 5 and 8mV, respectively. To conclude, the use of zero-valent iron in an MFC system can increase electricity generation.

Keywords: bacterial growth, electricity generation, microbial fuel cell MFC, nano zero-valent iron NZVI.

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5683 Multi-Wavelength Q-Switched Erbium-Doped Fiber Laser with Photonic Crystal Fiber and Multi-Walled Carbon Nanotubes

Authors: Zian Cheak Tiu, Harith Ahmad, Sulaiman Wadi Harun

Abstract:

A simple multi-wavelength passively Q-switched Erbium-doped fiber laser (EDFL) is demonstrated using low cost multi-walled carbon nanotubes (MWCNTs) based saturable absorber (SA), which is prepared using polyvinyl alcohol (PVA) as a host polymer. The multi-wavelength operation is achieved based on nonlinear polarization rotation (NPR) effect by incorporating 50 m long photonic crystal fiber (PCF) in the ring cavity. The EDFL produces a stable multi-wavelength comb spectrum for more than 14 lines with a fixed spacing of 0.48 nm. The laser also demonstrates a stable pulse train with the repetition rate increases from 14.9 kHz to 25.4 kHz as the pump power increases from the threshold power of 69.0 mW to the maximum pump power of 133.8 mW. The minimum pulse width of 4.4 µs was obtained at the maximum pump power of 133.8 mW while the highest energy of 0.74 nJ was obtained at pump power of 69.0 mW.

Keywords: multi-wavelength Q-switched, multi-walled carbon nanotube, photonic crystal fiber

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5682 A Prospective Evaluation of Thermal Radiation Effects on Magneto-Hydrodynamic Transport of a Nanofluid Traversing a Spongy Medium

Authors: Azad Hussain, Shoaib Ali, M. Y. Malik, Saba Nazir, Sarmad Jamal

Abstract:

This article reports a fundamental numerical investigation to analyze the impact of thermal radiations on MHD flow of differential type nanofluid past a porous plate. Here, viscosity is taken as function of temperature. Energy equation is deliberated in the existence of viscous dissipation. The mathematical terminologies of nano concentration, velocity and temperature are first cast into dimensionless expressions via suitable conversions and then solved by using Shooting technique to obtain the numerical solutions. Graphs has been plotted to check the convergence of constructed solutions. At the end, the influence of effective parameters on nanoparticle concentration, velocity and temperature fields are also deliberated in a comprehensive way. Moreover, the physical measures of engineering importance such as the Sherwood number, Skin friction and Nusselt number are also calculated. It is perceived that the thermal radiation enhances the temperature for both Vogel's and Reynolds' models but the normal stress parameter causes a reduction in temperature profile.

Keywords: MHD flow, differential type nanofluid, Porous medium, variable viscosity, thermal radiation

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5681 A Flute Tracking System for Monitoring the Wear of Cutting Tools in Milling Operations

Authors: Hatim Laalej, Salvador Sumohano-Verdeja, Thomas McLeay

Abstract:

Monitoring of tool wear in milling operations is essential for achieving the desired dimensional accuracy and surface finish of a machined workpiece. Although there are numerous statistical models and artificial intelligence techniques available for monitoring the wear of cutting tools, these techniques cannot pin point which cutting edge of the tool, or which insert in the case of indexable tooling, is worn or broken. Currently, the task of monitoring the wear on the tool cutting edges is carried out by the operator who performs a manual inspection, causing undesirable stoppages of machine tools and consequently resulting in costs incurred from lost productivity. The present study is concerned with the development of a flute tracking system to segment signals related to each physical flute of a cutter with three flutes used in an end milling operation. The purpose of the system is to monitor the cutting condition for individual flutes separately in order to determine their progressive wear rates and to predict imminent tool failure. The results of this study clearly show that signals associated with each flute can be effectively segmented using the proposed flute tracking system. Furthermore, the results illustrate that by segmenting the sensor signal by flutes it is possible to investigate the wear in each physical cutting edge of the cutting tool. These findings are significant in that they facilitate the online condition monitoring of a cutting tool for each specific flute without the need for operators/engineers to perform manual inspections of the tool.

Keywords: machining, milling operation, tool condition monitoring, tool wear prediction

Procedia PDF Downloads 291
5680 Supply Side Readiness for Universal Health Coverage: Assessing the Availability and Depth of Essential Health Package in Rural, Remote and Conflict Prone District

Authors: Veenapani Rajeev Verma

Abstract:

Context: Assessing facility readiness is paramount as it can indicate capacity of facilities to provide essential care for resilience to health challenges. In the context of decentralization, estimation of supply side readiness indices at sub national level is imperative for effective evidence based policy but remains a colossal challenge due to lack of dependable and representative data sources. Setting: District Poonch of Jammu and Kashmir was selected for this study. It is remote, rural district with unprecedented topographical barriers and is identified as high priority by government. It is also a fragile area as is bounded by Line of Control with Pakistan bearing the brunt of cease fire violations, military skirmishes and sporadic militant attacks. Hilly geographical terrain, rudimentary/absence of road network and impoverishment are quintessential to this area. Objectives: Objective of the study is to a) Evaluate the service readiness of health facilities and create a concise index subsuming plethora of discrete indicators and b) Ascertain supply side barriers in service provisioning via stakeholder’s analysis. Study also strives to expand analytical domain unravelling context and area specific intricacies associated with service delivery. Methodology: Mixed method approach was employed to triangulate quantitative analysis with qualitative nuances. Facility survey encompassing 90 Subcentres, 44 Primary health centres, 3 Community health centres and 1 District hospital was conducted to gauge general service availability and service specific availability (depth of coverage). Compendium of checklist was designed using Indian Public Health Standards (IPHS) in form of standard core questionnaire and scorecard generated for each facility. Information was collected across dimensions of amenities, equipment, medicines, laboratory and infection control protocols as proposed in WHO’s Service Availability and Readiness Assesment (SARA). Two stage polychoric principal component analysis employed to generate a parsimonious index by coalescing an array of tracer indicators. OLS regression method used to determine factors explaining composite index generated from PCA. Stakeholder analysis was conducted to discern qualitative information. Myriad of techniques like observations, key informant interviews and focus group discussions using semi structured questionnaires on both leaders and laggards were administered for critical stakeholder’s analysis. Results: General readiness score of health facilities was found to be 0.48. Results indicated poorest readiness for subcentres and PHC’s (first point of contact) with composite score of 0.47 and 0.41 respectively. For primary care facilities; principal component was characterized by basic newborn care as well as preparedness for delivery. Results revealed availability of equipment and surgical preparedness having lowest score (0.46 and 0.47) for facilities providing secondary care. Presence of contractual staff, more than 1 hr walk to facility, facilities in zone A (most vulnerable) to cross border shelling and facilities inaccessible due to snowfall and thick jungles was negatively associated with readiness index. Nonchalant staff attitude, unavailability of staff quarters, leakages and constraint in supply chain of drugs and consumables were other impediments identified. Conclusions/Policy Implications: It is pertinent to first strengthen primary care facilities in this setting. Complex dimensions such as geographic barriers, user and provider behavior is not under precinct of this methodology.

Keywords: effective coverage, principal component analysis, readiness index, universal health coverage

Procedia PDF Downloads 99
5679 Development and Characterization of a Bio-Sourced Composite Material Based on Phase Change Material and Hemp Shives

Authors: Hachmi Toifane, Pierre Tittelein, Anh Dung Tran Le, Laurent Zalewsi

Abstract:

This study introduces a composite material composed of bio-sourced phase-change material (PCM) of plant origin combined with hemp shives, developed in response to environmental challenges in the construction sector. The state of the art emphasizes the low thermal storage capacity of bio-based materials and highlights increasing need for developing sustainable materials that offer optimal thermal, mechanical, and hydric performances. The combining of PCM's thermal properties and hygric properties of hemp shives results in a material that combines lightness, strength, and hygrothermal regulation. Various formulations are being assessed and compared to conventional hemp concrete. Thermal characterization includes the measurements of thermal conductivity and numerical simulations to evaluate the thermal storage capacity. The results indicate that the addition of PCM significantly enhances the material's thermal storage capacity, positioning this one as a promising, eco-friendly solution for sustainable construction and for improving the energy efficiency of buildings.

Keywords: hemp composite, bio-sourced phase change material, thermal storage, hemp shives

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5678 Calibrations and Effect of Different Operating Conditions on the Performance of a Fluid Power Control System with Servo Solenoid Valve

Authors: Tahany W. Sadak, Fouly, A. Anwer, M. Rizk

Abstract:

The current investigation presents a study on the hydraulic performance of an electro-hydraulic servo solenoid valve controlled linear piston used in hydraulic systems. Advanced methods have been used to measure and record laboratory experiments, to ensure accurate analysis and evaluation. Experiments have been conducted under different values of temperature (28, 40 and 50 °C), supply pressure (10, 20, 30, 40 and 50 bar), system stiffness (32 N/mm), and load (0.0 & 5560 N). It is concluded that increasing temperature of hydraulic oil increases the quantity of flow rate, so it achieves an increase of the quantity of flow by 5.75 % up to 48.8 % depending on operating conditions. The values of pressure decay at low temperature are less than the values at high temperature. The frequency increases with the increase of the temperature. When we connect the springs to the system, it decreases system frequency. These results are very useful in the process of packing and manufacturing of fluid products, where the properties are not affected by 50 °C, so energy and time are saved.

Keywords: electro-hydraulic servo valve, fluid power control system, system stiffness, static and dynamic performance

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5677 The Information-Seeking Behaviour of Kuwaiti Judges (KJs)

Authors: Essam Mansour

Abstract:

The key purpose of this study is to show information-seeking behaviour of Kuwaiti Judges (KJs). Being one of the few studies about the information needs and information-seeking behaviour conducted in Arab and developing countries, this study is a pioneer one among many studies conducted in information seeking, especially with this significant group of information users. The authors tried to investigate this seeking behavior in terms of KJs' thoughts, perceptions, motivations, techniques, preferences, tools and barriers met when seeking information. The authors employed a questionnaire, with a response rate 77.2 percent. This study showed that most of KJs were likely to be older, educated and with a work experience ranged from new to old experience. There is a statistically reliable significant difference between KJs' demographic characteristics and some sources of information, such as books, encyclopedias, references and mass media. KJs were using information moderately to make a decision, to be in line with current events, to collect statistics and to make a specific/general research. The office and home were the most frequent location KJs were accessing information from. KJs' efficiency level of the English language is described to be moderately good, and a little number of them confirmed that their efficiency level of French was not bad. The assistance provided by colleagues, followed by consultants, translators, sectaries and librarians were found to be most strong types of assistance needed when seeking information. Mobile apps, followed by PCs, information networks (the Internet) and information databases were the highest technology tool used by KJs. Printed materials, followed by non-printed and audiovisual materials were the most preferred information formats KJs use. The use of languages, the recency of information and the place of information, the deficit role of the library to deliver information were at least significant barriers to KJs when seeking information.

Keywords: information users, information-seeking behaviour, information needs, judges, Kuwait

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5676 Surface Modification of Titanium Alloy with Laser Treatment

Authors: Nassier A. Nassir, Robert Birch, D. Rico Sierra, S. P. Edwardson, G. Dearden, Zhongwei Guan

Abstract:

The effect of laser surface treatment parameters on the residual strength of titanium alloy has been investigated. The influence of the laser surface treatment on the bonding strength between the titanium and poly-ether-ketone-ketone (PEKK) surfaces was also evaluated and compared to those offered by titanium foils without surface treatment to optimize the laser parameters. Material characterization using an optical microscope was carried out to study the microstructure and to measure the mean roughness value of the titanium surface. The results showed that the surface roughness shows a significant dependency on the laser power parameters in which surface roughness increases with the laser power increment. Moreover, the results of the tensile tests have shown that there is no significant dropping in tensile strength for the treated samples comparing to the virgin ones. In order to optimize the laser parameter as well as the corresponding surface roughness, single-lap shear tests were conducted on pairs of the laser treated titanium stripes. The results showed that the bonding shear strength between titanium alloy and PEKK film increased with the surface roughness increment to a specific limit. After this point, it is interesting to note that there was no significant effect for the laser parameter on the bonding strength. This evidence suggests that it is not necessary to use very high power of laser to treat titanium surface to achieve a good bonding strength between titanium alloy and the PEKK film.

Keywords: bonding strength, laser surface treatment, PEKK, poly-ether-ketone-ketone, titanium alloy

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5675 The impact of Climate Change and Land use/land Cover Change (LUCC) on Carbon Storage in Arid and Semi-Arid Regions of China

Authors: Xia Fang

Abstract:

Arid and semiarid areas of China (ASAC) have experienced significant land-use/cover changes (LUCC), along with intensified climate change. However, LUCC and climate changes and their individual and interactive effects on carbon stocks have not yet been fully understood in the ASAC. This study analyses the carbon stocks in the ASAC during 1980 - 2020 using the specific arid ecosystem model (AEM), and investigates the effects of LUCC and climate change on carbon stock trends. The results indicate that in the past 41 years, the ASAC carbon pool experienced an overall growth trend, with an increase of 182.03 g C/m2. Climatic factors (+291.99 g C/m2), especially the increase in precipitation, were the main drivers of the carbon pool increase. LUCC decreased the carbon pool (-112.27 g C/m2), mainly due to the decrease in grassland area (-2.77%). The climate-induced carbon sinks were distributed in northern Xinjiang, on the Ordos Plateau, and in Northeast China, while the LUCC-induced carbon sinks mainly occurred on the Ordos Plateau and the North China Plain, resulting in a net decrease in carbon sequestration in these regions according to carbon pool measurements. The study revealed that the combination of climate variability, LUCC, and increasing atmospheric CO2 concentration resulted in an increase of approximately 182.03 g C/m2, which was mainly distributed in eastern Inner Mongolia and the western Qinghai-Tibet Plateau. Our findings are essential for improving theoretical guidance to protect the ecological environment, rationally plan land use, and understand the sustainable development of arid and semiarid zones.

Keywords: AEM, climate change, LUCC, carbon stocks

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5674 Comparison of the Effects of Rod Types of Rigid Fixation Devices on the Loads in the Lumbar Spine: A Finite Element Analysis

Authors: Bokku Kang, Changsoo Chon, Han Sung Kim

Abstract:

We developed new design of rod of pedicle screw system that is beneficial in maintaining the spacing between the vertebrae and assessed the performance of the posterior fixation screw systems by numerical analysis according to the range of motion (flexion, extension, lateral bending, and axial rotation) of the vertebral column after inserting the pedicle screws. The simulation results showed that the conventional rod was the most low equivalent stress value among implant units in the case of flexion, extension and lateral bending of the vertebrae. In all cases except the torsional rotation, the results showed that the stress level of the single and double rounded rod exceeded about 30% to 70% compare to the conventional rod. Therefore, this product is not suitable for actual application in the field yet and it seems that product design optimization is necessary. Acknowledgement: This research was supported by the Ministry of Trade, Industry & Energy (MOTIE), Korea Institute for Advancement of Technology (KIAT) through the Encouragement Program for The Industries of Economic Cooperation Region.

Keywords: lumber spine, internal fixation device, finite element method, biomechanics

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5673 Influence of Magnetic Bio-Stimulation Effects on Pre-Sown Hybrid Sunflower Seeds Germination, Growth, and on the Percentage of Antioxidant Activities

Authors: Nighat Zia-ud-Den, Shazia Anwer Bukhari

Abstract:

In the present study, sunflower seeds were exposed to magnetic bio-stimulation at different milli Tesla, and their effects were studied. The present study addressed to establish the effectiveness of magnetic bio-stimulation on seed germination, growth, and other dynamics of crop growth. The changes in physiological characters, i.e. the growth parameters of seedlings (biomass, root and shoot length, fresh and dry weight of root shoot leaf and fruit, leaf area, the height of plants, number of leaves, and number of fruits per plant) and antioxidant activities were measured. The parameters related to germination and growth were measured under controlled conditions while they changed significantly compared with that of the control. These changes suggested that magnetic seed stimulator enhanced the inner energy of seeds, which contributed to the acceleration of the growth and development of seedlings. Moreover, pretreatment with a magnetic field was found to be a positive impact on sunflower seeds germination, growth, and other biochemical parameters.

Keywords: sunflower seeds, physical priming method, biochemical parameters, antioxidant activities

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5672 Ranking of Provinces in Iran for Capital Formation in Spatial Planning with Numerical Taxonomy Technique (An Improvement) Case Study: Agriculture Sector

Authors: Farhad Nouparast

Abstract:

For more production we need more capital formation. Capital formation in each country should be based on comparative advantages in different economic sectors due to the different production possibility curves. In regional planning, recognizing the relative advantages and consequently investing in more production requires identifying areas with the necessary capabilities and location of each region compared to other regions. In this article, ranking of Iran's provinces is done according to the specific and given variables as the best investment position in agricultural activity. So we can provide the necessary background for investment analysis in different regions of the country to formulate national and regional planning and execute investment projects. It is used factor analysis technique and numerical taxonomy analysis to do this in thisarticle. At first, the provinces are homogenized and graded according to the variables using cross-sectional data obtained from the agricultural census and population and housing census of Iran as data matrix. The results show that which provinces have the most potential for capital formation in agronomy sub-sector. Taxonomy classifies organisms based on similar genetic traits in biology and botany. Numerical taxonomy using quantitative methods controls large amounts of information and get the number of samples and categories and take them based on inherent characteristics and differences indirectly accommodates. Numerical taxonomy is related to multivariate statistics.

Keywords: Capital Formation, Factor Analysis, Multivariate statistics, Numerical Taxonomy Analysis, Production, Ranking, Spatial Planning

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5671 Making Creative Ethnography through Droned Mode of Engagements

Authors: Elin Linder

Abstract:

Ethnographic endeavors feature a long history of creative modes of engagements, and anthropology an equally long critique of its disciplinary attention to worded representations of beyond worded experiences. Curious and critical as our research comes about, takes place, unfolds, and develops, processes of documenting, exploring, experiencing, and producing knowledge commonly evolve as intrinsic parts of our situated wishes to make sense of the worlds we study. We may imagine to do one thing and to use a specific mode of fieldnoting, only to end up doing something else, such as to capture dynamics and dimensions otherwise not attentively engaged or even lost. This paper builds on such an experience, and it acts window to open the conversation for doing and representing ethnographic work as creatively as it was undertaken. Expressively and actively undertaken by means of sensuous scholarship, fieldworking in the world of olivicoltura in Apulia intriguingly advanced into resourcefully embodied research using a drone. While the drone first and foremost allowed perspectives that one as a human is largely and physically incapable of exploring, it rapidly emerged into a mode of engagement that probed critical question how one comes to learn how to see that which one watches, listen to that which one hears, smell that which one scents, feel that which one touch, and gather that which one experience. This paper develops how the drone incorporated a transition of a particularly situated ethnographic sense of attention, all while visualizing how imaginative conceptualizations enable unexpected modes of multimodal knowing in much multisensorial worlds of being.

Keywords: drone, multimodality, sensuous scholarship, critical creativity, ethnographic practice

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5670 Study of Some Factors Effecting on Productivity of Solar Distillers

Authors: Keshek M.H, Mohamed M.A, El-Shafey M.A

Abstract:

The aim of this research was increasing the productivity of solar distillation. In order to reach this aim, a solar distiller was created with three glass sides sloping 30o at the horizontal level, and the experiments were carried out on the solar distillation unit during the period from 24th August, 2016 till 24th May, 2017 at the Agricultural Engineering and Bio Systems Department, Faculty of Agriculture, Menoufia University. Three gap lengths were used between the water level and the inner glass cover, those were 3, 6, and 9 cm. As the result of change the gap length between the water level and the inner glass cover the total volume of basins were changed from 15.5, 13, and 11 L, respectively. The total basin volume was divided to three sections, to investigate the effect of water volume. The three water volumes were 100%, 75%, and 50%. Every section was supplied with one, two, or three heaters. The one heater power was 15 W. The results showed that, by increasing the distance between the basins edge and the inner edge of the glass cover, an increase occurs in the percentage of temperature difference with maximum value was 52% at distance 9 cm from each edge, an increase occurs in the productivity with maximum productivity was 3.3 L/m2 at distance 9 cm from each edge and an increase occurs in the efficiency with maximum efficiency was 70% at distance 9 cm from each edge.

Keywords: distillation, solar energy, still productivity, efficiency

Procedia PDF Downloads 92
5669 Niche Authorities and Social Activism: Interrogating the Activities of Selected Bloggers in Ghana

Authors: Akosua Asantewaa Anane

Abstract:

Social media and its networking sites have become beneficial to society. With the advent of Web 2.0, many people are becoming technologically savvy and attracted to internet-based activities. With the click of a button, users are now sharing more information on topics, events and issues than before. A new phenomenon in the Ghanaian journalism sphere is the advent of blogger and citizen journalism, some of whom have become niche authorities. Niche authorities have emerged through the habitual and persistent curation of news on specific topics, resulting in the steady growth and emergence of valuable contributions to news sharing. Minimal studies have been conducted on niche authorities and their role in social activism in Ghana. This study, anchored on Cialdini’s Six Principles of Persuasion (reciprocation, consistency, social proof, liking, authority and scarcity), explores the features of niche authorities, their areas of expertise, as well as their authoritative voices in the curation of news stories. Using qualitative content analysis, cyber ethnography and thematic analysis of purposively sampled social media posts of five niche authorities, the study interrogates how these niche authorities employ the six principles of persuasion on their platforms to spark conversations on development, social inclusion and gender-based issues in the country. The study discusses how niche authorities deploy the principles in social activism and further recommends nurturing and mentoring communication strategies to progressively guide the youth to become future niche authorities in news curation and news sharing.

Keywords: social activism, cialdini’s six principles of persuasion, news curation, niche authorities

Procedia PDF Downloads 50
5668 Advancements in Dielectric Materials: A Comprehensive Study on Properties, Synthesis, and Applications

Authors: M. Mesrar, T. Lamcharfi, Nor-S. Echatoui, F. Abdi

Abstract:

The solid-state reaction method was used to synthesize ferroelectric systems with lead-free properties, specifically (1-x-y)(Na₀.₅Bi₀.₅)TiO₃-xBaTiO₃-y(K₀.₅ Bi₀.₅)TiO₃. To achieve a pure perovskite phase, the optimal calcination temperature was determined to be 1000°C for 4 hours. X-ray diffraction (XRD) analysis identified the presence of the morphotropic phase boundary (MPB) in the (1-x-y)NBT xBT-yKBT ceramics for specific molar compositions, namely (0.95NBT-0.05BT, 0.84NBT-0.16KBT, and 0.79NBT-0.05BT-0.16KBT). To enhance densification, the sintering temperature was set at 1100°C for 4 hours. Scanning electron microscopy (SEM) images exhibited homogeneous distribution and dense packing of the grains in the ceramics, indicating a uniform microstructure. These materials exhibited favorable characteristics, including high dielectric permittivity, low dielectric loss, and diffused phase transition behavior. The ceramics composed of 0.79NBT-0.05BT-0.16KBT exhibited the highest piezoelectric constant (d33=148 pC/N) and electromechanical coupling factor (kp = 0.292) among all compositions studied. This enhancement in piezoelectric properties can be attributed to the presence of the morphotropic phase boundary (MPB) in the material. This study presents a comprehensive approach to improving the performance of lead-free ferroelectric systems of composition 0.79(Na₀.₅Bi₀.₅)Ti O₃-0.05BaTiO₃-0.16(K₀.₅Bi₀.₅)TiO₃.

Keywords: solid-state method, (1-x-y)NBT-xBT-yKBT, morphotropic phase boundary, Raman spectroscopy, dielectric properties

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5667 The Geographic Distribution of Complementary, Alternative, and Traditional Medicine in the United States in 2018

Authors: Janis E. Campbell

Abstract:

Most of what is known about complementary, alternative or traditional medicine (CATM) in the United States today is known from either the National Health Interview Survey a cross-sectional survey with a few questions or from small cross-sectional or cohort studies with specific populations. The broad geographical distribution in CATM use or providers is not known. For this project, we used geospatial cluster analysis to determine if there were clusters of CATM provider by county in the US. In this analysis, we used the National Provider Index to determine the geographic distribution of providers in the US. Of the 215,769 CAMT providers 211,603 resided in the contiguous US: Acupuncturist (26,563); Art, Poetry, Music and Dance Therapist (2,752); Chiropractor (89,514); Doula/Midwife (3,535); Exercise (507); Homeopath (380); Massage Therapist (36,540); Mechanotherapist (1,888); Naprapath (146); Naturopath (4,782); Nutrition (42,036); Reflexologist (522); Religious (2,438). ESRI® spatial autocorrelation was used to determine if the geographic location of CATM providers were random or clustered. For global analysis, we used Getis-Ord General G and for Local Indicators of Spatial Associations with an Optimized Hot Spot Analysis using an alpha of 0.05. Overall, CATM providers were clustered with both low and high. With Chiropractors, focusing in the Midwest, religious providers having very small clusters in the central US, and other types of CAMT focused in the northwest and west coast, Colorado and New Mexico, the great lakes areas and Florida. We will discuss some of the implications of this study, including associations with health, economic, social, and political systems.

Keywords: complementary medicine, alternative medicine, geospatial, United States

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5666 A Joint Possibilistic-Probabilistic Tool for Load Flow Uncertainty Assessment-Part I: Formulation

Authors: Morteza Aien, Masoud Rashidinejad, Mahmud Fotuhi-Firuzabad

Abstract:

As energetic and environmental issues are getting more and more attention all around the world, the penetration of distributed energy resources (DERs) mainly those harvesting renewable energies (REs) ascends with an unprecedented rate. This matter causes more uncertainties to appear in the power system context; ergo, the uncertainty analysis of the system performance is an obligation. The uncertainties of any system can be represented probabilistically or possibilistically. Since sufficient historical data about all the system variables is not available, therefore, they do not have a probability density function (PDF) and must be represented possibilistiacally. When some of system uncertain variables are probabilistic and some are possibilistic, neither the conventional pure probabilistic nor pure possibilistic methods can be implemented. Hence, a combined solution is appealed. The first of this two-paper series formulates a new possibilistic-probabilistic tool for the load flow uncertainty assessment. The proposed methodology is based on the evidence theory and joint propagation of possibilistic and probabilistic uncertainties. This possibilistic- probabilistic formulation is solved in the second companion paper in an uncertain load flow (ULF) study problem.

Keywords: probabilistic uncertainty modeling, possibilistic uncertainty modeling, uncertain load flow, wind turbine generator

Procedia PDF Downloads 545
5665 Corrosion Characteristics and Electrochemical Treatment of Heritage Silver Alloys

Authors: Ahmad N. Abu-Baker

Abstract:

This study investigated the corrosion of a group of heritage silver-copper alloy coins and their conservation treatment by potentiostatic methods. The corrosion products of the coins were characterized by a combination of scanning electron microscopy/ energy-dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD) analyses. Cathodic polarization curves, measured by linear sweep voltammetry (LSV), also identified the corrosion products and the working conditions to treat the coins using a potentiostatic reduction method, which was monitored by chronoamperometry. The corrosion products showed that the decay mechanisms were dominated by selective attack on the copper-rich phases of the silver-copper alloys, which is consistent with an internal galvanic corrosion phenomenon, which leads to the deposition of copper corrosion products on the surface of the coins. Silver chloride was also detected on the coins, which reflects selective corrosion of the silver-rich phases under different chemical environments. The potentiostatic treatment showed excellent effectiveness in determining treatment parameters and monitoring the reduction process of the corrosion products on the coins, which helped to preserve surface details in the cleaning process and to prevent over-treatment.

Keywords: silver alloys, corrosion, conservation, heritage

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5664 Design of Advanced Materials for Alternative Cooling Devices

Authors: Emilia Olivos, R. Arroyave, A. Vargas-Calderon, J. E. Dominguez-Herrera

Abstract:

More efficient cooling systems are needed to reduce building energy consumption and environmental impact. At present researchers focus mainly on environmentally-friendly magnetic materials and the potential application in cooling devices. The magnetic materials presented in this project belong to a group known as Heusler alloys. These compounds are characterized by a strong coupling between their structure and magnetic properties. Usually, a change in one of them can alter the other, which implies changes in other electronic or structural properties, such as, shape magnetic memory response or the magnetocaloric effect. Those properties and its dependence with external fields make these materials interesting, both from a fundamental point of view, as well as on their different possible applications. In this work, first principles and Monte Carlo simulations have been used to calculate exchange couplings and magnetic properties as a function of an applied magnetic field on Heusler alloys. As a result, we found a large dependence of the magnetic susceptibility, entropy and heat capacity, indicating that the magnetic field can be used in experiments to trigger particular magnetic properties in materials, which are necessary to develop solid-state refrigeration devices.

Keywords: ferromagnetic materials, magnetocaloric effect, materials design, solid state refrigeration

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5663 Isolation of Bacterial Species with Potential Capacity for Siloxane Removal in Biogas Upgrading

Authors: Ellana Boada, Eric Santos-Clotas, Alba Cabrera-Codony, Maria Martin, Lluis Baneras, Frederic Gich

Abstract:

Volatile methylsiloxanes (VMS) are a group of manmade silicone compounds widely used in household and industrial applications that end up on the biogas produced through the anaerobic digestion of organic matter in landfills and wastewater treatment plants. The presence of VMS during the biogas energy conversion can cause damage on the engines, reducing the efficiency of this renewable energy source. Non regenerative adsorption onto activated carbon is the most widely used technology to remove siloxanes from biogas, while new trends point out that biotechnology offers a low-cost and environmentally friendly alternative to conventional technologies. The first objective of this research was to enrich, isolate and identify bacterial species able to grow using siloxane molecules as a sole carbon source: anoxic wastewater sludge was used as initial inoculum in liquid anoxic enrichments, adding D4 (as representative siloxane compound) previously adsorbed on activated carbon. After several months of acclimatization, liquid enrichments were plated onto solid media containing D4 and thirty-four bacterial isolates were obtained. 16S rRNA gene sequencing allowed the identification of strains belonging to the following species: Ciceribacter lividus, Alicycliphilus denitrificans, Pseudomonas aeruginosa and Pseudomonas citronellolis which are described to be capable to degrade toxic volatile organic compounds. Kinetic assays with 8 representative strains revealed higher cell growth in the presence of D4 compared to the control. Our second objective was to characterize the community composition and diversity of the microbial community present in the enrichments and to elucidate whether the isolated strains were representative members of the community or not. DNA samples were extracted, the 16S rRNA gene was amplified (515F & 806R primer pair), and the microbiome analyzed from sequences obtained with a MiSeq PE250 platform. Results showed that the retrieved isolates only represented a minor fraction of the microorganisms present in the enrichment samples, which were represented by Alpha, Beta, and Gamma proteobacteria as dominant groups in the category class thus suggesting that other microbial species and/or consortia may be important for D4 biodegradation. These results highlight the need of additional protocols for the isolation of relevant D4 degraders. Currently, we are developing molecular tools targeting key genes involved in siloxane biodegradation to identify and quantify the capacity of the isolates to metabolize D4 in batch cultures supplied with a synthetic gas stream of air containing 60 mg m⁻³ of D4 together with other volatile organic compounds found in the biogas mixture (i.e. toluene, hexane and limonene). The isolates were used as inoculum in a biotrickling filter containing lava rocks and activated carbon to assess their capacity for siloxane removal. Preliminary results of biotrickling filter performance showed 35% of siloxane biodegradation in a contact time of 14 minutes, denoting that biological siloxane removal is a promising technology for biogas upgrading.

Keywords: bacterial cultivation, biogas upgrading, microbiome, siloxanes

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5662 Rapid Method for Low Level 90Sr Determination in Seawater by Liquid Extraction Technique

Authors: S. Visetpotjanakit, N. Nakkaew

Abstract:

Determination of low level 90Sr in seawater has been widely developed for the purpose of environmental monitoring and radiological research because 90Sr is one of the most hazardous radionuclides released from atmospheric during the testing of nuclear weapons, waste discharge from the generation nuclear energy and nuclear accident occurring at power plants. A liquid extraction technique using bis-2-etylhexyl-phosphoric acid to separate and purify yttrium followed by Cherenkov counting using a liquid scintillation counter to determine 90Y in secular equilibrium to 90Sr was developed to monitor 90Sr in the Asia Pacific Ocean. The analytical performance was validated for the accuracy, precision, and trueness criteria. Sr-90 determination in seawater using various low concentrations in a range of 0.01 – 1 Bq/L of 30 liters spiked seawater samples and 0.5 liters of IAEA-RML-2015-01 proficiency test sample was performed for statistical evaluation. The results had a relative bias in the range from 3.41% to 12.28%, which is below accepted relative bias of ± 25% and passed the criteria confirming that our analytical approach for determination of low levels of 90Sr in seawater was acceptable. Moreover, the approach is economical, non-laborious and fast.

Keywords: proficiency test, radiation monitoring, seawater, strontium determination

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5661 Status of Bio-Graphene Extraction from Biomass: A Review

Authors: Simon Peter Wafula, Ziporah Nakabazzi Kitooke

Abstract:

Graphene is a carbon allotrope made of a two-dimensional shape. This material has got a number of materials researchers’ interest due to its properties that are special compared to ordinary material. Graphene is thought to enhance a number of material properties in the manufacturing, energy, and construction industries. Many studies consider graphene to be a wonder material, just like plastic in the 21st century. This shows how much should be invested in graphene research. This review highlights the status of graphene extracted from various biomass sources together with their appropriate extraction techniques, including the pretreatment methods for a better product. The functional groups and structure of graphene extracted using several common methods of synthesis are in this paper as well. The review explores methods like chemical vapor deposition (CVD), hydrothermal, chemical exfoliation method, liquid exfoliation, and Hummers. Comparative analysis of the various extraction techniques gives an insight into each of their advantages, challenges, and potential scalability. The review also highlights the pretreatment process for biomass before carbonation for better quality of bio-graphene. The various graphene modes, as well as their applications, are in this study. Recommendations for future research for improving the efficiency and sustainability of bio-graphene are highlighted.

Keywords: exfoliation, nanomaterials, biochar, large-scale, two-dimension

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5660 CFD Prediction of the Round Elbow Fitting Loss Coefficient

Authors: Ana Paula P. dos Santos, Claudia R. Andrade, Edson L. Zaparoli

Abstract:

Pressure loss in ductworks is an important factor to be considered in design of engineering systems such as power-plants, refineries, HVAC systems to reduce energy costs. Ductwork can be composed by straight ducts and different types of fittings (elbows, transitions, converging and diverging tees and wyes). Duct fittings are significant sources of pressure loss in fluid distribution systems. Fitting losses can be even more significant than equipment components such as coils, filters, and dampers. At the present work, a conventional 90o round elbow under turbulent incompressible airflow is studied. Mass, momentum, and k-e turbulence model equations are solved employing the finite volume method. The SIMPLE algorithm is used for the pressure-velocity coupling. In order to validate the numerical tool, the elbow pressure loss coefficient is determined using the same conditions to compare with ASHRAE database. Furthermore, the effect of Reynolds number variation on the elbow pressure loss coefficient is investigated. These results can be useful to perform better preliminary design of air distribution ductworks in air conditioning systems.

Keywords: duct fitting, pressure loss, elbow, thermodynamics

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5659 Unraveling Biostimulation of Decolorized Mediators for Microbial Fuel Cell-Aided Textile Dye Decontamination

Authors: Pei-Lin Yueh, Bor-Yann Chen, Chuan-Chung Hsueh

Abstract:

This first-attempt study revealed that decolorized intermediates of azo dyes could act as redox mediators to assist wastewater (WW) decolorization due to enhancement of electron-transport phenomena. Electrochemical impedance spectra indicated that hydroxyl and amino-substituent(s) were functional group(s) as redox-mediator(s). As azo dyes are usually multiple benzene rings structured, their derived decolorized intermediates are likely to play roles of electron shuttles due to lower barrier of energy gap for electron shuttling. According to cyclic voltammetric profiles, redox-mediating characteristics of decolorized intermediates of azo dyes (e.g., RBu171, RR198, RR141, and RBk5) were clearly disclosed. With supplementation of biodecolorized metabolites of RR141 and 198, decolorization performance of could be evidently augmented. This study also suggested the optimal modes of microbial fuel cell (MFC)-assisted WW decolorization would be plug-flow or batch mode of operation with no mix. Single chamber-MFCs would be more favourable than double chamber MFCs due to non-mixing contacting reactor scheme for operation.

Keywords: redox mediators, dye decolorization, bioelectricity generation, microbial fuel cells

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5658 Platform-as-a-Service Sticky Policies for Privacy Classification in the Cloud

Authors: Maha Shamseddine, Amjad Nusayr, Wassim Itani

Abstract:

In this paper, we present a Platform-as-a-Service (PaaS) model for controlling the privacy enforcement mechanisms applied on user data when stored and processed in Cloud data centers. The proposed architecture consists of establishing user configurable ‘sticky’ policies on the Graphical User Interface (GUI) data-bound components during the application development phase to specify the details of privacy enforcement on the contents of these components. Various privacy classification classes on the data components are formally defined to give the user full control on the degree and scope of privacy enforcement including the type of execution containers to process the data in the Cloud. This not only enhances the privacy-awareness of the developed Cloud services, but also results in major savings in performance and energy efficiency due to the fact that the privacy mechanisms are solely applied on sensitive data units and not on all the user content. The proposed design is implemented in a real PaaS cloud computing environment on the Microsoft Azure platform.

Keywords: privacy enforcement, platform-as-a-service privacy awareness, cloud computing privacy

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5657 Measuring Entrepreneurial Success through Specific Sustainable Development Goals by Linking Entrepreneurship Attitude and Intentions

Authors: Mohit Taneja, Ravi Kiran, S. C. Bose

Abstract:

Entrepreneurs’ role in achieving Sustainable development goals is crucial as the growth potential of any region depends upon the number and the success rate of entrepreneurial firms. This paper is an effort to examine the relationship between Sustainable growth (SG) with Entrepreneurial attitude (EA) and Entrepreneurial intention (EI) in the context of the Indian economy. The mediation effect of EI between EA and SG has been considered. Partial least square (PLS) –Structural Equation Model (SEM) software was used to design the framework. Students enrolled in entrepreneurship courses of higher educational institutes (HEI) of Punjab, Haryana, and the National Capital Region NCR were contacted for data collection. The National Institutional Ranking Framework (NIRF) framework was used in selecting HEIs and data collected from 589 students was considered for analysis. McGee’s multi-dimensional scale for measuring ESE and the scale of Linan & Chen for measuring EI & ES (SG) was used. Results highlight that EA has a strong impact on EI (p≤ 0.001) and EI has a positive and strong relationship with SG (ES) as β value for the same is 0.683 (p≤ 0.001). The current study also reflects the mediating effect of EI among EA and ES, as the results show that the combined β value of both EA and EI (i.e.0.684*0.683= 0.467) is more than the direct influence of EA on ES (β=0.265). EA, with the mediating effect of EI can enhance the opportunity for achieving SG, which suggests that in order to increase the venture success rate and to attain SG, emphasis should be given to EI along with EA. The study has been investigated in three regions of India. Future studies can be extended to other South Asian countries for generalization.

Keywords: entrepreneurship, sustainable growth, entrepreneurship intention, entrepreneurship attitude

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5656 Comparative and Combined Toxicity of NiO and Mn₃O₄ Nanoparticles as Assessed in vitro and in vivo

Authors: Ilzira A. Minigalieva, Tatiana V. Bushueva, Eleonore Frohlich, Vladimir Panov, Ekaterina Shishkina, Boris A. Katsnelson

Abstract:

Background: The overwhelming majority of the experimental studies in the field of metal nanotoxicology have been performed on cultures of established cell lines, with very few researchers focusing on animal experiments, while a juxtaposition of conclusions inferred from these two types of research is blatantly lacking. The least studied aspect of this problem relates to characterizing and predicting the combined toxicity of metallic nanoparticles. Methods: Comparative and combined toxic effects of purposefully prepared spherical NiO and Mn₃O₄ nanoparticles (mean diameters 16.7 ± 8.2 nm and 18.4 ± 5.4 nm respectively) were estimated on cultures of human cell lines: MRC-5 fibroblasts, THP-1 monocytes, SY-SY5Y neuroblastoma cells, as well as on the latter two lines differentiated to macrophages and neurons, respectively. The combined cytotoxicity was mathematically modeled using the response surface methodology. Results: The comparative assessment of the studied NPs unspecific toxicity previously obtained in vivo was satisfactorily reproduced by the present in vitro tests. However, with respect to manganese-specific brain damage which had been demonstrated by us in animal experiment with the same NPs, the testing on neuronall cell culture showed only a certain enhancing effect of Mn₃O₄-NPs on the toxic action of NiO-NPs, while the role of the latter prevailed. Conclusion: From the point of view of the preventive toxicology, the experimental modeling of metallic NPs combined toxicity on cell cultures can give non-reliable predictions of the in vivo action’s effects.

Keywords: manganese oxide, nickel oxide, nanoparticles, in vitro toxicity

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