Search results for: supported decision-making
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1924

Search results for: supported decision-making

1774 Adsorbed Probe Molecules on Surface for Analyzing the Properties of Cu/SnO2 Supported Catalysts

Authors: Neha Thakur, Pravin S. More

Abstract:

The interaction of CO, H2 and LPG with Cu-dosed SnO2 catalysts was studied by means of Fourier transform infrared spectroscopy (FTIR). With increasing Cu loading, pronounced and progressive red shifts of the C–O stretching frequency associated with molecular CO adsorbed on the Cu/SnO2 component were observed. This decrease in n(CO) correlates with enhancement of CO dissociation at higher temperatures on Cu promoted SnO2 catalysts under conditions, where clean Cu is almost ineffective. In the conclusion, the capability of our technique is discussed, and a technique for enhancing the sensitivity in our technique is proposed.

Keywords: FTIR, spectroscopic, dissociation, n(CO)

Procedia PDF Downloads 274
1773 Preparation and Characterization of Nickel-Tungsten Nanoparticles Using Microemulsion Mediated Synthesis

Authors: S. Pal, R. Singh, S. Sivakumar, D. Kunzru

Abstract:

AOT stabilized reverse micelles of deionized water, dispersed in isooctane have been used to synthesize bimetallic nickel tungsten nanoparticles. Prepared nanoparticles were supported on γ-Al2O3 followed by calcination at 500oC. Characterizations of the nanoparticles were done by TEM, XRD, FTIR, XRF, TGA and BET. XRF results showed that this method gave good composition control with W/Ni weight ratio equal to 3.2. TEM images showed particle size of 5-10 nm. Removal of surfactant after calcination was confirmed by TGA and FTIR.

Keywords: nanoparticles, reverse micelles, nickel, tungsten

Procedia PDF Downloads 555
1772 Enhancing Project Success: A Case Study of Investment Strategies and Planning Practices in Rwanda’s Housing Projects Managed by Rwanda Social Security Board

Authors: Amina Umulisa

Abstract:

Background: Despite efforts to enhance profitability and project planning, Rwanda has experienced a decline in project success rates, notably in housing projects managed by the Rwanda Social Security Board (RSSB). This study aims to assess the impact of investment strategies and project planning practices on the performance of pension funds projects in Rwanda, focusing on housing projects by RSSB. Methods: Using descriptive and correlational research designs, this study surveyed 109 randomly selected respondents from a pool of 148 workers. Data analysis was conducted using descriptive and inferential statistics in STATA version 18. Results: Findings revealed that 54% of respondents acknowledged the importance of personnel generation. Additionally, 61% agreed with the effectiveness of training programs, and 79% supported the cost of human resource utilization. In terms of project management practices, 65.7% could determine when a project needed adjustments, 65.7% agreed with the approved budget, and 73% supported forecasted expenses. Furthermore, 68% agreed with order placement, 76.0% with using the right materials, and 64.4% with defining project scope. The study found significant associations between order placement and project quality outcomes (r=0.711, P-value <0.001), as well as with time management (Pearson was 0.701 and sing was 0.00) and cost management (r=0.885, P-value <0.001). Moreover, project time targets were found to significantly affect quality management (Pearson was 0.798, sing was 0.000), time management, and cost management (r=0.740, P-value <0.001). Conclusion: The findings highlight the positive association between the project implementation stage and quality management, indicating effective project planning practices among senior staff. However, there is a need to enhance project team collaboration and coordination to improve the performance of constructed houses.

Keywords: project success rates, investment strategies, training programs, cost management

Procedia PDF Downloads 15
1771 Approximation Property Pass to Free Product

Authors: Kankeyanathan Kannan

Abstract:

On approximation properties of group C* algebras is everywhere; it is powerful, important, backbone of countless breakthroughs. For a discrete group G, let A(G) denote its Fourier algebra, and let M₀A(G) denote the space of completely bounded Fourier multipliers on G. An approximate identity on G is a sequence (Φn) of finitely supported functions such that (Φn) uniformly converge to constant function 1 In this paper we prove that approximation property pass to free product.

Keywords: approximation property, weakly amenable, strong invariant approximation property, invariant approximation property

Procedia PDF Downloads 648
1770 Electrochemical Performance of Femtosecond Laser Structured Commercial Solid Oxide Fuel Cells Electrolyte

Authors: Mohamed A. Baba, Gazy Rodowan, Brigita Abakevičienė, Sigitas Tamulevičius, Bartlomiej Lemieszek, Sebastian Molin, Tomas Tamulevičius

Abstract:

Solid oxide fuel cells (SOFC) efficiently convert hydrogen to energy without producing any disturbances or contaminants. The core of the cell is electrolyte. For improving the performance of electrolyte-supported cells, it is desirable to extend the available exchange surface area by micro-structuring of the electrolyte with laser-based micromachining. This study investigated the electrochemical performance of cells micro machined using a femtosecond laser. Commercial ceramic SOFC (Elcogen, AS) with a total thickness of 400 μm was structured by 1030 nm wavelength Yb: KGW fs-laser Pharos (Light Conversion) using 100 kHz repetition frequency and 290 fs pulse length light by scanning with the galvanometer scanner (ScanLab) and focused with a f-Theta telecentric lens (SillOptics). The sample height was positioned using a motorized z-stage. The microstructures were formed using a laser spiral trepanning in Ni/YSZ anode supported membrane at the central part of the ceramic piece of 5.5 mm diameter at active area of the cell. All surface was drilled with 275 µm diameter holes spaced by 275 µm. The machining processes were carried out under ambient conditions. The microstructural effects of the femtosecond laser treatment on the electrolyte surface were investigated prior to the electrochemical characterisation using a scanning electron microscope (SEM) Quanta 200 FEG (FEI). The Novo control Alpha-A was used for electrochemical impedance spectroscopy on a symmetrical cell configuration with an excitation amplitude of 25 mV and a frequency range of 1 MHz to 0.1 Hz. The fuel cell characterization of the cell was examined on open flanges test setup by Fiaxell. Using nickel mesh on the anode side and au mesh on the cathode side, the cell was electrically linked. The cell was placed in a Kittec furnace with a Process IDentifier temperature controller. The wires were connected to a Solartron 1260/1287 frequency analyzer for the impedance and current-voltage characterization. In order to determine the impact of the anode's microstructure on the performance of the commercial cells, the acquired results were compared to cells with unstructured anode. Geometrical studies verified that the depth of the -holes increased linearly according to laser energy and scanning times. On the other hand, it reduced as the scanning speed increased. The electrochemical analysis demonstrates that the open circuit voltage OCV values of the two cells are equal. Further, the modified cell's initial slope reduces to 0.209 from 0.253 of the unmodified cell, revealing that the surface modification considerably decreases energy loss. Plus, the maximum power density for the cell with the microstructure and the reference cell respectively, are 1.45 and 1.16 Wcm⁻².

Keywords: electrochemical performance, electrolyte-supported cells, laser micro-structuring, solid oxide fuel cells

Procedia PDF Downloads 38
1769 Comparative Efficacy of Gas Phase Sanitizers for Inactivating Salmonella, Escherichia coli O157:H7 and Listeria monocytogenes on Intact Lettuce Heads

Authors: Kayla Murray, Andrew Green, Gopi Paliyath, Keith Warriner

Abstract:

Introduction: It is now acknowledged that control of human pathogens associated with fresh produce requires an integrated approach of several interventions as opposed to relying on post-harvest washes to remove field acquired contamination. To this end, current research is directed towards identifying such interventions that can be applied at different points in leafy green processing. Purpose: In the following the efficacy of different gas phase treatments to decontaminate whole lettuce heads during pre-processing storage were evaluated. Methods: Whole Cos lettuce heads were spot inoculated with L. monocytogenes, E. coli O157:H7 or Salmonella spp. The inoculated lettuce heads were then placed in a treatment chamber and exposed to ozone, chlorine dioxide or hydroxyl radicals at different time periods under a range of relative humidity. Survivors of the treatments were enumerated along with sensory analysis performed on the treated lettuce. Results: Ozone gas reduced L. monocytogenes by 2-log10 after ten-minutes of exposure with Salmonella and E. coli O157:H7 being decreased by 0.66 and 0.56-log cfu respectively. Chlorine dioxide gas treatment reduced L. monocytogenes and Salmonella on lettuce heads by 4 log cfu but only supported a 0.8 log cfu reduction in E. coli O157:H7 numbers. In comparison, hydroxyl radicals supported a 2.9 – 4.8 log cfu reduction of model human pathogens inoculated onto lettuce heads but required extended exposure times and relative humidity < 0.8. Significance: From the gas phase sanitizers tested, chlorine dioxide and hydroxyl radicals are the most effective. The latter process holds most promise based on the ease of delivery, worker safety and preservation of lettuce sensory characteristics. Although expose times for hydroxyl radicles was relatively long (24h) this should not be considered a limitation given the intervention is applied in store rooms or in transport containers during transit.

Keywords: gas phase sanitizers, iceberg lettuce heads, leafy green processing

Procedia PDF Downloads 379
1768 Attitudes, Experiences and Good Practices of Writing Online Course Material: A Case Study in Makerere University

Authors: Ruth Nsibirano

Abstract:

Online mode of delivery in higher institutions of learning, popularly known in some circles as e-Learning or distance education is a new phenomenon that is steadily taking root in African universities but specifically at Makerere University. For slightly over a decade, the Department of Open and Distance Learning has been offering the first generation mode of distance education. In this, learning and teaching experiences were based on the use of hard copy materials circulated through postal services in a rather correspondence mode. There were more challenges to this including high dropout rates, limited support to the learners and sustainability issues. Fortunately, the Department was supported by the Norwegian Government through a NORHED grant to “leapfrog” to the fifth generation of distance education that makes more use of educational technologies and tools. The capacity of faculty staff was gradually enhanced through a series of training to handle the upgraded structure of fifth generation distance education. The trained staff was then tasked to develop modules befitting an online delivery mode, for use on the program. This paper will present attitudes, experiences of the course writers with a view of sharing the good practices that enabled them leap from e-faculty trainees to distinct online course writers. This perspective will hopefully serve as building blocks to enhance the capacity of other upcoming distance education programs in low capacity universities and also promote the uptake of e-Education on the continent and beyond. Methodologically the findings were collected through individual interviews with the 30 course writers. In addition, semi structured questionnaires were designed to collect data on the profile, challenges and lessons from the writers. Findings show that the attitudes of course writers on project supported activities are so much tagged to the returns from their committed efforts. In conclusion, therefore, it is strategically useful to assess and selectively choose which individual to nominate for involvement at the initial stages.

Keywords: distance education, online course content, staff attitudes, best practices in online learning

Procedia PDF Downloads 223
1767 Role of Fracturing, Brecciation and Calcite Veining in Fluids Flow and Permeability Enhancement in Low-Porosity Rock Masses: Case Study of Boulaaba Aptian Dolostones, Kasserine, Central Tunisia

Authors: Mohamed Khali Zidi, Mohsen Henchiri, Walid Ben Ahmed

Abstract:

In the context of a hypogene hydrothermal travertine system, including low-porosity brittle bedrock and rock-mass permeability in Aptian dolostone of Boulaaba, Kasserine is enhanced through faulting and fracturing. This permeability enhancement related to the deformation modes along faults and fractures is likely to be in competition with permeability reduction when microcracks, fractures, and faults all become infilled with breccias and low-permeability hydrothermal precipitates. So that, fault continual or intermittent reactivation is probably necessary for them to keep their potential as structural high-permeability conduits. Dilational normal faults in strong mechanical stratigraphy associated with fault segments with dip changes are sites for porosity and permeability in groundwater infiltration and flow, hydrocarbon reservoirs, and also may be important sources of mineralization. The brecciation mechanism through dilational faulting and gravitational collapse originates according to hosting lithologies chaotic clast-supported breccia in strong lithologies such as sandstones, limestones, and dolostones, and matrix-supported cataclastic in weaker lithologies such as marls and shales. Breccias contribute to controlling fluid flow when the porosity is sealed either by low-permeability hydrothermal precipitates or by fine matrix materials. All these mechanisms of fault-related rock-mass permeability enhancement and reduction can be observed and analyzed in the region of Sidi Boulaaba, Kasserine, central Tunisia, where dilational normal faulting occurs in mechanical strong dolostone layering alternating with more weak marl and shale lithologies, has originated a variety of fault voids (fluid conduits) breccias (chaotic, crackle and mosaic breccias) and carbonate cement.

Keywords: travertine, Aptian dolostone, Boulaaba, fracturing

Procedia PDF Downloads 27
1766 Priority Sites for Deforested and Degraded Mountain Restoration Projects in North Korea

Authors: Koo Ja-Choon, Seok Hyun-Deok, Park So-Hee

Abstract:

Even though developed countries have supported aid projects for restoring degraded and deforested mountain, recent North Korean authorities announced that North Korean forest is still very serious. Last 12 years, more than 16 thousand ha of forest were destroyed. Most of previous researches concluded that food and fuel problems should be solved for preventing people from deforesting and degrading forest in North Korea. It means that mountain restoration projects such as A/R(afforestation/reforestation) and REDD(Reducing Emissions from Deforestation and Forest Degradation) project should be implemented with the agroforestry and the forest tending project. Because agroforestry and the forest tending can provide people in the project area with foods and fuels, respectively. Especially, Agroforestry has been operated well with the support of Swiss agency of Development and cooperation since 2003. This paper aims to find the priority sites for mountain restoration project where all types of projects including agroforesty can be implemented simultaneously. We tried to find the primary counties where the areas of these activities were distributed widely and evenly. Recent spatial data of 186 counties representing altitude, gradient and crown density were collected from World Forest Watch. These 3 attributes were used to determine the type of activities; A/R, REDD, Agroforestry and forest tending project. Finally, we calculated the size of 4 activities in 186 counties by using GIS technique. Result shows that Chongjin in Hamgyeongbuk-do, Hoeryong in Hamgyeongbuk-do and Tongchang in Pyeonganbuk-do are on the highest priority of counties. Most of feasible counties whose value of richness and uniformity were greater than the average were located near the eastern coast of North Korea. South Korean government has not supported any aid projects in North Korea since 2010. Recently, South Korea is trying to continue the aid projects for North Korea. Forest project which is not affected by the political situation between North- and South- Korea can be considered as a priority activities. This result can be used when South Korean government determine the priority sites for North Korean mountain restoration project in near future.

Keywords: agroforestry, forest restoration project, GIS, North Korea, priority

Procedia PDF Downloads 298
1765 Preparation and Characterization of Supported Metal Nanocrystal Using Simple Heating Method for Renewable Diesel Synthesis from Nyamplung Oil (Calophyllum inophyllum Oil)

Authors: Aida Safiera, Andika Dwi Rubyantoro, Muhammad Bagus Prakasa

Abstract:

Indonesia’s needs of diesel oil each year are increasing and getting urge. However, that problems are not supported by the amount of oil production that still low and also influenced by the fact of oil reserve is reduced. Because of that, the government prefers to import from other countries than fulfill the needs of diesel. To anticipate that problem, development of fuel based on renewable diesel is started. Renewable diesel is renewable alternative fuel that is hydrocarbon derivative from decarbonylation of non-edible oil. Indonesia is rich with natural resources, including nyamplung oil (Calophyllum inophyllum oil) and zeolite. Nyamplung oil (Calophyllum inophyllum oil) has many stearic acids which are useful on renewable diesel synthesis meanwhile zeolite is cheap. Zeolite is many used on high temperature reaction and cracking process on oil industry. Zeolite also has advantages which are a high crystallization, surface area and pores. In this research, the main focus that becomes our attention is on preparation and characterization of metal nanocrystal. Active site that used in this research is Nickel Molybdenum (NiMo). The advantage of nanocrystal with nano scale is having larger surface area. The synthesis of metal nanocrystal will be done with conventional preparation modification method that is called simple heating. Simple heating method is a metal nanocrystal synthesis method using continuous media which is polymer liquid. This method is a simple method and produces a small particles size in a short time. Influence of metal nanocrystal growth on this method is the heating profile. On the synthesis of nanocrystal, the manipulated variables are temperature and calcination time. Results to achieve from this research are diameter size on nano scale (< 100 nm) and uniform size without any agglomeration. Besides that, the conversion of synthesis of renewable diesel is high and has an equal specification with petroleum diesel. Catalyst activities are tested by FT-IR and GC-TCD on decarbonylation process with a pressure 15 bar and temperature 375 °C. The highest conversion from this reaction is 35% with selectivity around 43%.

Keywords: renewable diesel, simple heating, metal nanocrystal, NiMo, zeolite

Procedia PDF Downloads 202
1764 Production and Purification of Monosaccharides by Hydrolysis of Sugar Cane Bagasse in an Ionic Liquid Medium

Authors: T. R. Bandara, H. Jaelani, G. J. Griffin

Abstract:

The conversion of lignocellulosic waste materials, such as sugar cane bagasse, to biofuels such as ethanol has attracted significant interest as a potential element for transforming transport fuel supplies to totally renewable sources. However, the refractory nature of the cellulosic structure of lignocellulosic materials has impeded progress on developing an economic process, whereby the cellulose component may be effectively broken down to glucose monosaccharides and then purified to allow downstream fermentation. Ionic liquid (IL) treatment of lignocellulosic biomass has been shown to disrupt the crystalline structure of cellulose thus potentially enabling the cellulose to be more readily hydrolysed to monosaccharides. Furthermore, conventional hydrolysis of lignocellulosic materials yields byproducts that are inhibitors for efficient fermentation of the monosaccharides. However, selective extraction of monosaccharides from an aqueous/IL phase into an organic phase utilizing a combination of boronic acids and quaternary amines has shown promise as a purification process. Hydrolysis of sugar cane bagasse immersed in an aqueous solution with IL (1-ethyl-3-methylimidazolium acetate) was conducted at different pH and temperature below 100 ºC. It was found that the use of a high concentration of hydrochloric acid to acidify the solution inhibited the hydrolysis of bagasse. At high pH (i.e. basic conditions), using sodium hydroxide, catalyst yields were reduced for total reducing sugars (TRS) due to the rapid degradation of the sugars formed. For purification trials, a supported liquid membrane (SLM) apparatus was constructed, whereby a synthetic solution containing xylose and glucose in an aqueous IL phase was transported across a membrane impregnated with phenyl boronic acid/Aliquat 336 to an aqueous phase. The transport rate of xylose was generally higher than that of glucose indicating that a SLM scheme may not only be useful for purifying sugars from undesirable toxic compounds, but also for fractionating sugars to improve fermentation efficiency.

Keywords: biomass, bagasse, hydrolysis, monosaccharide, supported liquid membrane, purification

Procedia PDF Downloads 227
1763 Place-Making Theory behind Claremont Court

Authors: Sandra Costa-Santos, Nadia Bertolino, Stephen Hicks, Vanessa May, Camilla Lewis

Abstract:

This paper aims to elaborate the architectural theory on place-making that supported Claremont Court housing scheme (Edinburgh, United Kingdom). Claremont Court (1959-62) is a large post-war mixed development housing scheme designed by Basil Spence, which included ‘place-making’ as one of its founding principles. Although some stylistic readings of the housing scheme have been published, the theory on place-making that allegedly ruled the design has yet to be clarified. The architecture allows us to mark or make a place within space in order to dwell. Under the framework of contemporary philosophical theories of place, this paper aims to explore the relationship between place and dwelling through a cross-disciplinary reading of Claremont Court, with a view to develop an architectural theory on place-making. Since dwelling represents the way we are immersed in our world in an existential manner, this theme is not just relevant for architecture but also for philosophy and sociology. The research in this work is interpretive-historic in nature. It examines documentary evidence of the original architectural design, together with relevant literature in sociology, history, and architecture, through the lens of theories of place. First, the paper explores how the dwelling types originally included in Claremont Court supported ideas of dwelling or meanings of home. Then, it traces shared space and social ties in order to study the symbolic boundaries that allow the creation of a collective identity or sense of belonging. Finally, the relation between the housing scheme and the supporting theory is identified. The findings of this research reveal Scottish architect Basil Spence’s exploration of the meaning of home, as he changed his approach to the mass housing while acting as President of the Royal Incorporation of British Architects (1958-60). When the British Government was engaged in various ambitious building programmes, he sought to drive architecture to a wider socio-political debate as president of the RIBA, hence moving towards a more ambitious and innovative socio-architectural approach. Rather than trying to address the ‘genius loci’ with an architectural proposition, as has been stated, the research shows that the place-making theory behind the housing scheme was supported by notions of community-based on shared space and dispositions. The design of the housing scheme was steered by a desire to foster social relations and collective identities, rather than by the idea of keeping the spirit of the place. This research is part of a cross-disciplinary project funded by the Arts and Humanities Research Council. The findings present Claremont Court as a signifier of Basil Spence’s attempt to address the post-war political debate on housing in United Kingdom. They highlight the architect’s theoretical agenda and challenge current purely stylistic readings of Claremont Court as they fail to acknowledge its social relevance.

Keywords: architectural theory, dwelling, place-making, post-war housing

Procedia PDF Downloads 234
1762 Analysis and Design of Offshore Met Mast Supported on Jacket Substructure

Authors: Manu Manu, Pardha J. Saradhi, Ramana M. V. Murthy

Abstract:

Wind Energy is accepted as one of the most developed, cost effective and proven renewable energy technologies to meet increasing electricity demands in a sustainable manner. Preliminary assessment studies along Indian Coastline by Ministry of New and Renewable Energy have indicated prospects for development of offshore wind power along Tamil Nadu Coast, India. The commercial viability of a wind project mainly depends on wind characteristics on site. Hence, it is internationally recommended to perform site-specific wind resource assessment based on two years’ wind profile as a part of the feasibility study. Conventionally, guy wire met mast are used onshore for the collection of wind profile. Installation of similar structure in offshore requires complex marine spread and are very expensive. In the present study, an attempt is made to develop 120 m long lattice tower supported on the jacket, piled to the seabed at Rameshwaram, Tamil Nadu, India. Offshore met-masts are subjected to combined wind and hydrodynamic loads, and these lateral loads should be safely transferred to soil. The wind loads are estimated based on gust factor method, and the hydrodynamic loads are estimated by Morison’s equation along with suitable wave theory. The soil is modeled as three nonlinear orthogonal springs based on API standards. The structure configuration and optimum member sizes are obtained for extreme cyclone events. The dynamic behavior of mast under coupled wind and wave loads is also studied. The static responses of a mast with jacket type offshore platform have been studied using a frame model in SESAM. It is found from the study that the maximum displacement at the top of the mast for the random wave is 0.003 m and that of the tower for wind is 0.08 m during the steady state. The dynamic analysis results indicate that the structure is safe against coupled wind and wave loading.

Keywords: offshore wind, mast, static, aerodynamic load, hydrodynamic load

Procedia PDF Downloads 179
1761 Effect of N2-cold Plasma Treatment of Carbon Supports on the Activity of Pt3Pd3Sn2/C Towards the Dimethyl Ether Oxidation

Authors: Medhanie Gebremedhin Gebru, Alex Schechter

Abstract:

Dimethyl ether (DME) possesses several advantages over other small organic molecules such as methanol, ethanol, and ammonia in terms of providing higher energy density, being less toxic, and having lower Nafion membrane crossover. However, the absence of an active and stable catalyst has been the bottleneck that hindered the commercialization of direct DME fuel cells. A Vulcan XC72 carbon-supported ternary metal catalyst, Pt₃Pd₃Sn₂/C is reported to have yielded the highest specific power density (90 mW mg-¹PGM) as compared to other catalysts tested fordirect DME fuel cell (DDMEFC). However, the micropores and sulfur groups present in Vulcan XC72 hinder the fuel utilization by causing Pt agglomeration and sulfur poisoning. Vulcan XC72 having a high carbon sp³ hybridization content, is also prone to corrosion. Therefore, carbon supports such as multi-walled carbon nanotube (MWCNT), black pearl 2000 (BP2000), and their cold N2 plasma-treated counterpartswere tested to further enhance the activity of the catalyst, and the outputs with these carbons were compared with the originally used support. Detailed characterization of the pristine and carbon supports was conducted. Electrochemical measurements in three-electrode cells and laboratory prototype fuel cells were conducted.Pt₃Pd₃Sn₂/BP2000 exhibited excellent performance in terms of electrochemical active surface area (ECSA), peak current density (jp), and DME oxidation charge (Qoxi). The effect of the plasma activation on the activity improvement was observed only in the case of MWCNT while having little or no effect on the other carbons. A Pt₃Pd₃Sn₂ supported on the optimized mixture of carbons containing 75% plasma-activated MWCNT and 25% BP2000 (Pt₃Pd₃Sn₂/75M25B) provided the highest reported power density of 117 mW mg-1PGM using an anode loading of1.55 mgPGMcm⁻².

Keywords: DME, DDMEFC, ternary metal catalyst, carbon support, plasma activation

Procedia PDF Downloads 116
1760 Behavior of Laminated Plates under Mechanical Loading

Authors: Mahmoudi Noureddine

Abstract:

In this study the use of two variable refined plate theories of laminated composite plates to static response of laminated plates. The plate theory accounts for parabolic distribution of the transverse shear strains, and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factor. The validity of the present theory is demonstrated by comparison with solutions available in the literature and finite element method. The result is presented for the static response of simply supported rectangular plates under uniform sinusoidal mechanical loadings.

Keywords: bending, composite, laminate, plates, fem

Procedia PDF Downloads 377
1759 Inheritance, Stability, and Validation of Provitamin a Markers in Striga Hermonthica-Resistant Maize

Authors: Fiston Masudi Tambwe, Lwanga Charles, Arfang Badji, Unzimai Innocent

Abstract:

The development of maize varieties combining Provitamin A (PVA), high yield, and Striga resistance is an effective and affordable strategy to contribute to food security in sub-Saharan Africa, where maize is a staple food crop. There has been limited research on introgressing PVA genes into Striga-resistant maize genotypes. The objectives of this study were to: i) determine the mode of gene action controlling PVA carotenoid accumulation in Striga-resistant maize, ii) identify Striga-resistant maize hybrids with high PVA content and stable yield, and iii) validate the presence of PVA functional markers in offspring. Six elite, Striga-resistant inbred females were crossed with six high-PVA inbred males in a North Carolina Design II and their offspring were evaluated in four environments, following a 5x8 alpha lattice design with four hybrid checks. Results revealed that both additive and non-additive gene action control carotenoid accumulation in the present study, with a predominance of non-additive gene effects for PVA. Hybrids STR1004xCLHP0352 and STR1004xCLHP0046 - identified as Striga-resistant because they supported fewer Striga plants – were the highest-yielding genotypes with a moderate PVA concentration of 5.48 and 5.77 µg/g, respectively. However, those two hybrids were not stable in terms of yield across all environments. Hybrid STR1007xCLHP0046, however, supported fewer Striga plants, had a yield of 4.52 T/ha, a PVA concentration of 4.52 µg/g, and was also stable. Gel-based marker systems of CrtRB1 and LCYE were used to screen the hybrids and favorable alleles of CrtRB1 primers were detected in 20 hybrids, confirming good levels of PVA carotenoids. Hybrids with favorable alleles of LCYE had the highest concentration of non-PVA carotenoids. These findings will contribute to the development of high-yielding PVA-rich maize varieties in Uganda.

Keywords: gene action, stability, striga resistance, provitamin A markers, beta-carotene hydroxylase 1, CrtRB1, beta-carotene, beta-cryptoxanthin, lycopene epsilon cyclase, LCYE

Procedia PDF Downloads 38
1758 Approaches to Integrating Entrepreneurial Education in School Curriculum

Authors: Kofi Nkonkonya Mpuangnan, Samantha Govender, Hlengiwe Romualda Mhlongo

Abstract:

In recent years, a noticeable and worrisome pattern has emerged in numerous developing nations which is a steady and persistent rise in unemployment rates. This escalation of economic struggles has become a cause of great concern for parents who, having invested significant resources in their children's education, harboured hopes of achieving economic prosperity and stability for their families through secure employment. To effectively tackle this pressing unemployment issue, it is imperative to adopt a holistic approach, and a pivotal aspect of this approach involves incorporating entrepreneurial education seamlessly into the entire educational system. In this light, the authors explored approaches to integrating entrepreneurial education into school curriculum focusing on the following questions. How can an entrepreneurial mindset among learners be promoted in school? And how far have pedagogical approaches improved entrepreneurship in schools? To find answers to these questions, a systematic literature review underpinned by Human Capital Theory was adopted. This method was supported by the three stages of guidelines like planning, conducting, and reporting. The data were specifically sought from publishers with expansive coverage of scholarly literature like Sage, Taylor & Francis, Emirate, and Springer, covering publications from 1965 to 2023. The search was supported by two broad terms such as promoting entrepreneurial mindset in learners and pedagogical strategies for enhancing entrepreneurship. It was found that acquiring an entrepreneurial mindset through an innovative classroom environment, resilience, and guest speakers and industry experts. Also, teachers can promote entrepreneurial education through the adoption of pedagogical approaches such as hands-on learning and experiential activities, role-playing, business simulation games and creative and innovative teaching. It was recommended that the Ministry of Education should develop tailored training programs and workshops aimed at empowering educators with the essential competencies and insights to deliver impactful entrepreneurial education.

Keywords: education, entrepreneurship, school curriculum, pedagogical approaches, integration

Procedia PDF Downloads 55
1757 Arsenic (III) Removal by Zerovalent Iron Nanoparticles Synthesized with the Help of Tea Liquor

Authors: Tulika Malviya, Ritesh Chandra Shukla, Praveen Kumar Tandon

Abstract:

Traditional methods of synthesis are hazardous for the environment and need nature friendly processes for the treatment of industrial effluents and contaminated water. Use of plant parts for the synthesis provides an efficient alternative method. In this paper, we report an ecofriendly and nonhazardous biobased method to prepare zerovalent iron nanoparticles (ZVINPs) using the liquor of commercially available tea. Tea liquor as the reducing agent has many advantages over other polymers. Unlike other polymers, the polyphenols present in tea extract are nontoxic and water soluble at room temperature. In addition, polyphenols can form complexes with metal ions and thereafter reduce the metals. Third, tea extract contains molecules bearing alcoholic functional groups that can be exploited for reduction as well as stabilization of the nanoparticles. Briefly, iron nanoparticles were prepared by adding 2.0 g of montmorillonite K10 (MMT K10) to 5.0 mL of 0.10 M solution of Fe(NO3)3 to which an equal volume of tea liquor was then added drop wise over 20 min with constant stirring. The color of the mixture changed from whitish yellow to black, indicating the formation of iron nanoparticles. The nanoparticles were adsorbed on montmorillonite K10, which is safe and aids in the separation of hazardous arsenic species simply by filtration. Particle sizes ranging from 59.08±7.81 nm were obtained which is confirmed by using different instrumental analyses like IR, XRD, SEM, and surface area studies. Removal of arsenic was done via batch adsorption method. Solutions of As(III) of different concentrations were prepared by diluting the stock solution of NaAsO2 with doubly distilled water. The required amount of in situ prepared ZVINPs supported on MMT K10 was added to a solution of desired strength of As (III). After the solution had been stirred for the preselected time, the solid mass was filtered. The amount of arsenic [in the form of As (V)] remaining in the filtrate was measured using ion chromatograph. Stirring of contaminated water with zerovalent iron nanoparticles supported on montmorillonite K10 for 30 min resulted in up to 99% removal of arsenic as As (III) from its solution at both high and low pH (2.75 and 11.1). It was also observed that, under similar conditions, montmorillonite K10 alone provided only <10% removal of As(III) from water. Adsorption at low pH with precipitation at higher pH has been proposed for As(III) removal.

Keywords: arsenic removal, montmorillonite K10, tea liquor, zerovalent iron nanoparticles

Procedia PDF Downloads 97
1756 Increasing Productivity through Lean Manufacturing Principles and Tools: A Successful Rail Welding Plant Case

Authors: T. A. Faria, C. C. Toniolo, L. F. Ribeiro

Abstract:

In order to satisfy the costumer’s needs, many sectors of industry and services has been spending major effort to make its processes more efficient. Facing a situation, when its production cannot cover the demand, the traditional way to achieve the production required involves, mostly, adding shifts, workforce, or even more machines. This paper narrates how lean manufacturing supported a dramatic increase of productivity at a rail welding plant in Brazil in order to meet the demand for the next years.

Keywords: productivity, lean manufacturing, rail welding, value stream mapping

Procedia PDF Downloads 327
1755 Searching the Efficient Frontier for the Coherent Covering Location Problem

Authors: Felipe Azocar Simonet, Luis Acosta Espejo

Abstract:

In this article, we will try to find an efficient boundary approximation for the bi-objective location problem with coherent coverage for two levels of hierarchy (CCLP). We present the mathematical formulation of the model used. Supported efficient solutions and unsupported efficient solutions are obtained by solving the bi-objective combinatorial problem through the weights method using a Lagrangean heuristic. Subsequently, the results are validated through the DEA analysis with the GEM index (Global efficiency measurement).

Keywords: coherent covering location problem, efficient frontier, lagragian relaxation, data envelopment analysis

Procedia PDF Downloads 306
1754 Mapping the Adoption Process of Communication Technology to Maintain Contact between Older Adults with Intellectual Disability in Out-of-home Residence and Their Families: A Multiple-Case Study Research

Authors: Carmit Noa Shpigelman, Michal Isaacson

Abstract:

Over the last decades, the improvement in welfare and health services and the increase in awareness of the needs of people with intellectual disability has led to an increase in their life expectancy, and many of them enter into old age. Furthermore, many older adults with intellectual disability live in out-of-home residence. This situation, in addition to the parents' aging process as the main caregivers, may lead to a reduction in contact with the family and, as a result, decreased level of the residents' (older adults with intellectual disability) well-being. A plausible solution for this condition may be using communication technologies. Previous studies indicate that using communication technologies among older adults contributes to maintaining the relationship with others, decreasing the older adult's sense of loneliness, and increasing their level of well-being. Using communication technologies may be especially valuable for older adults in the current global pandemic of COVID-19 and the associated restrictions of social distancing. However, to date, research on using communication technologies among people with intellectual disability has focused on younger cohorts. Moreover, research on the adoption of technologies among older adults with intellectual disability has focused more on assistive technologies and less on communication technologies. To address these practice and research gaps, the present study focuses on the adoption process of communication technology among older adults with intellectual disability (over the age of 45 years) who live in supported accommodation. Fifteen residents participated in an intervention program where they received a tablet with a video communication application and through which they were able to contact their families. A multiple-case study methodology was applied to capture the experiences, including barriers and needs, of the residents from three perspectives: the resident, the family member, and a staff member from the residential setting. The data was collected via quantitative and qualitative measures at different time points over the intervention. The findings demonstrate the contribution of using communication technology for the well-being of older adults with intellectual disability in supported accommodation. The findings also map the adoption process among this population, including pitfalls. The present study contributes to developing best practices on how to accommodate communication technologies to older adults with intellectual disability for maintaining contact with others.

Keywords: adoption, aging, communication, intellectual disability, technology

Procedia PDF Downloads 198
1753 Assessing the Eutrophication Risk in the Suat Uğurlu Dam Lake by Evaluation of Trophic Variables

Authors: Bilge Aydın Er, Yuksel Ardalı

Abstract:

In Ayvacık village, 80-90% of the population is engaged in agriculture. The pollution was adversely affecting the properties of agricultural origin of the lake. This study is to determine pollution caused by unwanted changes in the Suat Ugurlu Dam Lake has been launched to monitor. Yesilirmak basin is located in the proximal part of the Black Sea. Therefore it was exposed to impact many pollution. In this study, sediment samples from selected points along the lake was made on the analysis. This work was supported by the results of water analyzes. It is clear that urgent measures should be taken to the area of water management

Keywords: eutrophication, Black sea, lake, pollution

Procedia PDF Downloads 363
1752 Effect of Fabrication Errors on High Frequency Filter Circuits

Authors: Wesam Ali

Abstract:

This paper provides useful guidelines to the circuit designers on the magnitude of fabrication errors in multilayer millimeter-wave components that are acceptable and presents data not previously reported in the literature. A particularly significant error that was quantified was that of skew between conductors on different layers, where it was found that a skew angle of only 0.1° resulted in very significant changes in bandwidth and insertion loss. The work was supported by a detailed investigation on a 35GHz, multilayer edge-coupled band-pass filter, which was fabricated on alumina substrates using photoimageable thick film process.

Keywords: fabrication errors, multilayer, high frequency band, photoimagable technology

Procedia PDF Downloads 444
1751 A Semantic E-Learning and E-Assessment System of Learners

Authors: Wiem Ben Khalifa, Dalila Souilem, Mahmoud Neji

Abstract:

The evolutions of Social Web and Semantic Web lead us to ask ourselves about the way of supporting the personalization of learning by means of intelligent filtering of educational resources published in the digital networks. We recommend personalized courses of learning articulated around a first educational course defined upstream. Resuming the context and the stakes in the personalization, we also suggest anchoring the personalization of learning in a community of interest within a group of learners enrolled in the same training. This reflection is supported by the display of an active and semantic system of learning dedicated to the constitution of personalized to measure courses and in the due time.

Keywords: Semantic Web, semantic system, ontology, evaluation, e-learning

Procedia PDF Downloads 298
1750 An Examination of Factors Leading to Knowledge-Sharing Behavior of Sri Lankan Bankers

Authors: Eranga N. Somaratna, Pradeep Dharmadasa

Abstract:

In the current competitive environment, the factors leading to organization success are not limited to the investment of capital, labor, and raw material, but in the ability of knowledge innovation from all the members of an organization. However, knowledge on its own cannot provide organizations with its promised benefits unless it is shared, as organizations are increasingly experiencing unsuccessful knowledge sharing efforts. In such a backdrop and due to the dearth of research in this area in the South Asian context, the study set forth to develop an understanding of the factors that influence knowledge-sharing behavior within an organizational framework, using widely accepted social psychology theories. The purpose of the article is to discover the determinants of knowledge-sharing intention and actual knowledge sharing behaviors of bank employees in Sri Lanka using an aggregate model. Knowledge sharing intentions are widely discussed in literature through the application of Ajzen’s Theory of planned behavior (TPB) and Theory of Social Capital (SCT) separately. Both the theories are rich to explain knowledge sharing intention of workers with limitations. The study, therefore, combines the TPB with SCT in developing its conceptual model. Data were collected through a self-administrated paper-based questionnaire of 199 bank managers from 6 public and private banks of Sri Lanka and analyzed the suggested research model using Structural Equation Modelling (SEM). The study supported six of the nine hypotheses, where Attitudes toward Knowledge Sharing Behavior, Perceived Behavioral Control, Trust, Anticipated Reciprocal Relationships and Actual Knowledge Sharing Behavior were supported while Organizational Climate, Sense of Self-Worth and Anticipated Extrinsic Rewards were not, in determining knowledge sharing intentions. Furthermore, the study investigated the effect of demographic factors of bankers (age, gender, position, education, and experiences) to the actual knowledge sharing behavior. However, findings should be confirmed using a larger sample, as well as through cross-sectional studies. The results highlight the need for theoreticians to combined TPB and SCT in understanding knowledge workers’ intentions and actual behavior; and for practitioners to focus on the perceptions and needs of the individual knowledge worker and the need to cultivate a culture of sharing knowledge in the organization for their mutual benefit.

Keywords: banks, employees behavior, knowledge management, knowledge sharing

Procedia PDF Downloads 110
1749 Effect of R&D Human Capital Support for SMEs: An Analysis of Smes Support Program in South Korea

Authors: Misun Kim, Beomsoo Park

Abstract:

Korean government has strongly supported SMEs financially and technically. It has also changed R&D manpower management so that SMEs can benefit from the knowledge of highly qualified experts. This study evaluates the impacts of such policy on SMEs and analyzes the factors affecting the growth of the firms. Then we compare the characteristics of high growth companies to general companies. This factors could be use in the future for identifying firms that would significantly benefit from manpower help.

Keywords: dispatch human Ccapital, high growth, science and technology policy, SMEs

Procedia PDF Downloads 280
1748 Volatile Organic Compounds (VOCS) Destruction by Catalytic Oxidation for Environmental Applications

Authors: Mohammed Nasir Kajama, Ngozi Claribelle Nwogu, Edward Gobina

Abstract:

Pt/γ-Al2O3 membrane catalysts were prepared via an evaporative-crystallization deposition method. The obtained Pt/γ-Al2O3 catalyst activity was tested after characterization (SEM-EDAX observation, BET measurement, permeability assessment) in the catalytic oxidation of selected volatile organic compound (VOC) i.e. propane, fed in mixture of oxygen. The VOC conversion (nearly 90%) obtained by varying the operating temperature showed that flow-through membrane reactor might do better in the abatement of VOCs.

Keywords: VOC combustion, flow-through membrane reactor, platinum supported alumina catalysts

Procedia PDF Downloads 509
1747 The Preparation of High Surface Area Ni/MgAl2O4 Catalysts for Syngas Methanation

Authors: Jingyu Zhou, Hongfang Ma, Haitao Zhang, Weiyong Ying

Abstract:

High surface area MgAl2O4 supported Nickel catalysts with PVA loadings varying from 0% to 15% were prepared by precipitation and impregnation method. The catalysts were characterized by low temperature N2 adsorption/desorption, X-ray diffraction and H2 temperature programmed reduction. Compared with Ni/γ-Al2O3 catalyst, Ni/MgAl2O4 catalysts exhibited higher activity and selectivity in high temperature. Among the catalysts, Ni/MgAl2O4-5P with 5 wt% PVA showed the best performance, and achieved 95% CO conversion and 96% CH4 selectivity at 600°C, 2.0 MPa, and a WHSV of 12,000 mL·g⁻¹.h⁻¹. It also maintained good stability in 50h life test.

Keywords: methanation, MgAl2O4 support, PVA, high surface area

Procedia PDF Downloads 296
1746 Fabric Softener Deposition on Cellulose Nanocrystals and Cotton Fibers

Authors: Evdokia K. Oikonomou, Nikolay Christov, Galder Cristobal, Graziana Messina, Giovani Marletta, Laurent Heux, Jean-Francois Berret

Abstract:

Fabric softeners are aqueous formulations that contain ~10 wt. % double tailed cationic surfactants. Here, a formulation in which 50% surfactant was replaced with low quantities of natural guar polymers was developed. Thanks to the reduced surfactant quantity this product has less environmental impact while the guars presence was found to maintain the product’s performance. The objective of this work is to elucidate the effect of the guar polymers on the softener deposition and the adsorption mechanism on the cotton surface. The surfactants in these formulations are assembled into large distributed (0.1 – 1 µm) vesicles that are stable in the presence of guars and upon dilution. The effect of guars on the vesicles adsorption on cotton was first estimated by using cellulose nanocrystals (CNC) as a stand-in for cotton. The dispersion of CNC in water permits to follow the interaction between the vesicles, guars, and CNC in the bulk. It was found that guars enhance the deposition on CNC and that the vesicles are deposited intactly on the fibers driven by electrostatics. The mechanism of the vesicles/guars adsorption on cellulose fibers was identified by quartz crystal microbalance with dissipation monitoring. It was found that the guars increase the surfactant deposited quantity, in agreement with the results in the bulk. Also, the structure of the adsorbed surfactant on the fibers' surfaces (vesicle or bilayer) was influenced by the guars presence. Deposition studies on cotton fabrics were also conducted. Attenuated total reflection and scanning electron microscopy were used to study the effect of the polymers on this deposition. Finally, fluorescent microscopy was used to follow the adsorption of surfactant vesicles, labeled with a fluorescent dye, on cotton fabrics in water. It was found that, in the presence or not of polymers, the surfactant vesicles are adsorbed on fiber maintaining their vesicular structure in water (supported vesicular bilayer structure). The guars influence this process. However, upon drying the vesicles are transformed into bilayers and eventually wrap the fibers (supported lipid bilayer structure). This mechanism is proposed for the adsorption of vesicular conditioner on cotton fiber and can be affected by the presence of polymers.

Keywords: cellulose nanocrystals, cotton fibers, fabric softeners, guar polymers, surfactant vesicles

Procedia PDF Downloads 152
1745 Implication of Soil and Seismic Ground Motion Variability on Dynamic Pile Group Impedance for Bridges

Authors: Muhammad Tariq Chaudhary

Abstract:

Bridges constitute a vital link in a transportation system and their functionality after an earthquake is critical in reducing disruption to social and economic activities of the society. Bridges supported on pile foundations are commonly used in many earthquake-prone regions. In order to properly design or investigate the performance of such structures, it is imperative that the effect of soil-foundation-structure interaction be properly taken into account. This study focused on the influence of soil and seismic ground motion variability on the dynamic impedance of pile-group foundations typically used for medium-span (about 30 m) urban viaduct bridges. Soil profiles corresponding to various AASHTO soil classes were selected from actual data of such bridges and / or from the literature. The selected soil profiles were subjected to 1-D wave propagation analysis to determine effective values of soil shear modulus and damping ratio for a suite of properly selected actual seismic ground motions varying in PGA from 0.01g to 0.64g, and having variable velocity and frequency content. The effective values of the soil parameters were then employed to determine the dynamic impedance of pile groups in horizontal, vertical and rocking modes in various soil profiles. Pile diameter was kept constant for bridges in various soil profiles while pile length and number of piles were changed based on AASHTO design requirements for various soil profiles and earthquake ground motions. Conclusions were drawn regarding variability in effective soil shear modulus, soil damping, shear wave velocity and pile group impedance for various soil profiles and ground motions and its implications for design and evaluation of pile-supported bridges. It was found that even though the effective soil parameters underwent drastic variation with increasing PGA, the pile group impedance was not affected much in properly designed pile foundations due to the corresponding increase in pile length or increase in a number of piles or both when subjected to increasing PGA or founded in weaker soil profiles.

Keywords: bridge, pile foundation, dynamic foundation impedance, soil profile, shear wave velocity, seismic ground motion, seismic wave propagation

Procedia PDF Downloads 283