Search results for: structured glass surfaces
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4732

Search results for: structured glass surfaces

4012 Community Music in Puerto Rico

Authors: Francisco Luis Reyes

Abstract:

The multiple-case study explores the intricacies of three Puerto Rican Community Music (CM) initiatives. This research concentrates on the teaching and learning dynamics of three of the nation’s traditional musical genres, Plena, Bomba, and Música Jíbara, which have survived for centuries through oral transmission and enculturation in community settings. Accordingly, this research focuses on how music education is carried out in Puerto Rican CM initiatives that foster and preserve the country’s traditional music. This study examines the CM initiatives of La Junta, in Santurce (Plena), Taller Tambuyé in Rio Piedras (Bomba), and Decimanía (Música Jíbara), an initiative that stems from the municipality of Hatillo. In terms of procedure, 45–60-minute semi-structured interviews were conducted with organizers and administrators of the CM initiatives to gain insight into the educational philosophy of each project. Following this, a second series of 45–60-minute semi-structured interviews were undertaken with CM educators to collect data on their musical development, teaching practices, and relationship with learners. Subsequently, four weeks were spent observing/participating in each of the three CM initiatives. In addition to participant observations in these projects, five CM learners from each locale were recruited for two one-on-one semi-structured interviews at the beginning and end of the data collection period. The initial interview centered on the participants’ rationale for joining the CM initiative whereas the exit interview focused on participants’ experience within it. Alumni from each of the CM initiatives partook in 45–60-minute semi-structured interviews to investigate their understanding of what it means to be a member of each musical community. Finally, observations and documentation of additional activities hosted/promoted by each initiative, such as festivals, concerts, social gatherings, and workshops, were undertaken. These three initiatives were chosen because of their robust and dynamic practices in fostering the musical expressions of Puerto Rico. Data collection consisted of participant observation, narrative inquiry, historical research, philosophical inquiry, and semi-structured interviews. Data analysis for this research involved relying on theoretical propositions, which entails comparing the results—from each case and as a collective— to the arguments that led to the basis of the research (e.g., literature review, research questions, hypothesis). Comparisons to the theoretical propositions were made through pattern matching, which requires comparing predicted patterns from the literature review to findings from each case. Said process led to the development of an analytic outlook of each CM case and a cross-case synthesis. The purpose of employing said data analysis methodology is to present robust findings about CM practices in Puerto Rico and elucidate similarities and differences between the cases that comprise this research and the relevant literature. Furthermore, through the use of Sound Links’ Nine Domains of Community Music, comparisons to other community projects are made in order to point out parallels and highlight particularities in Puerto Rico.

Keywords: community music, Puerto Rico, music learning, traditional music

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4011 Lattice Dynamics of (ND4Br)x(KBr)1-x Mixed Crystals

Authors: Alpana Tiwari, N. K. Gaur

Abstract:

We have incorporated the translational rotational (TR) coupling effects in the framework of three body force shell model (TSM) to develop an extended TSM (ETSM). The dynamical matrix of ETSM has been applied to compute the phonon frequencies of orientationally disordered mixed crystal (ND4Br)x(KBr)1-x in (q00), (qq0) and (qqq) symmetry directions for compositions 0.10≤x≤0.50 at T=300K.These frequencies are plotted as a function of wave vector k. An unusual acoustic mode softening is found along symmetry directions (q00) and (qq0) as a result of translation-rotation coupling.

Keywords: orientational glass, phonons, TR-coupling, lattice dynamics

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4010 Studies on Organic and Inorganic Micro/Nano Particle Reinforced Epoxy Composites

Authors: Daniel Karthik, Vijay Baheti, Jiri Militky, Sundaramurthy Palanisamy

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Fibre based nano particles are presently considered as one of the potential filler materials for the improvement of mechanical and physical properties of polymer composites. Due to high matrix-filler interfacial area there will be uniform and homogeneous dispersion of nanoparticles. In micro/nano filler reinforced composites, resin material is usually tailored by organic or inorganic nanoparticles to have improved matrix properties. The objective of this study was to compare the potential of reinforcement of different organic and inorganic micro/nano fillers in epoxy composites. Industrial and agricultural waste of fibres like Agave Americana, cornhusk, jute, basalt, carbon, glass and fly ash was utilized to prepare micro/nano particles. Micro/nano particles were obtained using high energy planetary ball milling process in dry condition. Milling time and ball size were kept constant throughout the ball milling process. Composites were fabricated by hand lay method. Particle loading was kept constant to 3% wt. for all composites. In present study, loading of fillers was selected as 3 wt. % for all composites. Dynamic mechanical properties of the nanocomposite films were performed in three-point bending mode with gauge length and sample width of 50 mm and 10 mm respectively. The samples were subjected to an oscillating frequency of 1 Hz, 5 Hz and 10 Hz and 100 % oscillating amplitude in the temperature ranges of 30°C to 150°C at the heating rate of 3°C/min. Damping was found to be higher with the jute composites. Amongst organic fillers lowest damping factor was observed with Agave Americana particles, this means that Agave americana fibre particles have betters interface adhesion with epoxy resin. Basalt, fly ash and glass particles have almost similar damping factors confirming better interface adhesion with epoxy.

Keywords: ball milling, damping factor, matrix-filler interface, particle reinforcements

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4009 The Effect of Discontinued Water Spray Cooling on the Heat Transfer Coefficient

Authors: J. Hrabovský, M. Chabičovský, J. Horský

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Water spray cooling is a technique typically used in heat treatment and other metallurgical processes where controlled temperature regimes are required. Water spray cooling is used in static (without movement) or dynamic (with movement of the steel plate) regimes. The static regime is notable for the fixed position of the hot steel plate and fixed spray nozzle. This regime is typical for quenching systems focused on heat treatment of the steel plate. The second application of spray cooling is the dynamic regime. The dynamic regime is notable for its static section cooling system and moving steel plate. This regime is used in rolling and finishing mills. The fixed position of cooling sections with nozzles and the movement of the steel plate produce nonhomogeneous water distribution on the steel plate. The length of cooling sections and placement of water nozzles in combination with the nonhomogeneity of water distribution leads to discontinued or interrupted cooling conditions. The impact of static and dynamic regimes on cooling intensity and the heat transfer coefficient during the cooling process of steel plates is an important issue. Heat treatment of steel is accompanied by oxide scale growth. The oxide scale layers can significantly modify the cooling properties and intensity during the cooling. The combination of the static and dynamic (section) regimes with the variable thickness of the oxide scale layer on the steel surface impact the final cooling intensity. The study of the influence of the oxide scale layers with different cooling regimes was carried out using experimental measurements and numerical analysis. The experimental measurements compared both types of cooling regimes and the cooling of scale-free surfaces and oxidized surfaces. A numerical analysis was prepared to simulate the cooling process with different conditions of the section and samples with different oxide scale layers.

Keywords: heat transfer coefficient, numerical analysis, oxide layer, spray cooling

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4008 Impact of Television Advertisement on Children Behaviour : A Qualitative Research in India

Authors: Sarbjit Singh, Amit Kumar Lal

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In India there is no governing body to control advertisement apart from ASCI due to which most of the companies are targeting children in their advertisements that have a negative impact on their behaviour. The main purpose of this research paper is to find out the impact of the television advertisement on the behaviour of the children as observed and reported by parents. The exploratory research design is adopted by using in-depth interviews with 20 parents in various cities of Punjab on the basis semi-structured interviews a self-administered structured Questionnaire was developed for data collection. Exploratory factor analysis using varimax rotation is used to analyse the data from 100 parents from the conjoint cities of Punjab. (Jalandhar, Amritsar and Ludhiana) The finding suggests that children demand those products which are more advertised. Parents believe that television advertisements are affecting the study of their children. Moreover, the children are becoming more violent, stubborn and rebellious. They try to start copying from the advertisements and indulge in bad habits. Children demand, nag and pester their parents to purchase the advertised product. This research paper would help advertisers to understand children behaviour towards advertisements and more over what should be done to control the negative impact of advertisement on children. Advertisers can also understand the parental perception towards advertisement.

Keywords: advertisement, consumer behaviour, children perception, teen marketing

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4007 Formation of Volatile Iodine from Cesium Iodide Aerosols: A DFT Study

Authors: Houssam Hijazi, Laurent Cantrel, Jean-François Paul

Abstract:

Periodic DFT calculations were performed to study the chemistry of CsI particles and the possible release of volatile iodine from CsI surfaces for nuclear safety interest. The results show that water adsorbs at low temperature associatively on the (011) surface of CsI, while water desorbs at higher temperatures. On the other hand, removing iodine species from the surface requires oxidizing the surface one time for each removed iodide atom. The activation energy of removing I2 from the surface in the presence of two OH is 1,2 eV.

Keywords: aerosols, CSI, reactivity, DFT, water adsorption

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4006 A Review of Benefit-Risk Assessment over the Product Lifecycle

Authors: M. Miljkovic, A. Urakpo, M. Simic-Koumoutsaris

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Benefit-risk assessment (BRA) is a valuable tool that takes place in multiple stages during a medicine's lifecycle, and this assessment can be conducted in a variety of ways. The aim was to summarize current BRA methods used during approval decisions and in post-approval settings and to see possible future directions. Relevant reviews, recommendations, and guidelines published in medical literature and through regulatory agencies over the past five years have been examined. BRA implies the review of two dimensions: the dimension of benefits (determined mainly by the therapeutic efficacy) and the dimension of risks (comprises the safety profile of a drug). Regulators, industry, and academia have developed various approaches, ranging from descriptive textual (qualitative) to decision-analytic (quantitative) models, to facilitate the BRA of medicines during the product lifecycle (from Phase I trials, to authorization procedure, post-marketing surveillance and health technology assessment for inclusion in public formularies). These approaches can be classified into the following categories: stepwise structured approaches (frameworks); measures for benefits and risks that are usually endpoint specific (metrics), simulation techniques and meta-analysis (estimation techniques), and utility survey techniques to elicit stakeholders’ preferences (utilities). All these approaches share the following two common goals: to assist this analysis and to improve the communication of decisions, but each is subject to its own specific strengths and limitations. Before using any method, its utility, complexity, the extent to which it is established, and the ease of results interpretation should be considered. Despite widespread and long-time use, BRA is subject to debate, suffers from a number of limitations, and currently is still under development. The use of formal, systematic structured approaches to BRA for regulatory decision-making and quantitative methods to support BRA during the product lifecycle is a standard practice in medicine that is subject to continuous improvement and modernization, not only in methodology but also in cooperation between organizations.

Keywords: benefit-risk assessment, benefit-risk profile, product lifecycle, quantitative methods, structured approaches

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4005 Investigation of External Pressure Coefficients on Large Antenna Parabolic Reflector Using Computational Fluid Dynamics

Authors: Varun K, Pramod B. Balareddy

Abstract:

Estimation of wind forces plays a significant role in the in the design of large antenna parabolic reflectors. Reflector surface accuracies are very sensitive to the gain of the antenna system at higher frequencies. Hence accurate estimation of wind forces becomes important, which is primary input for design and analysis of the reflector system. In the present work, numerical simulation of wind flow using Computational Fluid Dynamics (CFD) software is used to investigate the external pressure coefficients. An extensive comparative study has been made between the CFD results and the published wind tunnel data for different wind angle of attacks (α) acting over concave to convex surfaces respectively. Flow simulations using CFD are carried out to estimate the coefficients of Drag, Lift and Moment for the parabolic reflector. Coefficients of pressures (Cp) over the front and the rear face of the reflector are extracted over surface of the reflector to study the net pressure variations. These resultant pressure variations are compared with the published wind tunnel data for different angle of attacks. It was observed from the CFD simulations, both convex and concave face of reflector system experience a band of pressure variations for the positive and negative angle of attacks respectively. In the published wind tunnel data, Pressure variations over convex surfaces are assumed to be uniform and vice versa. Chordwise and spanwise pressure variations were calculated and compared with the published experimental data. In the present work, it was observed that the maximum pressure coefficients for α ranging from +30° to -90° and α=+90° was lower. For α ranging from +45° to +75°, maximum pressure coefficients were higher as compared to wind tunnel data. This variation is due to non-uniform pressure distribution observed over front and back faces of reflector. Variations in Cd, Cl and Cm over α=+90° to α=-90° was in close resemblance with the experimental data.

Keywords: angle of attack, drag coefficient, lift coefficient, pressure coefficient

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4004 Study of the Morphological and Optical Properties of Nanometric NiO

Authors: Nassima Hamzaoui, Mostefa Ghamnia

Abstract:

Nanoscale thin films of pure and Mn-doped Nickel oxide (NiO) were prepared by dissolving nickel chloride hexahydrate (NiCl2, 6H2O) and manganese chloride tetrahydrate (MnCl2,4H2O) under experimental conditions. The resulting solution was stirred at room temperature for 30 OC minutes in order to obtain homogeneity. The solution was sprayed onto heated glass substrates. The films obtained were characterized by X-ray diffraction to verify crystallinity. Atomic force microscopy (AFM) reveals surface topographical structure. UV-visible spectroscopy shows good transparency of the NiO layers.

Keywords: films, NiO, AFM, X-ray diffraction

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4003 Effects of Free-Hanging Horizontal Sound Absorbers on the Cooling Performance of Thermally Activated Building Systems

Authors: L. Marcos Domínguez, Nils Rage, Ongun B. Kazanci, Bjarne W. Olesen

Abstract:

Thermally Activated Building Systems (TABS) have proven to be an energy-efficient solution to provide buildings with an optimal indoor thermal environment. This solution uses the structure of the building to store heat, reduce the peak loads, and decrease the primary energy demand. TABS require the heated or cooled surfaces to be as exposed as possible to the indoor space, but exposing the bare concrete surfaces has a diminishing effect on the acoustic qualities of the spaces in a building. Acoustic solutions capable of providing optimal acoustic comfort and allowing the heat exchange between the TABS and the room are desirable. In this study, the effects of free-hanging units on the cooling performance of TABS and the occupants’ thermal comfort was measured in a full-scale TABS laboratory. Investigations demonstrate that the use of free-hanging sound absorbers are compatible with the performance of TABS and the occupant’s thermal comfort, but an appropriate acoustic design is needed to find the most suitable solution for each case. The results show a reduction of 11% of the cooling performance of the TABS when 43% of the ceiling area is covered with free-hanging horizontal sound absorbers, of 23% for 60% ceiling coverage ratio and of 36% for 80% coverage. Measurements in actual buildings showed an increase of the room operative temperature of 0.3 K when 50% of the ceiling surface is covered with horizontal panels and of 0.8 to 1 K for a 70% coverage ratio. According to numerical simulations using a new TRNSYS Type, the use of comfort ventilation has a considerable influence on the thermal conditions in the room; if the ventilation is removed, then the operative temperature increases by 1.8 K for a 60%-covered ceiling.

Keywords: acoustic comfort, concrete core activation, full-scale measurements, thermally activated building systems, TRNSys

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4002 Reverse Engineering of a Secondary Structure of a Helicopter: A Study Case

Authors: Jose Daniel Giraldo Arias, Camilo Rojas Gomez, David Villegas Delgado, Gullermo Idarraga Alarcon, Juan Meza Meza

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The reverse engineering processes are widely used in the industry with the main goal to determine the materials and the manufacture used to produce a component. There are a lot of characterization techniques and computational tools that are used in order to get this information. A study case of a reverse engineering applied to a secondary sandwich- hybrid type structure used in a helicopter is presented. The methodology used consists of five main steps, which can be applied to any other similar component: Collect information about the service conditions of the part, disassembly and dimensional characterization, functional characterization, material properties characterization and manufacturing processes characterization, allowing to obtain all the supports of the traceability of the materials and processes of the aeronautical products that ensure their airworthiness. A detailed explanation of each step is covered. Criticality and comprehend the functionalities of each part, information of the state of the art and information obtained from interviews with the technical groups of the helicopter’s operators were analyzed,3D optical scanning technique, standard and advanced materials characterization techniques and finite element simulation allow to obtain all the characteristics of the materials used in the manufacture of the component. It was found that most of the materials are quite common in the aeronautical industry, including Kevlar, carbon, and glass fibers, aluminum honeycomb core, epoxy resin and epoxy adhesive. The stacking sequence and volumetric fiber fraction are a critical issue for the mechanical behavior; a digestion acid method was used for this purpose. This also helps in the determination of the manufacture technique which for this case was Vacuum Bagging. Samples of the material were manufactured and submitted to mechanical and environmental tests. These results were compared with those obtained during reverse engineering, which allows concluding that the materials and manufacture were correctly determined. Tooling for the manufacture was designed and manufactured according to the geometry and manufacture process requisites. The part was manufactured and the mechanical, and environmental tests required were also performed. Finally, a geometric characterization and non-destructive techniques allow verifying the quality of the part.

Keywords: reverse engineering, sandwich-structured composite parts, helicopter, mechanical properties, prototype

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4001 Barriers Facing the Implementation of Lean Manufacturing in Libyan Manufacturing Companies

Authors: Mohamed Abduelmula, Martin Birkett, Chris Connor

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Lean Manufacturing has developed from being a set of tools and methods to becoming a management philosophy which can be used to remove or reduce waste in manufacturing processes and so enhance the operational productivity of an enterprise. Several enterprises around the world have applied the lean manufacturing system and gained great improvements. This paper investigates the barriers and obstacles that face Libyan manufacturing companies to implement lean manufacturing. A mixed-method approach is suggested, starting with conducting a questionnaire to get quantitative data then using this to develop semi-structured interviews to collect qualitative data. The findings of the questionnaire results and how these can be used further develop the semi-structured interviews are then discussed. The survey was distributed to 65 manufacturing companies in Libya, and a response rate of 64.6% was obtained. The results showed that these are five main barriers to implementing lean in Libya, namely organizational culture, skills and expertise, and training program, financial capability, top management, and communication. These barriers were also identified from the literature as being significant obstacles to implementing Lean in other countries industries. Having an understanding of the difficulties that face the implementation of lean manufacturing systems, as a new and modern system and using this to develop a suitable framework will help to improve the manufacturing sector in Libya.

Keywords: lean manufacturing, barriers, questionnaire, Libyan manufacturing companies

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4000 Leveraging Business to Business Collaborations to Optimize Reverse Haul Logistics

Authors: Pallav Singh, Rajesh Yabaji, Rajesh Dhir, Chanakya Hridaya

Abstract:

Supply Chain Costs for the Indian Industries have been on an exponential trend due to steep inflation on fundamental cost factors – Fuel, Labour, Rents. In this changing context organizations have been focusing on adopting multiple approaches to keep logistics costs under control to protect the profit margins. The lever of ‘Business to Business (B2B) collaboration’ can be used by organizations to garner higher value. Given the context of Indian Logistics Industry the penetration of B2B Collaboration initiatives have been limited. This paper outlines a structured framework for adoption of B2B collaboration through discussion of a successful initiative between ITC’s Leaf Tobacco Business and a leading Indian Media House. Multiple barriers to such a collaborative process exist which need to be addressed through comprehensive structured approaches. This paper outlines a generic framework approach to B2B collaboration for the Indian Logistics Space, outlining the guidelines for arriving at potential opportunities, identification of collaborators, effective tie-up process, design of operations and sustenance factors. The generic methods outlined can be used in any other industry and also builds a foundation for further research on many topics.

Keywords: business to business collaboration, reverse haul logistics, transportation cost optimization, exports logistics

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3999 Influence of Cobalt Incorporation on the Structure and Properties of SOL-Gel Derived Mesoporous Bioglass Nanoparticles

Authors: Ahmed El-Fiqi, Hae-Won Kim

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Incorporation of therapeutic elements such as Sr, Cu and Co into bioglass structure and their release as ions is considered as one of the promising approaches to enhance cellular responses, e.g., osteogenesis and angiogenesis. Here, cobalt as angiogenesis promoter has been incorporated (at 0, 1 and 4 mol%) into sol-gel derived calcium silicate mesoporous bioglass nanoparticles. The composition and structure of cobalt-free (CFN) and cobalt-doped (CDN) mesoporous bioglass nanoparticles have been analyzed by X-ray fluorescence (XRF), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier-Transform Infra-red spectroscopy (FT-IR). The physicochemical properties of CFN and CDN have been investigated using high-resolution transmission electron microscopy (HR-TEM), Selected area electron diffraction (SAED), and Energy-dispersive X-ray (EDX). Furthermore, the textural properties, including specific surface area, pore-volume, and pore size, have been analyzed from N²⁻sorption analyses. Surface charges of CFN and CDN were also determined from surface zeta potential measurements. The release of ions, including Co²⁺, Ca²⁺, and SiO₄⁴⁻ has been analyzed using inductively coupled plasma atomic emission spectrometry (ICP-AES). Loading and release of diclofenac as an anti-inflammatory drug model were explored in vitro using Ultraviolet-visible spectroscopy (UV-Vis). XRD results ensured the amorphous state of CFN and CDN whereas, XRF further confirmed that their chemical compositions are very close to the designed compositions. HR-TEM analyses unveiled nanoparticles with spherical morphologies, highly mesoporous textures, and sizes in the range of 90 - 100 nm. Moreover, N²⁻ sorption analyses revealed that the nanoparticles have pores with sizes of 3.2 - 2.6 nm, pore volumes of 0.41 - 0.35 cc/g and highly surface areas in the range of 716 - 830 m²/g. High-resolution XPS analysis of Co 2p core level provided structural information about Co atomic environment and it confirmed the electronic state of Co in the glass matrix. ICP-AES analysis showed the release of therapeutic doses of Co²⁺ ions from 4% CDN up to 100 ppm within 14 days. Finally, diclofenac loading and release have ensured the drug/ion co-delivery capability of 4% CDN.

Keywords: mesoporous bioactive glass, nanoparticles, cobalt ions, release

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3998 Conceptual Design of Suction Cup Lifting System

Authors: Mohammed Aijaz

Abstract:

In industries, to transfer fragile materials like glasses, a holding, lifting, and manipulation system are required. In this report, we designed and analysed a suction cup holding, lifting, and manipulation system that is attached to a head plate and must be able to grip/hold securely, the largest glass panel with 3m x 2.5m x 20mm thick with a mass of 115 kg. The system is able to rotate the panel through 180 degrees in the X, Y, and Z axis in any direction from the outer reach of the robotic arm. The structural analysis is performed to verify the structural strength of the suction cup’s head plate system.

Keywords: designing, mechanical, engineering, suction

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3997 Healthcare Big Data Analytics Using Hadoop

Authors: Chellammal Surianarayanan

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Healthcare industry is generating large amounts of data driven by various needs such as record keeping, physician’s prescription, medical imaging, sensor data, Electronic Patient Record(EPR), laboratory, pharmacy, etc. Healthcare data is so big and complex that they cannot be managed by conventional hardware and software. The complexity of healthcare big data arises from large volume of data, the velocity with which the data is accumulated and different varieties such as structured, semi-structured and unstructured nature of data. Despite the complexity of big data, if the trends and patterns that exist within the big data are uncovered and analyzed, higher quality healthcare at lower cost can be provided. Hadoop is an open source software framework for distributed processing of large data sets across clusters of commodity hardware using a simple programming model. The core components of Hadoop include Hadoop Distributed File System which offers way to store large amount of data across multiple machines and MapReduce which offers way to process large data sets with a parallel, distributed algorithm on a cluster. Hadoop ecosystem also includes various other tools such as Hive (a SQL-like query language), Pig (a higher level query language for MapReduce), Hbase(a columnar data store), etc. In this paper an analysis has been done as how healthcare big data can be processed and analyzed using Hadoop ecosystem.

Keywords: big data analytics, Hadoop, healthcare data, towards quality healthcare

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3996 Cupric Oxide Thin Films for Optoelectronic Application

Authors: Sanjay Kumar, Dinesh Pathak, Sudhir Saralch

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Copper oxide is a semiconductor that has been studied for several reasons such as the natural abundance of starting material copper (Cu); the easiness of production by Cu oxidation; their non-toxic nature and the reasonably good electrical and optical properties. Copper oxide is well-known as cuprite oxide. The cuprite is p-type semiconductors having band gap energy of 1.21 to 1.51 eV. As a p-type semiconductor, conduction arises from the presence of holes in the valence band (VB) due to doping/annealing. CuO is attractive as a selective solar absorber since it has high solar absorbency and a low thermal emittance. CuO is very promising candidate for solar cell applications as it is a suitable material for photovoltaic energy conversion. It has been demonstrated that the dip technique can be used to deposit CuO films in a simple manner using metallic chlorides (CuCl₂.2H₂O) as a starting material. Copper oxide films are prepared using a methanolic solution of cupric chloride (CuCl₂.2H₂O) at three baking temperatures. We made three samples, after heating which converts to black colour. XRD data confirm that the films are of CuO phases at a particular temperature. The optical band gap of the CuO films calculated from optical absorption measurements is 1.90 eV which is quite comparable to the reported value. Dip technique is a very simple and low-cost method, which requires no sophisticated specialized setup. Coating of the substrate with a large surface area can be easily obtained by this technique compared to that in physical evaporation techniques and spray pyrolysis. Another advantage of the dip technique is that it is very easy to coat both sides of the substrate instead of only one and to deposit otherwise inaccessible surfaces. This method is well suited for applying coating on the inner and outer surfaces of tubes of various diameters and shapes. The main advantage of the dip coating method lies in the fact that it is possible to deposit a variety of layers having good homogeneity and mechanical and chemical stability with a very simple setup. In this paper, the CuO thin films preparation by dip coating method and their characterization will be presented.

Keywords: absorber material, cupric oxide, dip coating, thin film

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3995 A Feminist Historical Institutional Approach and Gender Participation in Queensland Politics

Authors: Liz van Acker, Linda Colley

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Political processes are shaped by the gendered culture of parliaments. This paper examines how the institution of parliament has been affected by the changing number of women in politics. In order to understand how and why gender change occurs, the paper employs a feminist historical institutionalism approach. It argues that while it is difficult to change the gendered nature of political institutions, it is possible, from a gender perspective, to understand the processes of change both formally and informally. Increasing women’s representation has been a slow process which has not occurred without political struggles. A broadly defined ‘feminist historical institutionalism’ has critiqued existing approaches to institutions and combined historical institutional analysis with tools of gender to enhance our understanding of institutional processes and change. The paper examines the gendered rules, norms, and practices that influence institutional design choices and processes. Institutions such as Parliament often are able to adjust to women’s entry and absorb them without too much interruption. Exploring the hidden aspects to informal institutions involves identifying unspoken and accepted norms that may guide decision-making – exposing and questioning the gender status quo. This paper examines the representation of women in the Queensland Parliament, Australia. It places the Queensland experience in historical context, as well as in the national and international context. The study is interesting, given that its gender representation has rocketed from one of the worst performing states in 2012 to one of the best performing in 2015 with further improvements in 2017. The state currently has a re-elected female Premier, a female Deputy Premier and a female-dominated cabinet – in fact, Queensland was the first ministry in Australia to have a majority of women in its Cabinet. However, it is unnecessary to dig far below these headlines to see that this is uncharacteristic of its history: progress towards this current position has been slow and patchy. The paper finds that matters such as the glass ceiling and the use of quotas explain women’s recent success in Queensland politics.

Keywords: feminist historical institutional approach, glass ceiling, quotas, women’s participation in politics

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3994 Aerodynamic Analysis of Vehicles

Authors: E. T. L. Cöuras Ford, V. A. C. Vale, J. U. L. Mendes

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Two of the objective principal in the study of the aerodynamics of vehicles are the safety and the acting. Those objectives can be reached through the development of devices modify the drainage of air about of the vehicle and also through alterations in the way of the external surfaces. The front lowest profile of the vehicle, for instance, has great influence on the coefficient of aerodynamic penetration (Cx) and later on great part of the pressure distribution along the surface of the vehicle. The objective of this work was of analyzing the aerodynamic behavior that it happens on some types the trucks of vehicles, based on experimentation in aerodynamic tunnel, seeking to determine the aerodynamic efficiency of each one of them.

Keywords: aerodynamic, vehicles, wind tunnel, safety, acting

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3993 An Empirical Study of Students’ Learning Attitude, Problem-solving Skills and Learning Engagement in an Online Internship Course During Pandemic

Authors: PB Venkataraman

Abstract:

Most of the real-life problems are ill-structured. They do not have a single solution but many competing solutions. The solution paths are non-linear and ambiguous, and the problem definition itself is many times a challenge. Students of professional education learn to solve such problems through internships. The current pandemic situation has constrained on-site internship opportunities; thus the students have no option but to pursue this learning online. This research assessed the learning gain of four undergraduate students in engineering as they undertook an online internship in an organisation over a period of eight weeks. A clinical interview at the end of the internship provided the primary data to assess the team’s problem-solving skills using a tested rubric. In addition to this, change in their learning attitudes were assessed through a pre-post study using a repurposed CLASS instrument for Electrical Engineering. Analysis of CLASS data indicated a shift in the sophistication of their learning attitude. A learning engagement survey adopting a 6-point Likert scale showed active participation and motivation in learning. We hope this new research will stimulate educators to exploit online internships even beyond the time of pandemic as more and more business operations are transforming into virtual.

Keywords: ill-structured problems, learning attitudes, internship, assessment, student engagement

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3992 Developing Structured Sizing Systems for Manufacturing Ready-Made Garments of Indian Females Using Decision Tree-Based Data Mining

Authors: Hina Kausher, Sangita Srivastava

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In India, there is a lack of standard, systematic sizing approach for producing readymade garments. Garments manufacturing companies use their own created size tables by modifying international sizing charts of ready-made garments. The purpose of this study is to tabulate the anthropometric data which covers the variety of figure proportions in both height and girth. 3,000 data has been collected by an anthropometric survey undertaken over females between the ages of 16 to 80 years from some states of India to produce the sizing system suitable for clothing manufacture and retailing. This data is used for the statistical analysis of body measurements, the formulation of sizing systems and body measurements tables. Factor analysis technique is used to filter the control body dimensions from a large number of variables. Decision tree-based data mining is used to cluster the data. The standard and structured sizing system can facilitate pattern grading and garment production. Moreover, it can exceed buying ratios and upgrade size allocations to retail segments.

Keywords: anthropometric data, data mining, decision tree, garments manufacturing, sizing systems, ready-made garments

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3991 3D Codes for Unsteady Interaction Problems of Continuous Mechanics in Euler Variables

Authors: M. Abuziarov

Abstract:

The designed complex is intended for the numerical simulation of fast dynamic processes of interaction of heterogeneous environments susceptible to the significant formability. The main challenges in solving such problems are associated with the construction of the numerical meshes. Currently, there are two basic approaches to solve this problem. One is using of Lagrangian or Lagrangian Eulerian grid associated with the boundaries of media and the second is associated with the fixed Eulerian mesh, boundary cells of which cut boundaries of the environment medium and requires the calculation of these cut volumes. Both approaches require the complex grid generators and significant time for preparing the code’s data for simulation. In this codes these problems are solved using two grids, regular fixed and mobile local Euler Lagrange - Eulerian (ALE approach) accompanying the contact and free boundaries, the surfaces of shock waves and phase transitions, and other possible features of solutions, with mutual interpolation of integrated parameters. For modeling of both liquids and gases, and deformable solids the Godunov scheme of increased accuracy is used in Lagrangian - Eulerian variables, the same for the Euler equations and for the Euler- Cauchy, describing the deformation of the solid. The increased accuracy of the scheme is achieved by using 3D spatial time dependent solution of the discontinuity problem (3D space time dependent Riemann's Problem solver). The same solution is used to calculate the interaction at the liquid-solid surface (Fluid Structure Interaction problem). The codes does not require complex 3D mesh generators, only the surfaces of the calculating objects as the STL files created by means of engineering graphics are given by the user, which greatly simplifies the preparing the task and makes it convenient to use directly by the designer at the design stage. The results of the test solutions and applications related to the generation and extension of the detonation and shock waves, loading the constructions are presented.

Keywords: fluid structure interaction, Riemann's solver, Euler variables, 3D codes

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3990 Controller Design for Highly Maneuverable Aircraft Technology Using Structured Singular Value and Direct Search Method

Authors: Marek Dlapa

Abstract:

The algebraic approach is applied to the control of the HiMAT (Highly Maneuverable Aircraft Technology). The objective is to find a robust controller which guarantees robust stability and decoupled control of longitudinal model of a scaled remotely controlled vehicle version of the advanced fighter HiMAT. Control design is performed by decoupling the nominal MIMO (multi-input multi-output) system into two identical SISO (single-input single-output) plants which are approximated by a 4th order transfer function. The algebraic approach is then used for pole placement design, and the nominal closed-loop poles are tuned so that the peak of the µ-function is minimal. As an optimization tool, evolutionary algorithm Differential Migration is used in order to overcome the multimodality of the cost function yielding simple controller with decoupling for nominal plant which is compared with the D-K iteration through simulations of standard longitudinal manoeuvres documenting decoupled control obtained from algebraic approach for nominal plant as well as worst case perturbation.

Keywords: algebraic approach, evolutionary computation, genetic algorithms, HiMAT, robust control, structured singular value

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3989 Studies on Radio Frequency Sputtered Copper Zinc Tin Sulphide Absorber Layers for Thin Film Solar Cells

Authors: G. Balaji, R. Balasundaraprabhu, S. Prasanna, M. D. Kannan, K. Sivakumaran, David Mcilroy

Abstract:

Copper Zin tin sulphide (Cu2ZnSnS4 or CZTS) is found to be better alternative to Copper Indium gallium diselenide as absorber layers in thin film based solar cells due to the utilisation of earth-abundant materials in the midst of lower toxicity. In the present study, Cu2ZnSnS4 thin films were prepared on soda lime glass using (CuS, ZnS, SnS) targets and were deposited by three different stacking orders, using RF Magnetron sputtering. The substrate temperature was fixed at 300 °C during the depositions. CZTS thin films were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and UV-Vis-NIR spectroscopy. All the samples exhibited X-ray peaks pertaining to (112) kesterite phase of CZTS, along with the presence of a predominant wurtzite CZTS phase. X-ray photoelectron spectroscopy revealed the presence of all the elements in all the samples. The change in stacking order clearly shows that it affects the structural and phase properties of the films. Relative atomic concentrations of Zn, Cu, Sn and S, which are determined by high-resolution XPS core level spectra integrated peak areas revealed that the CZTS films exhibit inhomogeneity in both stoichiometry and elemental composition. Raman spectroscopy studies on the film showed the presence of CZTS phase. The energy band gap of the CZTS thin films was found to be in the range of 1.5 eV to 1.6 eV. The films were then annealed at 450 °C for 5 hrs and it was found that the predominant nature of the X-ray peaks has transformed from Wurtzite to Kesterite phase which is highly desirable for absorber layers in thin film solar cells. The optimized CZTS layer was used as an absorber layer in thin film solar cells. ZnS and CdS were used as buffer layers which in turn prepared by Hot wall epitaxy technique. Gallium doped Zinc oxide was used as a transparent conducting oxide. The solar cell structure Glass/Mo/CZTS/CdS or ZnS/GZO has been fabricated, and solar cell parameters were measured.

Keywords: earth-abundant, Kesterite, RF sputtering, thin film solar cells

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3988 Electroactive Fluorene-Based Polymer Films Obtained by Electropolymerization

Authors: Mariana-Dana Damaceanu

Abstract:

Electrochemical oxidation is one of the most convenient ways to obtain conjugated polymer films as polypyrrole, polyaniline, polythiophene or polycarbazole. The research in the field has been mainly directed to the study of electrical conduction properties of the materials obtained by electropolymerization, often the main reason being their use as electroconducting electrodes, and very little attention has been paid to the morphological and optical quality of the films electrodeposited on flat surfaces. Electropolymerization of the monomer solution was scarcely used in the past to manufacture polymer-based light-emitting diodes (PLED), most probably due to the difficulty of obtaining defectless polymer films with good mechanical and optical properties, or conductive polymers with well controlled molecular weights. Here we report our attempts in using electrochemical deposition as appropriate method for preparing ultrathin films of fluorene-based polymers for PLED applications. The properties of these films were evaluated in terms of structural morphology, optical properties, and electrochemical conduction. Thus, electropolymerization of 4,4'-(9-fluorenylidene)-dianiline was performed in dichloromethane solution, at a concentration of 10-2 M, using 0.1 M tetrabutylammonium tetrafluoroborate as electrolyte salt. The potential was scanned between 0 and 1.3 V on the one hand, and 0 - 2 V on the other hand, when polymer films with different structures and properties were obtained. Indium tin oxide-coated glass substrate of different size was used as working electrode, platinum wire as counter electrode and calomel electrode as reference. For each potential range 100 cycles were recorded at a scan rate of 100 mV/s. The film obtained in the potential range from 0 to 1.3 V, namely poly(FDA-NH), is visible to the naked eye, being light brown, transparent and fluorescent, and displays an amorphous morphology. Instead, the electrogrowth poly(FDA) film in the potential range of 0 - 2 V is yellowish-brown and opaque, presenting a self-assembled structure in aggregates of irregular shape and size. The polymers structure was identified by FTIR spectroscopy, which shows the presence of broad bands specific to a polymer, the band centered at approx. 3443 cm-1 being ascribed to the secondary amine. The two polymer films display two absorption maxima, at 434-436 nm assigned to π-π* transitions of polymers, and another at 832 and 880 nm assigned to polaron transitions. The fluorescence spectra indicated the presence of emission bands in the blue domain, with two peaks at 422 and 488 nm for poly (FDA-NH), and four narrow peaks at 422, 447, 460 and 484 nm for poly(FDA), peaks originating from fluorene-containing segments of varying degrees of conjugation. Poly(FDA-NH) exhibited two oxidation peaks in the anodic region and the HOMO energy value of 5.41 eV, whereas poly(FDA) showed only one oxidation peak and the HOMO level localized at 5.29 eV. The electrochemical data are discussed in close correlation with the proposed chemical structure of the electrogrowth films. Further research will be carried out to study their use and performance in light-emitting devices.

Keywords: electrogrowth polymer films, fluorene, morphology, optical properties

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3987 Contrastive Learning for Unsupervised Object Segmentation in Sequential Images

Authors: Tian Zhang

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Unsupervised object segmentation aims at segmenting objects in sequential images and obtaining the mask of each object without any manual intervention. Unsupervised segmentation remains a challenging task due to the lack of prior knowledge about these objects. Previous methods often require manually specifying the action of each object, which is often difficult to obtain. Instead, this paper does not need action information of objects and automatically learns the actions and relations among objects from the structured environment. To obtain the object segmentation of sequential images, the relationships between objects and images are extracted to infer the action and interaction of objects based on the multi-head attention mechanism. Three types of objects’ relationships in the object segmentation task are proposed: the relationship between objects in the same frame, the relationship between objects in two frames, and the relationship between objects and historical information. Based on these relationships, the proposed model (1) is effective in multiple objects segmentation tasks, (2) just needs images as input, and (3) produces better segmentation results as more relationships are considered. The experimental results on multiple datasets show that this paper’s method achieves state-of-art performance. The quantitative and qualitative analyses of the result are conducted. The proposed method could be easily extended to other similar applications.

Keywords: unsupervised object segmentation, attention mechanism, contrastive learning, structured environment

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3986 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

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3985 Protecting Physicochemical Properties of Black Cumin Seed (Nigella sativa) Oil and Developing Value Added Products

Authors: Zeliha Ustun, Mustafa Ersoz

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In the study, a traditional herbal supplement black cumin seed (Nigella sativa) oil properties has been studied to protect the main quality parameters by a new supplement application. Black cumin seed and its oil is used as a dietary supplement and preferred traditional remedy in Africa, Asia and Middle East for centuries. Now it has been consuming by millions of people in America and Europe as natural supplements and/or phytotherapeutic agents to support immune system, asthma, allergic rinnitis etc. by the scientists’ advices. With the study, it is aimed to prove that soft gelatin capsules are a new and more practical way of usage for Nigella sativa oil that has a longer stability. With the study soft gelatin capsules formulation has been developed to protect cold pressed black cumin seed oil physicochemical properties for a longer period. The product design has been developed in laboratory and implemented in pilot scale soft gelatin capsule manufacturing. Physicochemical properties (peroxide value, free fatty acids, fatty acid composition, refractive index, iodine value, saponification value, unsaponifiable matters) of Nigella sativa oil soft gelatin capsules and Nigella sativa oil in liquid form in amber glass bottles have been compared and followed for 8 months. The main parameters for capsules and liquid form found that for free fatty acids 2.29±0.03, 3.92±0.11 % oleic acid, peroxide 23.11±1.18, 27.85±2.50 meqO2/kg, refractive index at 20 0C 1.4738±0.00, 1.4737±0.00, soap 0 ppm, moisture and volatility 0.32±0.01, 0.36±0.01 %, iodine value 123.00±0.00, 122.00±0.00 wijs, saponification value 196.25±0.46, 194.13±0.35 mg KOH/g and unsaponifiable matter 7.72±0.13, 6.88±0.36 g/kg respectively. The main fatty acids are found that linoleic acid 56.17%, oleic acid 24.64%, palmitic acid 11,94 %. As a result, it is found that cold pressed Nigella sativa oil soft gelatin capsules physicochemical properties are more stable than the Nigella sativa oil stored in glass bottles.

Keywords: black cumin seed (Nigella sativa) oil, cold press, nutritional supplements, soft gelatin capsule

Procedia PDF Downloads 369
3984 Using Optical Character Recognition to Manage the Unstructured Disaster Data into Smart Disaster Management System

Authors: Dong Seop Lee, Byung Sik Kim

Abstract:

In the 4th Industrial Revolution, various intelligent technologies have been developed in many fields. These artificial intelligence technologies are applied in various services, including disaster management. Disaster information management does not just support disaster work, but it is also the foundation of smart disaster management. Furthermore, it gets historical disaster information using artificial intelligence technology. Disaster information is one of important elements of entire disaster cycle. Disaster information management refers to the act of managing and processing electronic data about disaster cycle from its’ occurrence to progress, response, and plan. However, information about status control, response, recovery from natural and social disaster events, etc. is mainly managed in the structured and unstructured form of reports. Those exist as handouts or hard-copies of reports. Such unstructured form of data is often lost or destroyed due to inefficient management. It is necessary to manage unstructured data for disaster information. In this paper, the Optical Character Recognition approach is used to convert handout, hard-copies, images or reports, which is printed or generated by scanners, etc. into electronic documents. Following that, the converted disaster data is organized into the disaster code system as disaster information. Those data are stored in the disaster database system. Gathering and creating disaster information based on Optical Character Recognition for unstructured data is important element as realm of the smart disaster management. In this paper, Korean characters were improved to over 90% character recognition rate by using upgraded OCR. In the case of character recognition, the recognition rate depends on the fonts, size, and special symbols of character. We improved it through the machine learning algorithm. These converted structured data is managed in a standardized disaster information form connected with the disaster code system. The disaster code system is covered that the structured information is stored and retrieve on entire disaster cycle such as historical disaster progress, damages, response, and recovery. The expected effect of this research will be able to apply it to smart disaster management and decision making by combining artificial intelligence technologies and historical big data.

Keywords: disaster information management, unstructured data, optical character recognition, machine learning

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3983 Leadership Lessons from Female Executives in the South African Oil Industry

Authors: Anthea Carol Nefdt

Abstract:

In this article, observations are drawn from a number of interviews conducted with female executives in the South African Oil Industry in 2017. Globally, the oil industry represents one of the most male-dominated organisational structures as well as cultures in the business world. Some of the remarkable women, who hold upper management positions, have not only emerged from the science and finance spheres (equally gendered organisations) but also navigated their way through an aggressive, patriarchal atmosphere of rivalry and competition. We examine various mythology associated with the industry, such as the cowboy myth, the frontier ideology and the queen bee syndrome directed at female executives. One of the themes to emerge from my interviews was the almost unanimous rejection of the ‘glass ceiling’ metaphor favoured by some Feminists. The women of the oil industry rather affirmed a picture of their rise to leadership positions through a strategic labyrinth of challenges and obstacles both in terms of gender and race. This article aims to share the insights of women leaders in a complex industry through both their reflections and a theoretical Feminist lens. The study is located within the South African context and given our historical legacy, it was optimal to use an intersectional approach which would allow issues of race, gender, ethnicity and language to emerge. A qualitative research methodological approach was employed as well as a thematic interpretative analysis to analyse and interpret the data. This research methodology was used precisely because it encourages and acknowledged the experiences women have and places these experiences at the centre of the research. Multiple methods of recruitment of the research participants was utilised. The initial method of recruitment was snowballing sampling, the second method used was purposive sampling. In addition to this, semi-structured interviews gave the participants an opportunity to ask questions, add information and have discussions on issues or aspects of the research area which was of interest to them. One of the key objectives of the study was to investigate if there was a difference in the leadership styles of men and women. Findings show that despite the wealth of literature on the topic, to the contrary some women do not perceive a significant difference in men and women’s leadership style. However other respondents felt that there were some important differences in the experiences of men and women superiors although they hesitated to generalise from these experiences Further findings suggest that although the oil industry provides unique challenges to women as a gendered organization, it also incorporates various progressive initiatives for their advancement.

Keywords: petroleum industry, gender, feminism, leadership

Procedia PDF Downloads 151