Search results for: Padé time stepping
11274 Pre-Cooling Strategies for the Refueling of Hydrogen Cylinders in Vehicular Transport
Authors: C. Hall, J. Ramos, V. Ramasamy
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Hydrocarbon-based fuel vehicles are a major contributor to air pollution due to harmful emissions produced, leading to a demand for cleaner fuel types. A leader in this pursuit is hydrogen, with its application in vehicles producing zero harmful emissions and the only by-product being water. To compete with the performance of conventional vehicles, hydrogen gas must be stored on-board of vehicles in cylinders at high pressures (35–70 MPa) and have a short refueling duration (approximately 3 mins). However, the fast-filling of hydrogen cylinders causes a significant rise in temperature due to the combination of the negative Joule-Thompson effect and the compression of the gas. This can lead to structural failure and therefore, a maximum allowable internal temperature of 85°C has been imposed by the International Standards Organization. The technological solution to tackle the issue of rapid temperature rise during the refueling process is to decrease the temperature of the gas entering the cylinder. Pre-cooling of the gas uses a heat exchanger and requires energy for its operation. Thus, it is imperative to determine the least amount of energy input that is required to lower the gas temperature for cost savings. A validated universal thermodynamic model is used to identify an energy-efficient pre-cooling strategy. The model requires negligible computational time and is applied to previously validated experimental cases to optimize pre-cooling requirements. The pre-cooling characteristics include the location within the refueling timeline and its duration. A constant pressure-ramp rate is imposed to eliminate the effects of rapid changes in mass flow rate. A pre-cooled gas temperature of -40°C is applied, which is the lowest allowable temperature. The heat exchanger is assumed to be ideal with no energy losses. The refueling of the cylinders is modeled with the pre-cooling split in ten percent time intervals. Furthermore, varying burst durations are applied in both the early and late stages of the refueling procedure. The model shows that pre-cooling in the later stages of the refuelling process is more energy-efficient than early pre-cooling. In addition, the efficiency of pre-cooling towards the end of the refueling process is independent of the pressure profile at the inlet. This leads to the hypothesis that pre-cooled gas should be applied as late as possible in the refueling timeline and at very low temperatures. The model had shown a 31% reduction in energy demand whilst achieving the same final gas temperature for a refueling scenario when pre-cooling was applied towards the end of the process. The identification of the most energy-efficient refueling approaches whilst adhering to the safety guidelines is imperative to reducing the operating cost of hydrogen refueling stations. Heat exchangers are energy-intensive and thus, reducing the energy requirement would lead to cost reduction. This investigation shows that pre-cooling should be applied as late as possible and for short durations.Keywords: cylinder, hydrogen, pre-cooling, refueling, thermodynamic model
Procedia PDF Downloads 9611273 Balanced Score Card a Tool to Improve Naac Accreditation – a Case Study in Indian Higher Education
Authors: CA Kishore S. Peshori
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Introduction: India, a country with vast diversity and huge population is going to have largest young population by 2020. Higher education has and will always be the basic requirement for making a developing nation to a developed nation. To improve any system it needs to be bench-marked. There have been various tools for bench-marking the systems. Education is delivered in India by universities which are mainly funded by government. This universities for delivering the education sets up colleges which are again funded mainly by government. Recently however there has also been autonomy given to universities and colleges. Moreover foreign universities are waiting to enter Indian boundaries. With a large number of universities and colleges it has become more and more necessary to measure this institutes for bench-marking. There have been various tools for measuring the institute. In India college assessments have been made compulsory by UGC. Naac has been offically recognised as the accrediation criteria. The Naac criteria has been based on seven criterias namely: 1. Curricular assessments, 2. Teaching learning and evaluation, 3. Research Consultancy and Extension, 4. Infrastructure and learning resources, 5. Student support and progression, 6. Governance leadership and management, 7. Innovation and best practices. The Naac tries to bench mark the institution for identification, sustainability, dissemination and adaption of best practices. It grades the institution according to this seven criteria and the funding of institution is based on these grades. Many of the colleges are struggling to get best of grades but they have not come across a systematic tool to achieve the results. Balanced Scorecard developed by Kaplan has been a successful tool for corporates to develop best of practices so as to increase their financial performance and also retain and increase their customers so as to grow the organization to next level.It is time to test this tool for an educational institute. Methodology: The paper tries to develop a prototype for college based on the secondary data. Once a prototype is developed the researcher based on questionnaire will try to test this tool for successful implementation. The success of this research will depend on its implementation of BSC on an institute and its grading improved due to this successful implementation. Limitation of time is a major constraint in this research as Naac cycle takes minimum 4 years for accreditation and reaccreditation the methodology will limit itself to secondary data and questionnaire to be circulated to colleges along with the prototype model of BSC. Conclusion: BSC is a successful tool for enhancing growth of an organization. Educational institutes are no exception to these. BSC will only have to be realigned to suit the Naac criteria. Once this prototype is developed the success will be tested only on its implementation but this research paper will be the first step towards developing this tool and will also initiate the success by developing a questionnaire and getting and evaluating the responses for moving to the next level of actual implementationKeywords: balanced scorecard, bench marking, Naac, UGC
Procedia PDF Downloads 27211272 Sulfur Removal of Hydrocarbon Fuels Using Oxidative Desulfurization Enhanced by Fenton Process
Authors: Mahsa Ja’fari, Mohammad R. Khosravi-Nikou, Mohsen Motavassel
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A comprehensive development towards the production of ultra-clean fuels as a feed stoke is getting to raise due to the increasing use of diesel fuels and global air pollution. Production of environmental-friendly fuels can be achievable by some limited single methods and most integrated ones. Oxidative desulfurization (ODS) presents vast ranges of technologies possessing suitable characteristics with regard to the Fenton process. Using toluene as a model fuel feed with dibenzothiophene (DBT) as a sulfur compound under various operating conditions is the attempt of this study. The results showed that this oxidative process followed a pseudo-first order kinetics. Removal efficiency of 77.43% is attained under reaction time of 40 minutes with (Fe+2/H2O2) molar ratio of 0.05 in acidic pH environment. In this research, temperature of 50 °C represented the most influential role in proceeding the reaction.Keywords: design of experiment (DOE), dibenzothiophene (DBT), optimization, oxidative desulfurization (ODS)
Procedia PDF Downloads 21711271 Poly(Butadiene-co-Acrylonitrile)-Polyaniline Dodecylbenzenesulfonate [NBR-PAni.DBSA] Blends for Corrosion Inhibition of Carbon Steel
Authors: Kok-Chong Yong
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Poly(butadiene-co-acrylonitrile)-polyaniline Dodecylbenzenesulfonate [NBR-PAni.DBSA] blends with useful electrical conductivity (up to 0.1 S/cm) were prepared and their corrosion inhibiting behaviours for carbon steel were successfully assessed for the first time. The level of compatibility between NBR and PAni.DBSA was enhanced through the introduction of 1.0 wt % hydroquinone. As found from both total immersion and electrochemical corrosion tests, NBR-PAni.DBSA blends with 10.0-30.0 wt% of PAni.DBSA content exhibited the best corrosion inhibiting behaviour for carbon steel, either in acid or artificial brine environment. On the other hand, blends consisting of very low and very high PAni.DBSA contents (i.e. ≤ 5.0 wt % and ≥ 40.0 wt %) showed significantly poorer corrosion inhibiting behaviour for carbon steel.Keywords: conductive rubber, nitrile rubber, polyaniline, carbon steel, corrosion inhibition
Procedia PDF Downloads 46011270 Piracy Killed the Radio Star: A System Archetype Analysis of Digital Music Theft
Authors: Marton Gergely
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Digital experience goods, such as music and video, are readily available and easily accessible through a sundry of illegal mediums. Furthermore, the rate of music theft has been increasing at a seemingly unstoppable rate. Instead of studying the effect of copyright infringement on affected shareholders, this paper aims to examine the overall impact that digital music piracy has on society as a whole. Through a systems dynamics approach, an archetype is built to model the behavior of both legal and illegal music users. Additionally, the effects over time are considered. The conceptual model suggests that if piracy continues to grow at the current pace, industry shareholders will eventually lose the motivation to supply new music. In turn, this tragedy would affect not only the illegal players, but legal consumers as well, by means of a decrease in overall quality of life.Keywords: music piracy, illegal downloading, tragedy of the commons, system archetypes
Procedia PDF Downloads 35711269 The First Record of Pseudogrillotia spratti Campbell and Beveridge, 1993 (Cestoda: Trypanorhyncha) Parasitic in Three Carangid Fishes from Northwest of the Arab Gulf, Iraq
Authors: Khalidah S. Al-Niaeem, Suzan A. Al-Azizz, Fatimah H. Al-Ataby
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The first record of Pseudogrillotia spratti Campbell and Beveridge, 1993 (Cestoda: Trypanorhyncha) was found in body cavity of three species of Carangid fishes, Carangiodes armatus, C. malabaricus and Megalaspis cordyla which were collected from northwest of the Arab Gulf. This species are recorded for the first time in the Iraqi territorial waters of the Arab Gulf. C. armatus, C. malabaricus and M. cordyla are new hosts for this parasite in the Arab Gulf.Keywords: Pseudogrillotia spratti, Carangiodes armatus, C. malabaricus, Megalaspis cordyla, Arab gulf, Iraq
Procedia PDF Downloads 41911268 Systemic Approach to Risk Measurement of Drainage Systems in Urban Areas
Authors: Jadwiga Królikowska, Andrzej Królikowski, Jarosław Bajer
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The work delineates the threats of maladjustment of the capacity of rain canals, designed and built in the early 20th century, in connection to heavy rainfall, especially in summer. This is the cause of the so called 'urban floods.' It directly relates to fierce raise of paving in the cities. Resolving this problem requires a change in philosophy of draining the rainfall by wider use of retention, infiltration and usage of rainwater. In systemic approach to managing the safety of urban drainage systems the risk, which is directly connected to safety failures, has been accepted as a measure. The risk level defines the probability of occurrence of losses greater than the ones forecast for a given time frame. The procedure of risk modelling, enabling its numeric analysis by using appropriate weights, is a significant issue in this paper.Keywords: risk management, drainage system, urban areas, urban floods
Procedia PDF Downloads 36111267 The Misuse of Free Cash and Earnings Management: An Analysis of the Extent to Which Board Tenure Mitigates Earnings Management
Authors: Michael McCann
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Managerial theories propose that, in joint stock companies, executives may be tempted to waste excess free cash on unprofitable projects to keep control of resources. In order to conceal their projects' poor performance, they may seek to engage in earnings management. On the one hand, managers may manipulate earnings upwards in order to post ‘good’ performances and safeguard their position. On the other, since managers pursuit of unrewarding investments are likely to lead to low long-term profitability, managers will use negative accruals to reduce current year’s earnings, smoothing earnings over time in order to conceal the negative effects. Agency models argue that boards of directors are delegated by shareholders to ensure that companies are governed properly. Part of that responsibility is ensuring the reliability of financial information. Analyses of the impact of board characteristics, particularly board independence on the misuse of free cash flow and earnings management finds conflicting evidence. However, existing characterizations of board independence do not account for such directors gaining firm-specific knowledge over time, influencing their monitoring ability. Further, there is little analysis of the influence of the relative experience of independent directors and executives on decisions surrounding the use of free cash. This paper contributes to this literature regarding the heterogeneous characteristics of boards by investigating the influence of independent director tenure on earnings management and the relative tenures of independent directors and Chief Executives. A balanced panel dataset comprising 51 companies across 11 annual periods from 2005 to 2015 is used for the analysis. In each annual period, firms were classified as conducting earnings management if they had discretionary accruals in the bottom quartile (downwards) and top quartile (upwards) of the distributed values for the sample. Logistical regressions were conducted to determine the marginal impact of independent board tenure and a number of control variables on the probability of conducting earnings management. The findings indicate that both absolute and relative measures of board independence and experience do not have a significant impact on the likelihood of earnings management. It is the level of free cash flow which is the major influence on the probability of earnings management. Higher free cash flow increases the probability of earnings management significantly. The research also investigates whether board monitoring of earnings management is contingent on the level of free cash flow. However, the results suggest that board monitoring is not amplified when free cash flow is higher. This suggests that the extent of earnings management in companies is determined by a range of company, industry and situation-specific factors.Keywords: corporate governance, boards of directors, agency theory, earnings management
Procedia PDF Downloads 23311266 Low Cost Inertial Sensors Modeling Using Allan Variance
Authors: A. A. Hussen, I. N. Jleta
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Micro-electromechanical system (MEMS) accelerometers and gyroscopes are suitable for the inertial navigation system (INS) of many applications due to the low price, small dimensions and light weight. The main disadvantage in a comparison with classic sensors is a worse long term stability. The estimation accuracy is mostly affected by the time-dependent growth of inertial sensor errors, especially the stochastic errors. In order to eliminate negative effect of these random errors, they must be accurately modeled. Where the key is the successful implementation that depends on how well the noise statistics of the inertial sensors is selected. In this paper, the Allan variance technique will be used in modeling the stochastic errors of the inertial sensors. By performing a simple operation on the entire length of data, a characteristic curve is obtained whose inspection provides a systematic characterization of various random errors contained in the inertial-sensor output data.Keywords: Allan variance, accelerometer, gyroscope, stochastic errors
Procedia PDF Downloads 44211265 Exploration of Various Metrics for Partitioning of Cellular Automata Units for Efficient Reconfiguration of Field Programmable Gate Arrays (FPGAs)
Authors: Peter Tabatt, Christian Siemers
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Using FPGA devices to improve the behavior of time-critical parts of embedded systems is a proven concept for years. With reconfigurable FPGA devices, the logical blocks can be partitioned and grouped into static and dynamic parts. The dynamic parts can be reloaded 'on demand' at runtime. This work uses cellular automata, which are constructed through compilation from (partially restricted) ANSI-C sources, to determine the suitability of various metrics for optimal partitioning. Significant metrics, in this case, are for example the area on the FPGA device for the partition, the pass count for loop constructs and communication characteristics to other partitions. With successful partitioning, it is possible to use smaller FPGA devices for the same requirements as with not reconfigurable FPGA devices or – vice versa – to use the same FPGAs for larger programs.Keywords: reconfigurable FPGA, cellular automata, partitioning, metrics, parallel computing
Procedia PDF Downloads 27211264 Image Compression Using Block Power Method for SVD Decomposition
Authors: El Asnaoui Khalid, Chawki Youness, Aksasse Brahim, Ouanan Mohammed
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In these recent decades, the important and fast growth in the development and demand of multimedia products is contributing to an insufficient in the bandwidth of device and network storage memory. Consequently, the theory of data compression becomes more significant for reducing the data redundancy in order to save more transfer and storage of data. In this context, this paper addresses the problem of the lossless and the near-lossless compression of images. This proposed method is based on Block SVD Power Method that overcomes the disadvantages of Matlab's SVD function. The experimental results show that the proposed algorithm has a better compression performance compared with the existing compression algorithms that use the Matlab's SVD function. In addition, the proposed approach is simple and can provide different degrees of error resilience, which gives, in a short execution time, a better image compression.Keywords: image compression, SVD, block SVD power method, lossless compression, near lossless
Procedia PDF Downloads 38711263 Improvement of Activity of β-galactosidase from Kluyveromyces lactis via Immobilization on Polyethylenimine-Chitosan
Authors: Carlos A. C. G. Neto, Natan C. G. e Silva , Thaís de O. Costa, Luciana R. B. Gonçalves, Maria V. P. Rocha
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β-galactosidases (E.C. 3.2.1.23) are enzymes that have attracted by catalyzing the hydrolysis of lactose and in producing galacto-oligosaccharides by favoring transgalactosylation reactions. These enzymes, when immobilized, can have some enzymatic characteristics substantially improved, and the coating of supports with multifunctional polymers is a promising alternative to enhance the stability of the biocatalysts, among which polyethylenimine (PEI) stands out. PEI has certain properties, such as being a flexible polymer that suits the structure of the enzyme, giving greater stability, especially for multimeric enzymes such as β-galactosidases. Besides that, protects them from environmental variations. The use of chitosan support coated with PEI could improve the catalytic efficiency of β-galactosidase from Kluyveromyces lactis in the transgalactosylation reaction for the production of prebiotics, such as lactulose since this strain is more effective in the hydrolysis reaction. In this context, the aim of the present work was first to develop biocatalysts of β-galactosidase from K. lactis immobilized on chitosan-coated with PEI, determining the immobilization parameters, its operational and thermal stability, and then to apply it in hydrolysis and transgalactolisation reactions to produce lactulose using whey as a substrate. The immobilization of β-galactosidase in chitosan previously functionalized with 0.8% (v/v) glutaraldehyde and then coated with 10% (w/v) PEI solution was evaluated using an enzymatic load of 10 mg protein per gram support. Subsequently, the hydrolysis and transgalactosylation reactions were conducted at 50 °C, 120 RPM for 20 minutes, using whey supplemented with fructose at a ratio of 1:2 lactose/fructose, totaling 200 g/L. Operational stability studies were performed in the same conditions for 10 cycles. Thermal stabilities of biocatalysts were conducted at 50 ºC in 50 mM phosphate buffer, pH 6.6 with 0.1 mM MnCl2. The biocatalyst whose support was coated was named CHI_GLU_PEI_GAL, and the one that was not coated was named CHI_GLU_GAL. The coating of the support with PEI considerably improved the parameters of immobilization. The immobilization yield increased from 56.53% to 97.45%, biocatalyst activity from 38.93 U/g to 95.26 U/g and the efficiency from 3.51% to 6.0% for uncoated and coated support, respectively. The biocatalyst CHI_GLU_PEI_GAL was better than CHI_GLU_GAL in the hydrolysis of lactose and production of lactulose, converting 97.05% of lactose at 5 min of reaction and producing 7.60 g/L lactulose in the same time interval. QUI_GLU_PEI_GAL biocatalyst was stable in the hydrolysis reactions of lactose during the 10 cycles evaluated, converting 73.45% lactose even after the tenth cycle, and in the lactulose production was stable until the fifth cycle evaluated, producing 10.95 g/L lactulose. However, the thermal stability of CHI_GLU_GAL biocatalyst was superior, with a half-life time 6 times higher, probably because the enzyme was immobilized by covalent bonding, which is stronger than adsorption (CHI_GLU_PEI_GAL). Therefore, the strategy of coating the supports with PEI has proven to be effective for the immobilization of β-galactosidase from K. lactis, considerably improving the immobilization parameters, as well as, the catalytic action of the enzyme. Besides that, this process can be economically viable due to the use of an industrial residue as a substrate.Keywords: β-galactosidase, immobilization, kluyveromyces lactis, lactulose, polyethylenimine, transgalactosylation reaction, whey
Procedia PDF Downloads 11111262 Effect of Water Hardness and Free Residual Chlorine on Black Tea Brew
Authors: P. Murugesan, G. Venkateswaran, V. A. Shanmuga Selvan
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Water used for brewing tea plays a major role in the quality of tea. Water with higher hardness gives very dark coloured brew. This study was conducted to determine the effect of water hardness and free residual chlorine on the quality of black tea liquor. Theaflavin (TF) and Thearubigin (TR) levels are lower in comparison with the tea brewed in distilled water. At the same time, there is an increase in High Polymerized Substance (HPS) and Total Liquor Colour (TLC). While water with higher hardness has a negative impact on tea brew, water with high concentration of free residual chlorine did not affect the quality of tea brew.Keywords: Theaflavin, Thearubigin, high polymerised substance, total liquor colour, hardness, residual chlorine
Procedia PDF Downloads 25711261 Chemical Analysis of Particulate Matter (PM₂.₅) and Volatile Organic Compound Contaminants
Authors: S. Ebadzadsahraei, H. Kazemian
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The main objective of this research was to measure particulate matter (PM₂.₅) and Volatile Organic Compound (VOCs) as two classes of air pollutants, at Prince George (PG) neighborhood in warm and cold seasons. To fulfill this objective, analytical protocols were developed for accurate sampling and measurement of the targeted air pollutants. PM₂.₅ samples were analyzed for their chemical composition (i.e., toxic trace elements) in order to assess their potential source of emission. The City of Prince George, widely known as the capital of northern British Columbia (BC), Canada, has been dealing with air pollution challenges for a long time. The city has several local industries including pulp mills, a refinery, and a couple of asphalt plants that are the primary contributors of industrial VOCs. In this research project, which is the first study of this kind in this region it measures physical and chemical properties of particulate air pollutants (PM₂.₅) at the city neighborhood. Furthermore, this study quantifies the percentage of VOCs at the city air samples. One of the outcomes of this project is updated data about PM₂.₅ and VOCs inventory in the selected neighborhoods. For examining PM₂.₅ chemical composition, an elemental analysis methodology was developed to measure major trace elements including but not limited to mercury and lead. The toxicity of inhaled particulates depends on both their physical and chemical properties; thus, an understanding of aerosol properties is essential for the evaluation of such hazards, and the treatment of such respiratory and other related diseases. Mixed cellulose ester (MCE) filters were selected for this research as a suitable filter for PM₂.₅ air sampling. Chemical analyses were conducted using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for elemental analysis. VOCs measurement of the air samples was performed using a Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) allowing for quantitative measurement of VOC molecules in sub-ppb levels. In this study, sorbent tube (Anasorb CSC, Coconut Charcoal), 6 x 70-mm size, 2 sections, 50/100 mg sorbent, 20/40 mesh was used for VOCs air sampling followed by using solvent extraction and solid-phase micro extraction (SPME) techniques to prepare samples for measuring by a GC-MS/FID instrument. Air sampling for both PM₂.₅ and VOC were conducted in summer and winter seasons for comparison. Average concentrations of PM₂.₅ are very different between wildfire and daily samples. At wildfire time average of concentration is 83.0 μg/m³ and daily samples are 23.7 μg/m³. Also, higher concentrations of iron, nickel and manganese found at all samples and mercury element is found in some samples. It is able to stay too high doses negative effects.Keywords: air pollutants, chemical analysis, particulate matter (PM₂.₅), volatile organic compound, VOCs
Procedia PDF Downloads 14211260 Tracing a Timber Breakthrough: A Qualitative Study of the Introduction of Cross-Laminated-Timber to the Student Housing Market in Norway
Authors: Marius Nygaard, Ona Flindall
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The Palisaden student housing project was completed in August 2013 and was, with its eight floors, Norway’s tallest timber building at the time of completion. It was the first time cross-laminated-timber (CLT) was utilized at this scale in Norway. The project was the result of a concerted effort by a newly formed management company to establish CLT as a sustainable and financially competitive alternative to conventional steel and concrete systems. The introduction of CLT onto the student housing market proved so successful that by 2017 more than 4000 individual student residences will have been built using the same model of development and construction. The aim of this paper is to identify the key factors that enabled this breakthrough for CLT. It is based on an in-depth study of a series of housing projects and the role of the management company who both instigated and enabled this shift of CLT from the margin to the mainstream. Specifically, it will look at how a new building system was integrated into a marketing strategy that identified a market potential within the existing structure of the construction industry and within the economic restrictions inherent to student housing in Norway. It will show how a key player established a project model that changed both the patterns of cooperation and the information basis for decisions. Based on qualitative semi-structured interviews with managers, contractors and the interdisciplinary teams of consultants (architects, structural engineers, acoustical experts etc.) this paper will trace the introduction, expansion and evolution of CLT-based building systems in the student housing market. It will show how the project management firm’s position in the value chain enabled them to function both as a liaison between contractor and client, and between contractor and producer. A position that allowed them to improve the flow of information. This ensured that CLT was handled on equal terms to other structural solutions in the project specifications, enabling realistic pricing and risk evaluation. Secondly, this paper will describe and discuss how the project management firm established and interacted with a growing network of contractors, architects and engineers to pool expertise and broaden the knowledge base across Norway’s regional markets. Finally, it will examine the role of the client, the building typology, and the industrial and technological factors in achieving this breakthrough for CLT in the construction industry. This paper gives an in-depth view of the progression of a single case rather than a broad description of the state of the art of large-scale timber building in Norway. However, this type of study may offer insights that are important to the understanding not only of specific markets but also of how new technologies should be introduced in big and well-established industries.Keywords: cross-laminated-timber (CLT), industry breakthrough, student housing, timber market
Procedia PDF Downloads 22311259 Elaboration and Characterization of CdxZn1-XS Thin Films Deposed by Chemical Bath Deposition
Authors: Zellagui Rahima, Chaumont Denis, Boughelout Abderrahman, Adnane Mohamed
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Thin films of CdxZn1-xS were deposed by chemical bath deposition on glass substrates for photovoltaic applications. The thin films CdZnS were synthesized by chemical bath (CBD) with different deposition protocols for optimized the parameter of deposition as the temperature, time of deposition, concentrations of ion and pH. Surface morphology, optical and chemical composition properties of thin film CdZnS were investigated by SEM, EDAX, spectrophotometer. The transmittance is 80% in visible region 300 nm – 1000 nm; it has been observed in that films the grain size is between 50nm and 100nm measured by SEM image and we also note that the shape of particle is changing with the change in concentration. This result favors of application these films in solar cells; the chemical analysis with EDAX gives information about the presence of Cd, Zn and S elements and investigates the stoichiometry.Keywords: thin film, solar cells, transmition, cdzns
Procedia PDF Downloads 26211258 Performance Analysis of Artificial Neural Network Based Land Cover Classification
Authors: Najam Aziz, Nasru Minallah, Ahmad Junaid, Kashaf Gul
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Landcover classification using automated classification techniques, while employing remotely sensed multi-spectral imagery, is one of the promising areas of research. Different land conditions at different time are captured through satellite and monitored by applying different classification algorithms in specific environment. In this paper, a SPOT-5 image provided by SUPARCO has been studied and classified in Environment for Visual Interpretation (ENVI), a tool widely used in remote sensing. Then, Artificial Neural Network (ANN) classification technique is used to detect the land cover changes in Abbottabad district. Obtained results are compared with a pixel based Distance classifier. The results show that ANN gives the better overall accuracy of 99.20% and Kappa coefficient value of 0.98 over the Mahalanobis Distance Classifier.Keywords: landcover classification, artificial neural network, remote sensing, SPOT 5
Procedia PDF Downloads 54611257 Creating a Virtual Perception for Upper Limb Rehabilitation
Authors: Nina Robson, Kenneth John Faller II, Vishalkumar Ahir, Arthur Ricardo Deps Miguel Ferreira, John Buchanan, Amarnath Banerjee
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This paper describes the development of a virtual-reality system ARWED, which will be used in physical rehabilitation of patients with reduced upper extremity mobility to increase limb Active Range of Motion (AROM). The ARWED system performs a symmetric reflection and real-time mapping of the patient’s healthy limb on to their most affected limb, tapping into the mirror neuron system and facilitating the initial learning phase. Using the ARWED, future experiments will test the extension of the action-observation priming effect linked to the mirror-neuron system on healthy subjects and then stroke patients.Keywords: physical rehabilitation, mirror neuron, virtual reality, stroke therapy
Procedia PDF Downloads 43211256 Disaster Capitalism, Charter Schools, and the Reproduction of Inequality in Poor, Disabled Students: An Ethnographic Case Study
Authors: Sylvia Mac
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This ethnographic case study examines disaster capitalism, neoliberal market-based school reforms, and disability through the lens of Disability Studies in Education. More specifically, it explores neoliberalism and special education at a small, urban charter school in a large city in California and the (re)production of social inequality. The study uses Sociology of Special Education to examine the ways in which special education is used to sort and stratify disabled students. At a time when rhetoric surrounding public schools is framed in catastrophic and dismal language in order to justify the privatization of public education, small urban charter schools must be examined to learn if they are living up to their promise or acting as another way to maintain economic and racial segregation. The study concludes that neoliberal contexts threaten successful inclusive education and normalize poor, disabled students’ continued low achievement and poor post-secondary outcomes. This ethnographic case study took place at a small urban charter school in a large city in California. Participants included three special education students, the special education teacher, the special education assistant, a regular education teacher, and the two founders and charter writers. The school claimed to have a push-in model of special education where all special education students were fully included in the general education classroom. Although presented as fully inclusive, some special education students also attended a pull-out class called Study Skills. The study found that inclusion and neoliberalism are differing ideologies that cannot co-exist. Successful inclusive environments cannot thrive while under the influences of neoliberal education policies such as efficiency and cost-cutting. Additionally, the push for students to join the global knowledge economy means that more and more low attainers are further marginalized and kept in poverty. At this school, neoliberal ideology eclipsed the promise of inclusive education for special education students. This case study has shown the need for inclusive education to be interrogated through lenses that consider macro factors, such as neoliberal ideology in public education, as well as the emerging global knowledge economy and increasing income inequality. Barriers to inclusion inside the school, such as teachers’ attitudes, teacher preparedness, and school infrastructure paint only part of the picture. Inclusive education is also threatened by neoliberal ideology that shifts the responsibility from the state to the individual. This ideology is dangerous because it reifies the stereotypes of disabled students as lazy, needs drains on already dwindling budgets. If these stereotypes persist, inclusive education will have a difficult time succeeding. In order to more fully examine the ways in which inclusive education can become truly emancipatory, we need more analysis on the relationship between neoliberalism, disability, and special education.Keywords: case study, disaster capitalism, inclusive education, neoliberalism
Procedia PDF Downloads 22011255 Synthesis of Biolubricant Base Stock from Palm Methyl Ester
Authors: Nur Sulihatimarsyila Abd Wafti, Harrison Lik Nang Lau, Nabilah Kamaliah Mustaffa, Nur Azreena Idris
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The use of biolubricant has gained its popularity over the last decade. Base stock produced using methyl ester and trimethylolethane (TME) can be potentially used for biolubricant production due to its biodegradability, non-toxicity and good thermal stability. The synthesis of biolubricant base stock e.g. triester (TE) via transesterification of palm methyl ester and TME in the presence of sodium methoxide as the catalyst was conducted. Factors influencing the reaction conditions were investigated including reaction time, temperature and pressure. The palm-based biolubricant base stock produced was analysed for its monoester (ME), diester (DE) and TE contents using gas chromatography as well as its lubricating properties such as viscosity, viscosity index, oxidation stability, and density. The resulting base stock containing 90 wt% TE was successfully synthesized.Keywords: biolubricant, methyl ester, triester transesterification, lubricating properties
Procedia PDF Downloads 44511254 The Effect of Regulation and Investment in Sustainable Practices on Environmental Performance and Consumer Trust: a Time Series Analysis of the Dominant Companies within the Energy Sector
Authors: Sempiga Olivier, Dominika Latusek-Jurczak
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Climate change has allegedly been attributed to a high consumption of fossil fuels, leading to severe environmental problems. The energy sector has been among the most polluting sectors for many decades. Consequently, there is a lack of trust in several energy firms, especially those in fossil fuels and nuclear energy. A robust regulatory framework is needed, and more investment in renewable energy sources is paramount for a better environmental outcome. Given the significant environmental impact of energy production and consumption in the energy sector, sustainable marketing practices have become increasingly important. Although the latter has had the lion’s share in polluting the environment, much effort has been made recently to move away from fossil fuels and privilege renewable energy sources. How this shift would help rebuild trust in the energy industry is unclear. For the shift to have lasting effects, it may be essential that regulatory agencies examine how energy firms engage in sustainable investment. There is little empirical evidence on whether adopting regulating marketing practices and investment initiatives can help different organizations reduce their environmental impact and promote sustainable development. Little is known about how and whether the environmental value in firms goes beyond rhetoric, greenwashing and publicity to translate into economic gains and environmental performance. The study investigates how regulatory agencies can help energy firms invest sustainably and take sustainable initiatives even amid the energy crisis caused by the Russia-Ukraine conflict and how these sustainable practices relate to renewed consumer trust. Using data from Corporate Knights, the study, through time series, analyses the relationship between sustainable regulation, sustainable practices of energy firms from around the world and their relation to consumer trust and environmental performance over the past 20 years. It examines how their sustainable investment, energy, and carbon productivity relate to environmental sustainability and consumer trust. This longitudinal study provides empirical evidence of the interplay between regulation, trust and environmental performance. The research is grounded in institutional trust theory, which emphasizes the role of regulatory frameworks and organizational practices in shaping public perceptions of fairness, transparency, and legitimacy. Results show that organizations in the energy sector, supported by robust regulatory tools, can overcome the negative image of polluters and compete with other companies in the fight against climate change and global warming. However, to do so, energy firms should consider investing more in renewable energy sources and implementing sustainable strategies and practices that go beyond greenwashing to improve their environmental performance, thereby rebuilding consumer trust in the energy sector. Results allow regulatory regimes and organizations to learn why it is crucial for energy firms to invest in renewable energy sources and engage in various sustainable initiatives and practices to contribute to better environmental outcomes and higher levels of trust.Keywords: consumer trust, energy, environmental performance, regulation, renewable energy sources, sustainable practices
Procedia PDF Downloads 911253 An Implicit Methodology for the Numerical Modeling of Locally Inextensible Membranes
Authors: Aymen Laadhari
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We present in this paper a fully implicit finite element method tailored for the numerical modeling of inextensible fluidic membranes in a surrounding Newtonian fluid. We consider a highly simplified version of the Canham-Helfrich model for phospholipid membranes, in which the bending force and spontaneous curvature are disregarded. The coupled problem is formulated in a fully Eulerian framework and the membrane motion is tracked using the level set method. The resulting nonlinear problem is solved by a Newton-Raphson strategy, featuring a quadratic convergence behavior. A monolithic solver is implemented, and we report several numerical experiments aimed at model validation and illustrating the accuracy of the proposed method. We show that stability is maintained for significantly larger time steps with respect to an explicit decoupling method.Keywords: finite element method, level set, Newton, membrane
Procedia PDF Downloads 33011252 Computational Quantum Mechanics Study of Oxygen as Substitutional Atom in Diamond
Authors: K. M. Etmimi, A. A. Sghayer, A. M. Gsiea, A. M. Abutruma
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Relatively few chemical species can be incorporated into diamond during CVD growth, and until recently the uptake of oxygen was thought to be low perhaps as a consequence of a short surface residence time. Within the literature, there is speculation regarding spectroscopic evidence for O in diamond, but no direct evidence. For example, the N3 and OK1 EPR centres have been tentatively assigned models made up from complexes of substitutional N and substitutional oxygen. In this study, we report density-functional calculations regarding the stability, electronic structures, geometry and hyperfine interaction of substitutional oxygen in diamond and show that the C2v, S=1 configuration very slightly lower in energy than the other configurations (C3v, Td, and C2v with S=0). The electronic structure of O in diamond generally gives rise to two defect-related energy states in the band gap one a non-degenerate a1 state lying near the middle of the energy gap and the other a threefold-degenerate t2 state located close to the conduction band edges. The anti-bonding a1 and t2 states will be occupied by one to three electrons for O+, O and O− respectively.Keywords: DFT, oxygen, diamond, hyperfine
Procedia PDF Downloads 37511251 Effect of Using Crumb Rubber with Warm-Mix-Asphalt Additive in Laboratory and Field Aging
Authors: Mustafa Akpolat, Baha Vural Kök
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Using a waste material such as crumb rubber (CR) obtained by waste tires has become an important issue in respect to sustainability. However, the CR modified mixture also requires high manufacture temperature as a polymer modified mixture. For this reason in this study, it is intended to produce a CR modified mixture with warm mix asphalt additives in the same mixture. Asphalt mixtures produced by pure, 10%CR, 10%CR+3% Sasobit and 10%CR+0.7% Evotherm were subjected to aging procedure in the laboratory and the field. The indirect tensile repeated tests were applied to aged and original specimens. It was concluded that the fatigue life of the mixtures increased significantly with the increase of aging time. CR+Sasobit modified mixture aged at the both field and laboratory gave the highest load cycle among the mixtures.Keywords: crumb rubber, warm mix asphalt, aging, fatigue
Procedia PDF Downloads 40211250 Retraction Free Motion Approach and Its Application in Automated Robotic Edge Finishing and Inspection Processes
Authors: M. Nemer, E. I. Konukseven
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In this paper, a motion generation algorithm for a six Degrees of Freedom (DoF) robotic hand in a static environment is presented. The purpose of developing this method is to be used in the path generation of the end-effector for edge finishing and inspection processes by utilizing the CAD model of the considered workpiece. Nonetheless, the proposed algorithm may be extended to be applicable for other similar manufacturing processes. A software package programmed in the application programming interface (API) of SolidWorks generates tool path data for the robot. The proposed method significantly simplifies the given problem, resulting in a reduction in the CPU time needed to generate the path, and offers an efficient overall solution. The ABB IRB2000 robot is chosen for executing the generated tool path.Keywords: CAD-based tools, edge deburring, edge scanning, offline programming, path generation
Procedia PDF Downloads 28411249 The Relationship of Television Viewers with Brand Awareness and Brand Loyalty: A Case Study of Bangkok, Thailand
Authors: Natnicha Hasoontree
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The purposes of this research was to study the relationship of television viewers with brand awareness and brand loyalty from the perspective of customers in Bangkok. A probability random sampling of 482 television viewers was utilized. A Likert-five-scale questionnaire was designed to collect the data and small in-depth interviews were also used to obtain their opinions. The findings revealed that the majority of respondents reported a positive relationship between time of viewing television and brand awareness and brand loyalty. The more they watched the advertisement of a particular brand, the more positive the information was perceived and thereby increasing brand loyalty. Finally, the findings from the in-depth interviews with small group of television producers revealed that they are convinced that advertising exposure had a positive impact on brand awareness and brand loyalty.Keywords: brand awareness, brand loyalty, television viewers, advertisement
Procedia PDF Downloads 31211248 Chromium Adsorption by Modified Wood
Authors: I. Domingos, B. Esteves, A. Figueirinha, Luísa P. Cruz-Lopes, J. Ferreira, H. Pereira
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Chromium is one of the most common heavy metals which exist in very high concentrations in wastewater. The removal is very expensive due to the high cost of normal adsorbents. Lignocellulosic materials and mainly treated materials have proven to be a good solution for this problem. Adsorption tests were performed at different pH, different times and with varying concentrations. Results show that is at pH 3 that treated wood absorbs more chromium ranging from 70% (2h treatment) to almost 100% (12 h treatment) much more than untreated wood with less than 40%. Most of the adsorption is made in the first 2-3 hours for untreated and heat treated wood. Modified wood adsorbs more chromium throughout the time. For all the samples, adsorption fitted relatively well the Langmuir model with correlation coefficient ranging from 0.85 to 0.97. The results show that heat treated wood is a good adsorbent ant that this might be a good utilization for sawdust from treating companies.Keywords: adsorption, chromium, heat treatment, wood modification
Procedia PDF Downloads 49911247 Efficiency of Virtual Reality Exercises with Nintendo Wii System on Balance and Independence in Motor Functions in Hemiparetic Patients: A Randomized Controlled Study
Authors: Ayça Utkan Karasu, Elif Balevi Batur, Gülçin Kaymak Karataş
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The aim of this study was to examine the efficiency of virtual reality exercises with Nintendo Wii system on balance and independence in motor functions. This randomized controlled assessor-blinded study included 23 stroke inpatients with hemiparesis all within 12 months poststroke. Patients were randomly assigned to control group (n=11) or experimental group (n=12) via block randomization method. Control group participated in a conventional balance rehabilitation programme. Study group received a four-week balance training programme five times per week with a session duration of 20 minutes in addition to the conventional balance rehabilitation programme. Balance was assessed by the Berg’s balance scale, the functional reach test, the timed up and go test, the postural assessment scale for stroke, the static balance index. Also, displacement of centre of pressure sway and centre of pressure displacement during weight shifting was calculated by Emed-SX system. Independence in motor functions was assessed by The Functional Independence Measure (FIM) ambulation and FIM transfer subscales. The outcome measures were evaluated at baseline, 4th week (posttreatment), 8th week (follow-up). Repeated measures analysis of variance was performed for each of the outcome measure. Significant group time interaction was detected in the scores of the Berg’s balance scale, the functional reach test, eyes open anteroposterior and mediolateral center of pressure sway distance, eyes closed anteroposterior center of pressure sway distance, center of pressure displacement during weight shifting to effected side, unaffected side and total centre of pressure displacement during weight shifting (p < 0.05). Time effect was statistically significant in the scores of the Berg’s balance scale, the functional reach test, the timed up and go test, the postural assessment scale for stroke, the static balance index, eyes open anteroposterior and mediolateral center of pressure sway distance, eyes closed mediolateral center of pressure sway distance, the center of pressure displacement during weight shifting to effected side, the functional independence measure ambulation and transfer scores (p < 0.05). Virtual reality exercises with Nintendo Wii system combined with a conventional balance rehabilitation programme enhances balance performance and independence in motor functions in stroke patients.Keywords: balance, hemiplegia, stroke rehabilitation, virtual reality
Procedia PDF Downloads 22111246 In Agile Projects - Arithmetic Sequence is More Effective than Fibonacci Sequence to Use for Estimating the Implementation Effort of User Stories
Authors: Khaled Jaber
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The estimation of effort in software development is a complex task. The traditional Waterfall approach used to develop software systems requires a lot of time to estimate the effort needed to implement user requirements. Agile manifesto, however, is currently more used in the industry than the Waterfall to develop software systems. In Agile, the user requirement is referred to as a user story. Agile teams mostly use the Fibonacci sequence 1, 2, 3, 5, 8, 11, etc. in estimating the effort needed to implement the user story. This work shows through analysis that the Arithmetic sequence, e.g., 3, 6, 9, 12, etc., is more effective than the Fibonacci sequence in estimating the user stories. This paper mathematically and visually proves the effectiveness of the Arithmetic sequence over the FB sequence.Keywords: agie, scrum, estimation, fibonacci sequence
Procedia PDF Downloads 20511245 De-Pigmentary Effect of Ayurvedic Treatment on Hyper-Pigmentation of Skin Due to Chloroquine: A Case Report
Authors: Sunil Kumar, Rajesh Sharma
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Toxic epidermal necrolysis, pruritis, rashes, lichen planus like eruption, hyper pigmentation of skin are rare toxic effects of choloroquine used over a long time. Skin and mucus membrane hyper pigmentation is generally of a bluish black or grayish color and irreversible after discontinuation of the drug. According to Ayurveda, Dushivisha is the name given to any poisonous substance which is not fully endowed with the qualities of poison by nature (i.e. it acts as an impoverished or weak poison) and because of its mild potency, it remains in the body for many years causing various symptoms, one among them being discoloration of skin.The objective of this case report is to investigate the effect of Ayurvedic management of chloroquine induced hyper-pigmentation on the line of treatment of Dushivisha. Case Report: A 26-year-old female was suffering from hyper-pigmentation of the skin over the neck, forehead, temporo-mandibular joints, upper back and posterior aspect of both the arms since 8 years had history of taking Chloroquine came to Out Patient Department of National Institute of Ayurveda, Jaipur, India in Jan. 2015. The routine investigations (CBC, ESR, Eosinophil count) were within normal limits. Punch biopsy skin studied for histopathology under hematoxylin and eosin staining showed epidermis with hyper-pigmentation of the basal layer. In the papillary dermis as well as deep dermis there were scattered melanophages along with infiltration by mononuclear cells. There was no deposition of amyloid-like substances. These histopathological findings were suggestive of Chloroquine induced hyper-pigmentation. The case was treated on the line of treatment of Dushivisha and was given Vamana and Virechana (therapeutic emesis and purgation) every six months followed by Snehana karma (oleation therapy) with Panchatikta Ghrit and Swedana (sudation). Arogyavardhini Vati -1 g, Dushivishari Vati 500 mg, Mahamanjisthadi Quath 20 ml were given twelve hourly and Aragwadhadi Quath 25 ml at bed time orally. The patient started showing lightening of the pigments after six months and almost complete remission after 12 months of the treatment. Conclusion: This patient presented with the Dushivisha effect of Chloroquineandwas administered two relevant procedures from Panchakarma viz. Vamana and Virechana. Both Vamana and Virechanakarma here referred to Shodhana karma (purification procedures) eliminates accumulated toxins from the body. In this process, oleation dislodge the toxins from the tissues and sudation helps to bring them to the alimentary tract. The line of treatment did not target direct hypo pigmentary effects; rather aimed to eliminate the Dushivisha. This gave promising results in this condition.Keywords: Ayurveda, chloroquine, Dushivisha, hyper-pigmentation
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