Search results for: performance of process
15219 Underground Coal Gasification Technology in Türkiye: A Techno-Economic Assessment
Authors: Fatma Ünal, Hasancan Okutan
Abstract:
Increasing worldwide population and technological requirements lead to an increase in energy demand every year. The demand has been mainly supplied from fossil fuels such as coal and petroleum due to insufficient natural gas resources. In recent years, the amount of coal reserves has reached almost 21 billion tons in Türkiye. These are mostly lignite (%92,7), that contains high levels of moisture and sulfur components. Underground coal gasification technology is one of the most suitable methods in comparison with direct combustion techniques for the evaluation of such coal types. In this study, the applicability of the underground coal gasification process is investigated in the Eskişehir-Alpu lignite reserve as a pilot region, both technologically and economically. It is assumed that the electricity is produced from the obtained synthesis gas in an integrated gasification combined cycle (IGCC). Firstly, an equilibrium model has been developed by using the thermodynamic properties of the gasification reactions. The effect of the type of oxidizing gas, the sulfur content of coal, the rate of water vapor/air, and the pressure of the system have been investigated to find optimum process conditions. Secondly, the parallel and linear controlled recreation and injection point (CRIP) models were implemented as drilling methods, and costs were calculated under the different oxidizing agents (air and high-purity O2). In Parallel CRIP (P-CRIP), drilling cost is found to be lower than the linear CRIP (L-CRIP) since two coal beds simultaneously are gasified. It is seen that CO2 Capture and Storage (CCS) technology was the most effective unit on the total cost in both models. The cost of the synthesis gas produced varies between 0,02 $/Mcal and 0,09 $/Mcal. This is the promising result when considering the selling price of Türkiye natural gas for Q1-2023 (0.103 $ /Mcal).Keywords: energy, lignite reserve, techno-economic analysis, underground coal gasification.
Procedia PDF Downloads 6515218 Optimization of Ultrasound-Assisted Extraction of Oil from Spent Coffee Grounds Using a Central Composite Rotatable Design
Authors: Malek Miladi, Miguel Vegara, Maria Perez-Infantes, Khaled Mohamed Ramadan, Antonio Ruiz-Canales, Damaris Nunez-Gomez
Abstract:
Coffee is the second consumed commodity worldwide, yet it also generates colossal waste. Proper management of coffee waste is proposed by converting them into products with higher added value to achieve sustainability of the economic and ecological footprint and protect the environment. Based on this, a study looking at the recovery of coffee waste is becoming more relevant in recent decades. Spent coffee grounds (SCG's) resulted from brewing coffee represents the major waste produced among all coffee industry. The fact that SCGs has no economic value be abundant in nature and industry, do not compete with agriculture and especially its high oil content (between 7-15% from its total dry matter weight depending on the coffee varieties, Arabica or Robusta), encourages its use as a sustainable feedstock for bio-oil production. The bio-oil extraction is a crucial step towards biodiesel production by the transesterification process. However, conventional methods used for oil extraction are not recommended due to their high consumption of energy, time, and generation of toxic volatile organic solvents. Thus, finding a sustainable, economical, and efficient extraction technique is crucial to scale up the process and to ensure more environment-friendly production. Under this perspective, the aim of this work was the statistical study to know an efficient strategy for oil extraction by n-hexane using indirect sonication. The coffee waste mixed Arabica and Robusta, which was used in this work. The temperature effect, sonication time, and solvent-to-solid ratio on the oil yield were statistically investigated as dependent variables by Central Composite Rotatable Design (CCRD) 23. The results were analyzed using STATISTICA 7 StatSoft software. The CCRD showed the significance of all the variables tested (P < 0.05) on the process output. The validation of the model by analysis of variance (ANOVA) showed good adjustment for the results obtained for a 95% confidence interval, and also, the predicted values graph vs. experimental values confirmed the satisfactory correlation between the model results. Besides, the identification of the optimum experimental conditions was based on the study of the surface response graphs (2-D and 3-D) and the critical statistical values. Based on the CCDR results, 29 ºC, 56.6 min, and solvent-to-solid ratio 16 were the better experimental conditions defined statistically for coffee waste oil extraction using n-hexane as solvent. In these conditions, the oil yield was >9% in all cases. The results confirmed the efficiency of using an ultrasound bath in extracting oil as a more economical, green, and efficient way when compared to the Soxhlet method.Keywords: coffee waste, optimization, oil yield, statistical planning
Procedia PDF Downloads 11815217 Simulation of Channel Models for Device-to-Device Application of 5G Urban Microcell Scenario
Authors: H. Zormati, J. Chebil, J. Bel Hadj Tahar
Abstract:
Next generation wireless transmission technology (5G) is expected to support the development of channel models for higher frequency bands, so clarification of high frequency bands is the most important issue in radio propagation research for 5G, multiple urban microcellular measurements have been carried out at 60 GHz. In this paper, the collected data is uniformly analyzed with focus on the path loss (PL), the objective is to compare simulation results of some studied channel models with the purpose of testing the performance of each one.Keywords: 5G, channel model, 60GHz channel, millimeter-wave, urban microcell
Procedia PDF Downloads 31815216 Static Test Pad for Solid Rocket Motors
Authors: Svanik Garg
Abstract:
Static Test Pads are stationary mechanisms that hold a solid rocket motor, measuring the different parameters of its operation including thrust and temperature to better calibrate it for launch. This paper outlines a specific STP designed to test high powered rocket motors with a thrust upwards of 4000N and limited to 6500N. The design includes a specific portable mechanism with cost an integral part of the design process to make it accessible to small scale rocket developers with limited resources. Using curved surfaces and an ergonomic design, the STP has a delicately engineered façade/case with a focus on stability and axial calibration of thrust. This paper describes the design, operation and working of the STP and its widescale uses given the growing market of aviation enthusiasts. Simulations on the CAD model in Fusion 360 provided promising results with a safety factor of 2 established and stress limited along with the load coefficient A PCB was also designed as part of the test pad design process to help obtain results, with visual output and various virtual terminals to collect data of different parameters. The circuitry was simulated using ‘proteus’ and a special virtual interface with auditory commands was also created for accessibility and wide-scale implementation. Along with this description of the design, the paper also emphasizes the design principle behind the STP including a description of its vertical orientation to maximize thrust accuracy along with a stable base to prevent micromovements. Given the rise of students and professionals alike building high powered rockets, the STP described in this paper is an appropriate option, with limited cost, portability, accuracy, and versatility. There are two types of STP’s vertical or horizontal, the one discussed in this paper is vertical to utilize the axial component of thrust.Keywords: static test pad, rocket motor, thrust, load, circuit, avionics, drag
Procedia PDF Downloads 37615215 Improving the Training for Civil Engineers by Introducing Virtual Reality Technique
Authors: Manar Al-Ateeq
Abstract:
The building construction industry plays a major role in the economy of the word and the state of Kuwait. This paper evaluates existing new civil site engineers, describes a new system for improvement and insures the importance of prequalifying and developing for new engineers. In order to have a strong base in engineering, educational institutes and workplaces should be responsible to continuously train engineers and update them with new methods and techniques in engineering. As to achieve that, school of engineering should constantly update computational resources to be used in the professions. A survey was prepared for graduated Engineers based on stated objectives to understand the status of graduate engineers in both the public and private sector. Interviews were made with different sectors in Kuwait, and several visits were made to different training centers within different workplaces in Kuwait to evaluate training process and try to improve it. Virtual Reality (VR) technology could be applied as a complement to three-dimensional (3D) modeling, leading to better communication whether in job training, in education or in professional practice. Techniques of 3D modeling and VR can be applied to develop the models related to the construction process. The 3D models can support rehabilitation design as it can be considered as a great tool for monitoring failure and defaults in structures; also it can support decisions based on the visual analyses of alternative solutions. Therefore, teaching computer-aided design (CAD) and VR techniques in school will help engineering students in order to prepare them to site work and also will assist them to consider these technologies as important supports in their later professional practice. This teaching technique will show how the construction works developed, allow the visual simulation of progression of each type of work and help them to know more about the necessary equipment needed for tasks and how it works on site.Keywords: three dimensional modeling (3DM), civil engineers (CE), professional practice (PP), virtual reality (VR)
Procedia PDF Downloads 17315214 Digital Twin for University Campus: Workflow, Applications and Benefits
Authors: Frederico Fialho Teixeira, Islam Mashaly, Maryam Shafiei, Jurij Karlovsek
Abstract:
The ubiquity of data gathering and smart technologies, advancements in virtual technologies, and the development of the internet of things (IoT) have created urgent demands for the development of frameworks and efficient workflows for data collection, visualisation, and analysis. Digital twin, in different scales of the city into the building, allows for bringing together data from different sources to generate fundamental and illuminating insights for the management of current facilities and the lifecycle of amenities as well as improvement of the performance of current and future designs. Over the past two decades, there has been growing interest in the topic of digital twin and their applications in city and building scales. Most such studies look at the urban environment through a homogeneous or generalist lens and lack specificity in particular characteristics or identities, which define an urban university campus. Bridging this knowledge gap, this paper offers a framework for developing a digital twin for a university campus that, with some modifications, could provide insights for any large-scale digital twin settings like towns and cities. It showcases how currently unused data could be purposefully combined, interpolated and visualised for producing analysis-ready data (such as flood or energy simulations or functional and occupancy maps), highlighting the potential applications of such a framework for campus planning and policymaking. The research integrates campus-level data layers into one spatial information repository and casts light on critical data clusters for the digital twin at the campus level. The paper also seeks to raise insightful and directive questions on how digital twin for campus can be extrapolated to city-scale digital twin. The outcomes of the paper, thus, inform future projects for the development of large-scale digital twin as well as urban and architectural researchers on potential applications of digital twin in future design, management, and sustainable planning, to predict problems, calculate risks, decrease management costs, and improve performance.Keywords: digital twin, smart campus, framework, data collection, point cloud
Procedia PDF Downloads 6615213 Optimisation of Dyes Decolourisation by Bacillus aryabhattai
Authors: A. Paz, S. Cortés Diéguez, J. M. Cruz, A. B. Moldes, J. M. Domínguez
Abstract:
Synthetic dyes are extensively used in the paper, food, leather, cosmetics, pharmaceutical and textile industries. Wastewater resulting from their production means several environmental problems. Improper disposal of theirs effluents involves adverse impacts and not only about the colour, also on water quality (Total Organic Carbon, Biological Oxygen Demand, Chemical Oxygen Demand, suspended solids, salinity, etc.) on flora (inhibition of photosynthetic activity), fauna (toxic, carcinogenic, and mutagenic effects) and human health. The aim of this work is to optimize the decolourisation process of different types of dyes by Bacillus aryabhattai. Initially, different types of dyes (Indigo Carmine, Coomassie Brilliant Blue and Remazol Brilliant Blue R) and suitable culture media (Nutritive Broth, Luria Bertani Broth and Trypticasein Soy Broth) were selected. Then, a central composite design (CCD) was employed to optimise and analyse the significance of each abiotic parameter. Three process variables (temperature, salt concentration and agitation) were investigated in the CCD at 3 levels with 2-star points. A total of 23 experiments were carried out according to a full factorial design, consisting of 8 factorial experiments (coded to the usual ± 1 notation), 6 axial experiments (on the axis at a distance of ± α from the centre), and 9 replicates (at the centre of the experimental domain). Experiments results suggest the efficiency of this strain to remove the tested dyes on the 3 media studied, although Trypticasein Soy Broth (TSB) was the most suitable medium. Indigo Carmine and Coomassie Brilliant Blue at maximal tested concentration 150 mg/l were completely decolourised, meanwhile, an acceptable removal was observed using the more complicate dye Remazol Brilliant Blue R at a concentration of 50 mg/l.Keywords: Bacillus aryabhattai, dyes, decolourisation, central composite design
Procedia PDF Downloads 21815212 Dissolution of South African Limestone for Wet Flue Gas Desulphurization
Authors: Lawrence Koech, Ray Everson, Hein Neomagus, Hilary Rutto
Abstract:
Wet Flue gas desulphurization (FGD) systems are commonly used to remove sulphur dioxide from flue gas by contacting it with limestone in aqueous phase which is obtained by dissolution. Dissolution is important as it affects the overall performance of a wet FGD system. In the present study, effects of pH, stirring speed, solid to liquid ratio and acid concentration on the dissolution of limestone using an organic acid (adipic acid) were investigated. This was investigated using the pH stat apparatus. Calcium ions were analyzed at the end of each experiment using Atomic Absorption (AAS) machine.Keywords: desulphurization, limestone, dissolution, pH stat apparatus
Procedia PDF Downloads 45915211 Urban Open Source: Synthesis of a Citizen-Centric Framework to Design Densifying Cities
Authors: Shaurya Chauhan, Sagar Gupta
Abstract:
Prominent urbanizing centres across the globe like Delhi, Dhaka, or Manila have exhibited that development often faces a challenge in bridging the gap among the top-down collective requirements of the city and the bottom-up individual aspirations of the ever-diversifying population. When this exclusion is intertwined with rapid urbanization and diversifying urban demography: unplanned sprawl, poor planning, and low-density development emerge as automated responses. In parallel, new ideas and methods of densification and public participation are being widely adopted as sustainable alternatives for the future of urban development. This research advocates a collaborative design method for future development: one that allows rapid application with its prototypical nature and an inclusive approach with mediation between the 'user' and the 'urban', purely with the use of empirical tools. Building upon the concepts and principles of 'open-sourcing' in design, the research establishes a design framework that serves the current user requirements while allowing for future citizen-driven modifications. This is synthesized as a 3-tiered model: user needs – design ideology – adaptive details. The research culminates into a context-responsive 'open source project development framework' (hereinafter, referred to as OSPDF) that can be used for on-ground field applications. To bring forward specifics, the research looks at a 300-acre redevelopment in the core of a rapidly urbanizing city as a case encompassing extreme physical, demographic, and economic diversity. The suggestive measures also integrate the region’s cultural identity and social character with the diverse citizen aspirations, using architecture and urban design tools, and references from recognized literature. This framework, based on a vision – feedback – execution loop, is used for hypothetical development at the five prevalent scales in design: master planning, urban design, architecture, tectonics, and modularity, in a chronological manner. At each of these scales, the possible approaches and avenues for open- sourcing are identified and validated, through hit-and-trial, and subsequently recorded. The research attempts to re-calibrate the architectural design process and make it more responsive and people-centric. Analytical tools such as Space, Event, and Movement by Bernard Tschumi and Five-Point Mental Map by Kevin Lynch, among others, are deep rooted in the research process. Over the five-part OSPDF, a two-part subsidiary process is also suggested after each cycle of application, for a continued appraisal and refinement of the framework and urban fabric with time. The research is an exploration – of the possibilities for an architect – to adopt the new role of a 'mediator' in development of the contemporary urbanity.Keywords: open source, public participation, urbanization, urban development
Procedia PDF Downloads 14915210 Evaluation of Certain Medicinal Plants for in vitro Anti-Oxidant and Anti-Glycation Activities
Authors: K. Shailaja
Abstract:
The advanced glycation end products (AGEs) formed between the reducing sugar and protein as a result of Oxidative stress and non-enzymatic glycosylation play an important role in pathogenesis of diabetes and aging complication. Glycation results in the production of free radicals. The oxidation process is believed to play an important role in AGEs formation. Thus agents with antioxidative property and antiglycation activity may retard the process of AGEs formation. Selected medicinal plants for the present study include Catharanthus roseus, Bougainvillea spectabilis (pink flowers), Cinnamomum tamala, Cinnamomum zeylanica, Abutilon indicum, Asparagus racemosus, and Sapindus emarginatus. The crude ethanolic extracts of the selected medicinal plants at varying concentrations ranging from 1-100 mg/ml were evaluated for in vitro antioxidant and protein glycation activities by FRAP and glucose-BSA assay respectively. Among all the plants tested, Bougainvillea spectabilis, Catharanthus roseus and Abutilon indicum showed strong antioxidant activity The antioxidant activity was expressed as mg of Gallic acid/ gm sample which was found to be 4.3 mg, 1.3mg, and 1.3mg respectively for Bougainvillea spectabilis, Catharanthus roseus and Abutilon indicum. The results of inhibition of the initial glycation product i.e., fructosamine was found to be 35% for Asparagus racemosus, Cinnamomum tamala and Abutilon indicum followed by the other plant extracts. The results indicate that these plants are potential sources of natural antioxidants which have free radical scavenging activity and might be used not only for reducing oxidative stress in diabetes but also open a new research avenues in the field of Natural Products.Keywords: in vitro antioxidant activity, anti-glycation activity, ethanol extracts, polyphenols, Catharanthus roseus, Cinnamomum tamala
Procedia PDF Downloads 42615209 Leuco Dye-Based Thermochromic Systems for Application in Temperature Sensing
Authors: Magdalena Wilk-Kozubek, Magdalena Rowińska, Krzysztof Rola, Joanna Cybińska
Abstract:
Leuco dye-based thermochromic systems are classified as intelligent materials because they exhibit thermally induced color changes. Thanks to this feature, they are mainly used as temperature sensors in many industrial sectors. For example, placing a thermochromic material on a chemical reactor may warn about exceeding the maximum permitted temperature for a chemical process. Usually two components, a color former and a developer are needed to produce a system with irreversible color change. The color former is an electron donating (proton accepting) compound such as fluoran leuco dye. The developer is an electron accepting (proton donating) compound such as organic carboxylic acid. When the developer melts, the color former - developer complex is created and the termochromic system becomes colored. Typically, the melting point of the applied developer determines the temperature at which the color change occurs. When the lactone ring of the color former is closed, then the dye is in its colorless state. The ring opening, induced by the addition of a proton, causes the dye to turn into its colored state. Since the color former and the developer are often solid, they can be incorporated into polymer films to facilitate their practical use in industry. The objective of this research was to fabricate a leuco dye-based termochromic system that will irreversibly change color after reaching the temperature of 100°C. For this purpose, benzofluoran leuco dye (as color former) and phenoxyacetic acid (as developer with a melting point of 100°C) were introduced into the polymer films during the drop casting process. The film preparation process was optimized in order to obtain thin films with appropriate properties such as transparency, flexibility and homogeneity. Among the optimized factors were the concentration of benzofluoran leuco dye and phenoxyacetic acid, the type, average molecular weight and concentration of the polymer, and the type and concentration of the surfactant. The selected films, containing benzofluoran leuco dye and phenoxyacetic acid, were combined by mild heat treatment. Structural characterization of single and combined films was carried out by FTIR spectroscopy, morphological analysis was performed by optical microscopy and SEM, phase transitions were examined by DSC, color changes were investigated by digital photography and UV-Vis spectroscopy, while emission changes were studied by photoluminescence spectroscopy. The resulting thermochromic system is colorless at room temperature, but after reaching 100°C the developer melts and it turns irreversibly pink. Therefore, it could be used as an additional sensor to warn against boiling of water in power plants using water cooling. Currently used electronic temperature indicators are prone to faults and unwanted third-party actions. The sensor constructed in this work is transparent, thanks to which it can be unnoticed by an outsider and constitute a reliable reference for the person responsible for the apparatus.Keywords: color developer, leuco dye, thin film, thermochromism
Procedia PDF Downloads 9815208 Effects of Robot-Assisted Hand Training on Upper Extremity Performance in Patients with Stroke: A Randomized Crossover Controlled, Assessor-Blinded Study
Authors: Hsin-Chieh Lee, Fen-Ling Kuo, Jui-Chi Lin
Abstract:
Background: Upper extremity functional impairment that occurs after stroke includes hemiplegia, synergy movement, muscle hypertonicity, and somatosensory impairment, which result in inefficient and inaccurate movement. Robot-assisted rehabilitation is an intensive training approach that is effective in sensorimotor and hand function recovery. However, these systems mostly focused on the proximal part of the upper limb rather than the distal part. The device used in our study was Gloreha Sinfonia, which focuses on the distal part of the upper limb and uses a dynamic support system to facilitate the whole limb function. The objective of this study was to investigate the effects of robot-assisted therapy (RT) with Gloreha device on sensorimotor, and ADLs in patients with stroke. Method: Patients with stroke (N=25) participated AB or BA (A = 12 RT sessions and B = 12 conventional therapy (CT) sessions) for 6 weeks (60 min at each session, twice a week), with 1-month break for washout period. The performance of the patients was assessed by a blinded assessor at 4 time points (pretest 1, posttest 1, pretest 2, posttest 2) which including the Fugl–Meyer Assessment-upper extremity (FMA-UE), box and block test, electromyography of the extensor digitorum communis (EDC) and brachioradialis, a grip dynamometer for motor evaluation; Semmes–Weinstein hand monofilament and Revision of the Nottingham Sensory Assessment for sensory evaluation; and the Modified Barthel Index (MBI) for assessing the ADL ability. Result: RT group significantly improved FMA-UE proximal scores (p = 0.038), FMA-UE total scores (p = 0.046), and MBI (p = 0.030). The EDC exhibited higher efficiency during the small block grasping task in the RT group than in the CT group (p = 0.050). Conclusions: RT with the Gloreha device might lead to beneficial effects on arm motor function, ADL ability, and EDC muscle recruitment efficacy in patients with subacute to chronic stroke.Keywords: activities of daily living, hand function, robotic rehabilitation, stroke
Procedia PDF Downloads 11715207 Roads and Agriculture: Impacts of Connectivity in Peru
Authors: Julio Aguirre, Yohnny Campana, Elmer Guerrero, Daniel De La Torre Ugarte
Abstract:
A well-developed transportation network is a necessary condition for a country to derive full benefits from good trade and macroeconomic policies. Road infrastructure plays a key role in the economic development of rural areas of developing countries; where agriculture is the main economic activity. The ability to move agricultural production from the place of production to the market, and then to the place of consumption, greatly influence the economic value of farming activities, and of the resources involved in the production process, i.e., labor and land. Consequently, investment in transportation networks contributes to enhance or overcome the natural advantages or disadvantages that topography and location have imposed over the agricultural sector. This is of particular importance when dealing with countries, like Peru, with a great topographic diversity. The objective of this research is to estimate the impacts of road infrastructure on the performance of the agricultural sector. Specific variables of interest are changes in travel time, shifts of production for self-consumption to production for the market, changes in farmers income, and impacts on the diversification of the agricultural sector. In the study, a cross-section model with instrumental variables is the central methodological instrument. The data is obtained from agricultural and transport geo-referenced databases, and the instrumental variable specification utilized is based on the Kruskal algorithm. The results show that the expansion of road connectivity reduced farmers' travel time by an average of 3.1 hours and the proportion of output sold in the market increases by up to 40 percentage points. The increase in connectivity has an unexpected increase in the districts index of diversification of agricultural production. The results are robust to the inclusion of year and region fixed-effects, and to control for geography (i.e., slope and altitude), population variables, and mining activity. Other results are also very eloquent. For example, a clear positive impact can be seen in access to local markets, but this does not necessarily correlate with an increase in the production of the sector. This can be explained by the fact that agricultural development not only requires provision of roads but additional complementary infrastructure and investments intended to provide the necessary conditions so that producers can offer quality products (improved management practices, timely maintenance of irrigation infrastructure, transparent management of water rights, among other factors). Therefore, complementary public goods are needed to enhance the effects of roads on the welfare of the population, beyond enabling them to increase their access to markets.Keywords: agriculture devolepment, market access, road connectivity, regional development
Procedia PDF Downloads 20515206 Dissolved Black Carbon Accelerates the Photo-Degradation of Polystyrene Microplastics
Authors: Qin Ou, Yanghui Xu, Xintu Wang, Kim Maren Lompe, Gang Liu, Jan Peter Van Der Hoek
Abstract:
Microplastics (MPs) can undergo the photooxidation process under ultraviolet (UV) exposure, which determines their transformation and fate in environments. The presence of dissolved organic matter (DOM) can interact with MPs and take participate in the photo-degradation of MPs. As an important DOM component, dissolved black carbon (DBC), widely distributed in aquatic environments, can accelerate or inhibit the sunlight-driven photo-transformation of environmental pollutants. However, the role and underlying mechanism of DBC in the photooxidation of MPs are not clear. Herein, the DBC (< 0.45 µm) was extracted from wood biochar and fractionated by molecular weight (i.e., <3 KDa, 3 KDa−30 KDa, 30 KDa−0.45 µm). The effects of DBC chemical composition (i.e., molecular weight and chemical structure) in DBC-mediated photo-transformation of polystyrene (PS) MPs were investigated. The results showed that DBC initially inhibited the photo-degradation of MPs due to light shielding. Under UV exposure for 6−24 h, the presence of 5 mg/L DBC decreased the carbonyl index of MPs compared to the control. This inhibitory effect of DBC was found to decrease with increasing irradiation time. Notably, DBC initially decreased but then increased the hydroxyl index with aging time, suggesting that the role of DBC may shift from inhibition to acceleration. In terms of the different DBC fractions, the results showed that the smallest fraction of DBC (<3 KDa) significantly accelerated the photooxidation of PS MPs since it acted as reactive oxygen species (ROS) generators, especially in promoting the production of ¹O₂ and ³DBC* and •OH. With the increase in molecular weight, the acceleration effect of DBC on the degradation of MPs was decreased due to the increase of light shielding and possible decrease of photosensitization ability. This study thoroughly investigated the critical role of DBC chemical composition in the photooxidation process, which helps to assess the duration of aging and transformation of MPs during long-term weathering in natural waters.Keywords: microplastics, photo-degradation, dissolved black carbon, molecular weight, photosensitization
Procedia PDF Downloads 7615205 The Collaboration between Resident and Non-resident Patent Applicants as a Strategy to Accelerate Technological Advance in Developing Nations
Authors: Hugo Rodríguez
Abstract:
Migrations of researchers, scientists, and inventors are a widespread phenomenon in modern times. In some cases, migrants stay linked to research groups in their countries of origin, either out of their own conviction or because of government policies. We examine different linear models of technological development (using the Ordinary Least Squares (OLS) technique) in eight selected countries and find that the collaborations between resident and nonresident patent applicants correlate with different levels of performance of the technological policies in three different scenarios. Therefore, the reinforcement of that link must be considered a powerful tool for technological development.Keywords: development, collaboration, patents, technology
Procedia PDF Downloads 12715204 Removal of Problematic Organic Compounds from Water and Wastewater Using the Arvia™ Process
Authors: Akmez Nabeerasool, Michaelis Massaros, Nigel Brown, David Sanderson, David Parocki, Charlotte Thompson, Mike Lodge, Mikael Khan
Abstract:
The provision of clean and safe drinking water is of paramount importance and is a basic human need. Water scarcity coupled with tightening of regulations and the inability of current treatment technologies to deal with emerging contaminants and Pharmaceuticals and personal care products means that alternative treatment technologies that are viable and cost effective are required in order to meet demand and regulations for clean water supplies. Logistically, the application of water treatment in rural areas presents unique challenges due to the decentralisation of abstraction points arising from low population density and the resultant lack of infrastructure as well as the need to treat water at the site of use. This makes it costly to centralise treatment facilities and hence provide potable water direct to the consumer. Furthermore, across the UK there are segments of the population that rely on a private water supply which means that the owner or user(s) of these supplies, which can serve one household to hundreds, are responsible for the maintenance. The treatment of these private water supply falls on the private owners, and it is imperative that a chemical free technological solution that can operate unattended and does not produce any waste is employed. Arvia’s patented advanced oxidation technology combines the advantages of adsorption and electrochemical regeneration within a single unit; the Organics Destruction Cell (ODC). The ODC uniquely uses a combination of adsorption and electrochemical regeneration to destroy organics. Key to this innovative process is an alternative approach to adsorption. The conventional approach is to use high capacity adsorbents (e.g. activated carbons with high porosities and surface areas) that are excellent adsorbents, but require complex and costly regeneration. Arvia’s technology uses a patent protected adsorbent, Nyex™, which is a non-porous, highly conductive, graphite based adsorbent material that enables it to act as both the adsorbent and as a 3D electrode. Adsorbed organics are oxidised and the surface of the Nyex™ is regenerated in-situ for further adsorption without interruption or replacement. Treated water flows from the bottom of the cell where it can either be re-used or safely discharged. Arvia™ Technology Ltd. has trialled the application of its tertiary water treatment technology in treating reservoir water abstracted near Glasgow, Scotland, with promising results. Several other pilot plants have also been successfully deployed at various locations in the UK showing the suitability and effectiveness of the technology in removing recalcitrant organics (including pharmaceuticals, steroids and hormones), COD and colour.Keywords: Arvia™ process, adsorption, water treatment, electrochemical oxidation
Procedia PDF Downloads 26215203 Inhibition Effect of Natural Junipers Extract towards Steel Corrosion in HCl Solution
Authors: L. Bammou, M. Belkhaouda R. Salghi, L. Bazzi, B. Hammouti
Abstract:
Steel and steel-based alloys of different grades steel are extensively used in numerous applications where acid solutions are widely applied such as industrial acid pickling, industrial acid cleaning and oil-well acidizing. The use of chemical inhibitors is one of the most practical methods for the protection against corrosion in acidic media. Most of the excellent acid inhibitors are organic compounds containing nitrogen, oxygen, phosphorus and sulphur. The use of non-toxic inhibitors called green or eco-friendly environmental inhibitors is one of the solutions possible to prevent the corrosion of the material. These advantages have incited us to draw a large part of program of our laboratory to examine natural substances as corrosion inhibitors such as: prickly pear seed oil, Argan oil, Argan extract, Fennel oil, Rosemary oil, Thymus oil, Lavender oil, Jojoba oil, Pennyroyal Mint oil, and Artemisia. In the present work, we investigate the corrosion inhibition of steel in 1 M HCl by junipers extract using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. The result obtained of junipers extract (JE) shows excellent inhibition properties for the corrosion of C38 steel in 1M HCl at 298K, and the inhibition efficiency increases with increasing of the JE concentration. The inhibitor efficiencies determined by weight loss, Tafel polarisation and EIS methods are in reasonable agreement. Based on the polarisation results, the investigated junipers extract can be classified as mixed inhibitor. The calculated structural parameters show increase of the obtained Rct values and decrease of the capacitance, Cdl, with JE concentration increase. It is suggested to attribute this to the increase of the thickness of the adsorption layer at steel surface. The adsorption model obeys to the Langmuir adsorption isotherm. The adsorption process is a spontaneous and exothermic process.Keywords: corrosion inhibition, steel, friendly inhibitors, Tafel polarisation
Procedia PDF Downloads 51915202 Synthesis of Methanol through Photocatalytic Conversion of CO₂: A Green Chemistry Approach
Authors: Sankha Chakrabortty, Biswajit Ruj, Parimal Pal
Abstract:
Methanol is one of the most important chemical products and intermediates. It can be used as a solvent, intermediate or raw material for a number of higher valued products, fuels or additives. From the last one decay, the total global demand of methanol has increased drastically which forces the scientists to produce a large amount of methanol from a renewable source to meet the global demand with a sustainable way. Different types of non-renewable based raw materials have been used for the synthesis of methanol on a large scale which makes the process unsustainable. In this circumstances, photocatalytic conversion of CO₂ into methanol under solar/UV excitation becomes a viable approach to give a sustainable production approach which not only meets the environmental crisis by recycling CO₂ to fuels but also reduces CO₂ amount from the atmosphere. Development of such sustainable production approach for CO₂ conversion into methanol still remains a major challenge in the current research comparing with conventional energy expensive processes. In this backdrop, the development of environmentally friendly materials, like photocatalyst has taken a great perspective for methanol synthesis. Scientists in this field are always concerned about finding an improved photocatalyst to enhance the photocatalytic performance. Graphene-based hybrid and composite materials with improved properties could be a better nanomaterial for the selective conversion of CO₂ to methanol under visible light (solar energy) or UV light. The present invention relates to synthesis an improved heterogeneous graphene-based photocatalyst with improved catalytic activity and surface area. Graphene with enhanced surface area is used as coupled material of copper-loaded titanium oxide to improve the electron capture and transport properties which substantially increase the photoinduced charge transfer and extend the lifetime of photogenerated charge carriers. A fast reduction method through H₂ purging has been adopted to synthesis improved graphene whereas ultrasonication based sol-gel method has been applied for the preparation of graphene coupled copper loaded titanium oxide with some enhanced properties. Prepared photocatalysts were exhaustively characterized using different characterization techniques. Effects of catalyst dose, CO₂ flow rate, reaction temperature and stirring time on the efficacy of the system in terms of methanol yield and productivity have been studied in the present study. The study shown that the newly synthesized photocatalyst with an enhanced surface resulting in a sustained productivity and yield of methanol 0.14 g/Lh, and 0.04 g/gcat respectively, after 3 h of illumination under UV (250W) at an optimum catalyst dosage of 10 g/L having 1:2:3 (Graphene: TiO₂: Cu) weight ratio.Keywords: renewable energy, CO₂ capture, photocatalytic conversion, methanol
Procedia PDF Downloads 10715201 Conceptual Model for Logistics Information System
Authors: Ana María Rojas Chaparro, Cristian Camilo Sarmiento Chaves
Abstract:
Given the growing importance of logistics as a discipline for efficient management of materials flow and information, the adoption of tools that permit to create facilities in making decisions based on a global perspective of the system studied has been essential. The article shows how from a concepts-based model is possible to organize and represent in appropriate way the reality, showing accurate and timely information, features that make this kind of models an ideal component to support an information system, recognizing that information as relevant to establish particularities that allow get a better performance about the evaluated sector.Keywords: system, information, conceptual model, logistics
Procedia PDF Downloads 49515200 From Indigeneity to Urbanity: A Performative Study of Indian Saang (Folk Play) Tradition
Authors: Shiv Kumar
Abstract:
In the shifting scenario of postmodern age that foregrounds the multiplicity of meanings and discourses, the present research article seeks to investigate various paradigm shift of contemporary performances concerning Haryanvi Saangs, so-called folk plays, which are being performed widely in the regional territory of Haryana, a northern state of India. Folk arts cannot be studied efficiently by using the tools of literary criticism because it differs from the literature in many aspects. One of the most essential differences is that literary works invariably have an author. Folk works, on the contrary, never have an author. The situation is quite clear: either we acknowledge the presence of folk art as a phenomenon in the social and cultural history of people, or we do not acknowledge it and argue it is a poetical or art of fiction. This paper is an effort to understand the performative tradition of Saang which is traditionally known as Saang, Swang or Svang became a popular source for instruction and entertainment in the region and neighbouring states. Scholars and critics have long been debating about the origin of the word swang/svang/saang and their relationship to the Sanskrit word –Sangit, which means singing and music. But in the cultural context of Haryana, the word Saang means ‘to impersonate’ or ‘to imitate’ or ‘to copy someone or something’. The stories they portray are derived for the most part from the same myths, tales, epics and from the lives of Indian religious and folk heroes. Literally, the use of poetic sense, the implication of prose style and elaborate figurative technique are worthwhile to compile the productivity of a performance. All use music and song as an integral part of the performance so that it is also appropriate to call them folk opera. These folk plays are performed strictly by aboriginal people in the state. These people, sometimes denominated as Saangi, possess a culture distinct from the rest of Indian folk performances. The concerned form is also known with various other names like Manch, Khayal, Opera, Nautanki. The group of such folk plays can be seen as a dynamic activity and performed in the open space of the theatre. Nowadays, producers contributed greatly in order to create a rapidly growing musical outlet for budding new style of folk presentation and give rise to the electronic focus genre utilizing many musicians and performers who had to become precursors of the folk tradition in the region. Moreover, the paper proposes to examine available sources relative to this article, and it is believed to draw some different conclusions. For instance, to be a spectator of ongoing performances will contribute to providing enough guidance to move forward on this root. In this connection, the paper focuses critically upon the major performative aspects of Haryanvi Saang in relation to several inquiries such as the study of these plays in the context of Indian literary scenario, gender visualization and their dramatic representation, a song-music tradition in folk creativity and development of Haryanvi dramatic art in the contemporary socio-political background.Keywords: folk play, indigenous, performance, Saang, tradition
Procedia PDF Downloads 15515199 Acculturation of Iranian Students in Europe
Authors: Shirin Sadat Ahmadi
Abstract:
The number of people, particularly university students, migrating from Iran and applying for American and European universities has been rising during recent years. Different people may have various reasons and goals for migration, but one of the common issues among all these people is the cultural challenges they experience when living in the adopted society. Immigrants usually confront obstacles during the Intercultural transition and adaption process. Different variables such as age, religion, gender, education, knowing the spoken language in destination country, financial condition, interactions with natives, and using social media can affect the cultural challenges people face after migration and how they conquer issues appearing due to intercultural differences and conflicts. In this research we have interviewed a sample consisted of 15 Iranian students living and studying abroad found by using snowball sampling technique via video call to realize what cultural challenges they have experienced in the new society, how the mentioned variables above eased these challenges or made them harder and what approaches and solutions they adopted to adjust themselves to the new society and its cultural dimensions. Based on John Berry's acculturation theory of migrant-host relationship, we have classified these 15 people in five different categories: Assimilation, Separation, Marginalization, and Integration. In addition we have considered Y.Y. Kim's communication-based theory of cross-cultural adaption to explain how communications helped migrant populations in adaption process. Based on the findings of this study, 12 of 15 interviewed members of the study used the integration strategy to adapt to the new cultural environment, 3 of them used the assimilation strategy, and none of them used marginalization or separation strategies. Communicating with natives, knowing the language, and education were the factors that helped all the interviewed members of the sample to overcome the difficulties of intercultural transition.Keywords: acculturation, culture, intercultural transition, migration
Procedia PDF Downloads 6315198 Change in Self-Reported Personality in Students of Acting
Authors: Nemanja D. Kidzin
Abstract:
The field of personality change has recently garnered increased attention, while the psychology of acting has remained relatively understudied. This research tried to contribute to the both research field by investigating whether the process of acting can lead to personality changes in acting students and, if so, in what manner. It was hypothesized that significant differences would be observed in self-reported personality traits of acting students between the beginning and end of their role preparation. The study also examined potential moderator variables, including the reported personality traits of the roles portrayed by the students, empathy, disintegration, and years of formal acting education. The sample comprised 47 students of acting from the Faculty of Dramatic Arts (first to fourth-year) and the Faculty of Modern Arts (first-year students only). The research involved two waves of testing, conducted at the beginning (T1) and end (T2) of the semester. Personality traits (measured using the HEXACO-60 self-report version), empathy (measured using the Questionnaire of Cognitive and Affective Empathy, QCAE), and disintegration (measured using the DELTA9, 10-item version) were assessed at both T1 and T2, while the personality of the role (measured using the HEXACO-60 observer version) was assessed at T2. Repeated-measures t-tests revealed significant differences in emotionality and conscientiousness between T1 and T2. Additionally, an index of absolute personality change was significantly different from 0 for all traits, indicating personality change. The average test-retest correlation for HEXACO traits was 0.57, lower than that proposed in similar research. However, the personality of the role, empathy, and disintegration did not explain the changes in students' personality traits as moderator variables. The magnitude of personality change was highest among fourth-year students, with no significant differences observed among the remaining three years of study. Overall, the findings suggest the presence of personality changes or trait variability in acting students. However, these changes cannot be conclusively attributed to the process of role preparation. Further research with more stringent methodologies is needed to better understand the role of acting in personality change.Keywords: personality change, psychology of acting, empathy, disintegraton
Procedia PDF Downloads 6815197 Gassing Tendency of Natural Ester Based Transformer oils: Low Alkane Generation in Stray Gassing Behaviour
Authors: Thummalapalli CSM Gupta, Banti Sidhiwala
Abstract:
Mineral oils of naphthenic and paraffinic type have been traditionally been used as insulating liquids in the transformer applications to protect the solid insulation from moisture and ensures effective heat transfer/cooling. The performance of these type of oils have been proven in the field over many decades and the condition monitoring and diagnosis of transformer performance have been successfully monitored through oil properties and dissolved gas analysis methods successfully. Different type of gases representing various types of faults due to components or operating conditions effectively. While large amount of data base has been generated in the industry on dissolved gas analysis for mineral oil based transformer oils and various models for predicting the fault and analysis, oil specifications and standards have also been modified to include stray gassing limits which cover the low temperature faults and becomes an effective preventative maintenance tool that can benefit greatly to know the reasons for the breakdown of electrical insulating materials and related components. Natural esters have seen a rise in popularity in recent years due to their "green" credentials. Some of its benefits include biodegradability, a higher fire point, improvement in load capability of transformer and improved solid insulation life than mineral oils. However, the Stray gases evolution like hydrogen and hydrocarbons like methane (CH4) and ethane (C2H6) show very high values which are much higher than the limits of mineral oil standards. Though the standards for these type esters are yet to be evolved, the higher values of hydrocarbon gases that are available in the market is of concern which might be interpreted as a fault in transformer operation. The current paper focuses on developing a natural ester based transformer oil which shows very levels of stray gassing by standard test methods show much lower values compared to the products available currently and experimental results on various test conditions and the underlying mechanism explained.Keywords: biodegadability, fire point, dissolved gassing analysis, stray gassing
Procedia PDF Downloads 9415196 Heteroatom Doped Binary Metal Oxide Modified Carbon as a Bifunctional Electrocatalysts for all Vanadium Redox Flow Battery
Authors: Anteneh Wodaje Bayeh, Daniel Manaye Kabtamu, Chen-Hao Wang
Abstract:
As one of the most promising electrochemical energy storage systems, vanadium redox flow batteries (VRFBs) have received increasing attention owing to their attractive features for largescale storage applications. However, their high production cost and relatively low energy efficiency still limit their feasibility. For practical implementation, it is of great interest to improve their efficiency and reduce their cost. One of the key components of VRFBs that can greatly influence the efficiency and final cost is the electrode, which provide the reactions sites for redox couples (VO²⁺/VO₂ + and V²⁺/V³⁺). Carbon-based materials are considered to be the most feasible electrode materials in the VRFB because of their excellent potential in terms of operation range, good permeability, large surface area, and reasonable cost. However, owing to limited electrochemical activity and reversibility and poor wettability due to its hydrophobic properties, the performance of the cell employing carbon-based electrodes remained limited. To address the challenges, we synthesized heteroatom-doped bimetallic oxide grown on the surface of carbon through the one-step approach. When applied to VRFBs, the prepared electrode exhibits significant electrocatalytic effect toward the VO²⁺/VO₂ + and V³⁺/V²⁺ redox reaction compared with that of pristine carbon. It is found that the presence of heteroatom on metal oxide promotes the absorption of vanadium ions. The controlled morphology of bimetallic metal oxide also exposes more active sites for the redox reaction of vanadium ions. Hence, the prepared electrode displays the best electrochemical performance with energy and voltage efficiencies of 74.8% and 78.9%, respectively, which is much higher than those of 59.8% and 63.2% obtained from the pristine carbon at high current density. Moreover, the electrode exhibit durability and stability in an acidic electrolyte during long-term operation for 1000 cycles at the higher current density.Keywords: VRFB, VO²⁺/VO₂ + and V³⁺/V²⁺ redox couples, graphite felt, heteroatom-doping
Procedia PDF Downloads 9515195 Numerical Evolution Methods of Rational Form for Diffusion Equations
Authors: Said Algarni
Abstract:
The purpose of this study was to investigate selected numerical methods that demonstrate good performance in solving PDEs. We adapted alternative method that involve rational polynomials. Padé time stepping (PTS) method, which is highly stable for the purposes of the present application and is associated with lower computational costs, was applied. Furthermore, PTS was modified for our study which focused on diffusion equations. Numerical runs were conducted to obtain the optimal local error control threshold.Keywords: Padé time stepping, finite difference, reaction diffusion equation, PDEs
Procedia PDF Downloads 29615194 Screening of Factors Affecting the Enzymatic Hydrolysis of Empty Fruit Bunches in Aqueous Ionic Liquid and Locally Produced Cellulase System
Authors: Md. Z. Alam, Amal A. Elgharbawy, Muhammad Moniruzzaman, Nassereldeen A. Kabbashi, Parveen Jamal
Abstract:
The enzymatic hydrolysis of lignocellulosic biomass is one of the obstacles in the process of sugar production, due to the presence of lignin that protects the cellulose molecules against cellulases. Although the pretreatment of lignocellulose in ionic liquid (IL) system has been receiving a lot of interest; however, it requires IL removal with an anti-solvent in order to proceed with the enzymatic hydrolysis. At this point, introducing a compatible cellulase enzyme seems more efficient in this process. A cellulase enzyme that was produced by Trichoderma reesei on palm kernel cake (PKC) exhibited a promising stability in several ILs. The enzyme called PKC-Cel was tested for its optimum pH and temperature as well as its molecular weight. One among evaluated ILs, 1,3-diethylimidazolium dimethyl phosphate [DEMIM] DMP was applied in this study. Evaluation of six factors was executed in Stat-Ease Design Expert V.9, definitive screening design, which are IL/ buffer ratio, temperature, hydrolysis retention time, biomass loading, cellulase loading and empty fruit bunches (EFB) particle size. According to the obtained data, IL-enzyme system shows the highest sugar concentration at 70 °C, 27 hours, 10% IL-buffer, 35% biomass loading, 60 Units/g cellulase and 200 μm particle size. As concluded from the obtained data, not only the PKC-Cel was stable in the presence of the IL, also it was actually stable at a higher temperature than its optimum one. The reducing sugar obtained was 53.468±4.58 g/L which was equivalent to 0.3055 g reducing sugar/g EFB. This approach opens an insight for more studies in order to understand the actual effect of ILs on cellulases and their interactions in the aqueous system. It could also benefit in an efficient production of bioethanol from lignocellulosic biomass.Keywords: cellulase, hydrolysis, lignocellulose, pretreatment
Procedia PDF Downloads 36415193 Static Application Security Testing Approach for Non-Standard Smart Contracts
Authors: Antonio Horta, Renato Marinho, Raimir Holanda
Abstract:
Considered as an evolution of the Blockchain, the Ethereum platform, besides allowing transactions of its cryptocurrency named Ether, it allows the programming of decentralised applications (DApps) and smart contracts. However, this functionality into blockchains has raised other types of threats, and the exploitation of smart contracts vulnerabilities has taken companies to experience big losses. This research intends to figure out the number of contracts that are under risk of being drained. Through a deep investigation, more than two hundred thousand smart contracts currently available in the Ethereum platform were scanned and estimated how much money is at risk. The experiment was based in a query run on Google Big Query in July 2022 and returned 50,707,133 contracts published on the Ethereum platform. After applying the filtering criteria, the experimentgot 430,584 smart contracts to download and analyse. The filtering criteria consisted of filtering out: ERC20 and ERC721 contracts, contracts without transactions, and contracts without balance. From this amount of 430,584 smart contracts selected, only 268,103 had source codes published on Etherscan, however, we discovered, using a hashing process, that there were contracts duplication. Removing the duplicated contracts, the process ended up with 20,417 source codes, which were analysed using the open source SAST tool smartbugswith oyente and securify algorithms. In the end, there was nearly $100,000 at risk of being drained from the potentially vulnerable smart contracts. It is important to note that the tools used in this study may generate false positives, which may interfere with the number of vulnerable contracts. To address this point, our next step in this research is to develop an application to test the contract in a parallel environment to verify the vulnerability. Finally, this study aims to alert users and companies about the risk on not properly creating and analysing their smart contracts before publishing them into the platform. As any other application, smart contracts are at risk of having vulnerabilities which, in this case, may result in direct financial losses.Keywords: blockchain, reentrancy, static application security testing, smart contracts
Procedia PDF Downloads 8615192 A Combinatorial Approach of Treatment for Landfill Leachate
Authors: Anusha Atmakuri, R. D. Tyagi, Patrick Drogui
Abstract:
Landfilling is the most familiar and easy way to dispose solid waste. Landfill is generally received via wastes from municipal near to a landfill. The waste collected is from commercial, industrial, and residential areas and many more. Landfill leachate (LFL) is formed when rainwater passes through the waste placed in landfills and consists of several dissolved organic materials, for instance, aquatic humic substances (AHS), volatile fatty acids (VFAs), heavy metals, inorganic macro components, and xenobiotic organic matters, highly toxic to the environment. These components of LFL put a load on it, hence it necessitates the treatment of LFL prior to its discharge into the environment. Various methods have been used to treat LFL over the years, such as physical, chemical, biological, physicochemical, electrical, and advanced oxidation methods. This study focuses on the combination of biological and electrochemical methods- extracellular polymeric substances and electrocoagulation(EC). The coupling of electro-coagulation process with extracellular polymeric substances (EPS) (as flocculant) as pre and\or post treatment strategy provides efficient and economical process for the decontamination of landfill leachate contaminated with suspended matter, metals (e.g., Fe, Mn) and ammonical nitrogen. Electro-coagulation and EPS mediated coagulation approach could be an economically viable for the treatment of landfill leachate, along with possessing several other advantages over several other methods. This study utilised waste substrates such as activated sludge, crude glycerol and waste cooking oil for the production of EPS using fermentation technology. A comparison of different scenarios for the treatment of landfill leachate is presented- such as using EPS alone as bioflocculant, EPS and EC with EPS being the 1st stage, and EPS and EC with EC being the 1st stage. The work establishes the use of crude EPS as a bioflocculant for the treatment of landfill leachate and wastewater from a site near a landfill, along with EC being successful in removal of some major pollutants such as COD, turbidity, total suspended solids. A combination of these two methods is to be explored more for the complete removal of all pollutants from landfill leachate.Keywords: landfill leachate, extracellular polymeric substances, electrocoagulation, bioflocculant.
Procedia PDF Downloads 8615191 Easy Way of Optimal Process-Storage Network Design
Authors: Gyeongbeom Yi
Abstract:
The purpose of this study is to introduce the analytic solution for determining the optimal capacity (lot-size) of a multiproduct, multistage production and inventory system to meet the finished product demand. Reasonable decision-making about the capacity of processes and storage units is an important subject for industry. The industrial solution for this subject is to use the classical economic lot sizing method, EOQ/EPQ (Economic Order Quantity/Economic Production Quantity) model, incorporated with practical experience. However, the unrealistic material flow assumption of the EOQ/EPQ model is not suitable for chemical plant design with highly interlinked processes and storage units. This study overcomes the limitation of the classical lot sizing method developed on the basis of the single product and single stage assumption. The superstructure of the plant considered consists of a network of serially and/or parallelly interlinked processes and storage units. The processes involve chemical reactions with multiple feedstock materials and multiple products as well as mixing, splitting or transportation of materials. The objective function for optimization is minimizing the total cost composed of setup and inventory holding costs as well as the capital costs of constructing processes and storage units. A novel production and inventory analysis method, PSW (Periodic Square Wave) model, is applied. The advantage of the PSW model comes from the fact that the model provides a set of simple analytic solutions in spite of a realistic description of the material flow between processes and storage units. The resulting simple analytic solution can greatly enhance the proper and quick investment decision for plant design and operation problem confronted in diverse economic situations.Keywords: analytic solution, optimal design, process-storage network
Procedia PDF Downloads 33015190 Developing a Framework for Designing Digital Assessments for Middle-school Aged Deaf or Hard of Hearing Students in the United States
Authors: Alexis Polanco Jr, Tsai Lu Liu
Abstract:
Research on digital assessment for deaf and hard of hearing (DHH) students is negligible. Part of this stems from the DHH assessment design existing at the intersection of the emergent disciplines of usability, accessibility, and child-computer interaction (CCI). While these disciplines have some prevailing guidelines —e.g. in user experience design (UXD), there is Jacob Nielsen’s 10 Usability Heuristics (Nielsen-10); for accessibility, there are the Web Content Accessibility Guidelines (WCAG) & the Principles of Universal Design (PUD)— this research was unable to uncover a unified set of guidelines. Given that digital assessments have lasting implications for the funding and shaping of U.S. school districts, it is vital that cross-disciplinary guidelines emerge. As a result, this research seeks to provide a framework by which these disciplines can share knowledge. The framework entails a process of asking subject-matter experts (SMEs) and design & development professionals to self-describe their fields of expertise, how their work might serve DHH students, and to expose any incongruence between their ideal process and what is permissible at their workplace. This research used two rounds of mixed methods. The first round consisted of structured interviews with SMEs in usability, accessibility, CCI, and DHH education. These practitioners were not designers by trade but were revealed to use designerly work processes. In addition to asking these SMEs about their field of expertise, work process, etc., these SMEs were asked to comment about whether they believed Nielsen-10 and/or PUD were sufficient for designing products for middle-school DHH students. This first round of interviews revealed that Nielsen-10 and PUD were, at best, a starting point for creating middle-school DHH design guidelines or, at worst insufficient. The second round of interviews followed a semi-structured interview methodology. The SMEs who were interviewed in the first round were asked open-ended follow-up questions about their semantic understanding of guidelines— going from the most general sense down to the level of design guidelines for DHH middle school students. Designers and developers who were never interviewed previously were asked the same questions that the SMEs had been asked across both rounds of interviews. In terms of the research goals: it was confirmed that the design of digital assessments for DHH students is inherently cross-disciplinary. Unexpectedly, 1) guidelines did not emerge from the interviews conducted in this study, and 2) the principles of Nielsen-10 and PUD were deemed to be less relevant than expected. Given the prevalence of Nielsen-10 in UXD curricula across academia and certificate programs, this poses a risk to the efficacy of DHH assessments designed by UX designers. Furthermore, the following findings emerged: A) deep collaboration between the disciplines of usability, accessibility, and CCI is low to non-existent; B) there are no universally agreed-upon guidelines for designing digital assessments for DHH middle school students; C) these disciplines are structured academically and professionally in such a way that practitioners may not know to reach out to other disciplines. For example, accessibility teams at large organizations do not have designers and accessibility specialists on the same team.Keywords: deaf, hard of hearing, design, guidelines, education, assessment
Procedia PDF Downloads 66