Search results for: anxiety reduction
4703 Mathematical Modeling of Thin Layer Drying Behavior of Bhimkol (Musa balbisiana) Pulp
Authors: Ritesh Watharkar, Sourabh Chakraborty, Brijesh Srivastava
Abstract:
Reduction of water from the fruits and vegetables using different drying techniques is widely employed to prolong the shelf life of these food commodities. Heat transfer occurs inside the sample by conduction and mass transfer takes place by diffusion in accordance with temperature and moisture concentration gradient respectively during drying. This study was undertaken to study and model the thin layer drying behavior of Bhimkol pulp. The drying was conducted in a tray drier at 500c temperature with 5, 10 and 15 % concentrations of added maltodextrin. The drying experiments were performed at 5mm thickness of the thin layer and the constant air velocity of 0.5 m/s.Drying data were fitted to different thin layer drying models found in the literature. Comparison of fitted models was based on highest R2(0.9917), lowest RMSE (0.03201), and lowest SSE (0.01537) revealed Middle equation as the best-fitted model for thin layer drying with 10% concentration of maltodextrin. The effective diffusivity was estimated based on the solution of Fick’s law of diffusion which is found in the range of 3.0396 x10-09 to 5.0661 x 10-09. There was a reduction in drying time with the addition of maltodextrin as compare to the raw pulp.Keywords: Bhimkol, diffusivity, maltodextrine, Midilli model
Procedia PDF Downloads 2114702 Construction of QSAR Models to Predict Potency on a Series of substituted Imidazole Derivatives as Anti-fungal Agents
Authors: Sara El Mansouria Beghdadi
Abstract:
Quantitative structure–activity relationship (QSAR) modelling is one of the main computer tools used in medicinal chemistry. Over the past two decades, the incidence of fungal infections has increased due to the development of resistance. In this study, the QSAR was performed on a series of esters of 2-carboxamido-3-(1H-imidazole-1-yl) propanoic acid derivatives. These compounds have showed moderate and very good antifungal activity. The multiple linear regression (MLR) was used to generate the linear 2d-QSAR models. The dataset consists of 115 compounds with their antifungal activity (log MIC) against «Candida albicans» (ATCC SC5314). Descriptors were calculated, and different models were generated using Chemoffice, Avogadro, GaussView software. The selected model was validated. The study suggests that the increase in lipophilicity and the reduction in the electronic character of the substituent in R1, as well as the reduction in the steric hindrance of the substituent in R2 and its aromatic character, supporting the potentiation of the antifungal effect. The results of QSAR could help scientists to propose new compounds with higher antifungal activities intended for immunocompromised patients susceptible to multi-resistant nosocomial infections.Keywords: quantitative structure–activity relationship, imidazole, antifungal, candida albicans (ATCC SC5314)
Procedia PDF Downloads 844701 Predicting Food Waste and Losses Reduction for Fresh Products in Modified Atmosphere Packaging
Authors: Matar Celine, Gaucel Sebastien, Gontard Nathalie, Guilbert Stephane, Guillard Valerie
Abstract:
To increase the very short shelf life of fresh fruits and vegetable, Modified Atmosphere Packaging (MAP) allows an optimal atmosphere composition to be maintained around the product and thus prevent its decay. This technology relies on the modification of internal packaging atmosphere due to equilibrium between production/consumption of gases by the respiring product and gas permeation through the packaging material. While, to the best of our knowledge, benefit of MAP for fresh fruits and vegetable has been widely demonstrated in the literature, its effect on shelf life increase has never been quantified and formalized in a clear and simple manner leading difficult to anticipate its economic and environmental benefit, notably through the decrease of food losses. Mathematical modelling of mass transfers in the food/packaging system is the basis for a better design and dimensioning of the food packaging system. But up to now, existing models did not permit to estimate food quality nor shelf life gain reached by using MAP. However, shelf life prediction is an indispensable prerequisite for quantifying the effect of MAP on food losses reduction. The objective of this work is to propose an innovative approach to predict shelf life of MAP food product and then to link it to a reduction of food losses and wastes. In this purpose, a ‘Virtual MAP modeling tool’ was developed by coupling a new predictive deterioration model (based on visual surface prediction of deterioration encompassing colour, texture and spoilage development) with models of the literature for respiration and permeation. A major input of this modelling tool is the maximal percentage of deterioration (MAD) which was assessed from dedicated consumers’ studies. Strawberries of the variety Charlotte were selected as the model food for its high perishability, high respiration rate; 50-100 ml CO₂/h/kg produced at 20°C, allowing it to be a good representative of challenging post-harvest storage. A value of 13% was determined as a limit of acceptability for the consumers, permitting to define products’ shelf life. The ‘Virtual MAP modeling tool’ was validated in isothermal conditions (5, 10 and 20°C) and in dynamic temperature conditions mimicking commercial post-harvest storage of strawberries. RMSE values were systematically lower than 3% for respectively, O₂, CO₂ and deterioration profiles as a function of time confirming the goodness of model fitting. For the investigated temperature profile, a shelf life gain of 0.33 days was obtained in MAP compared to the conventional storage situation (no MAP condition). Shelf life gain of more than 1 day could be obtained for optimized post-harvest conditions as numerically investigated. Such shelf life gain permitted to anticipate a significant reduction of food losses at the distribution and consumer steps. This food losses' reduction as a function of shelf life gain has been quantified using a dedicated mathematical equation that has been developed for this purpose.Keywords: food losses and wastes, modified atmosphere packaging, mathematical modeling, shelf life prediction
Procedia PDF Downloads 1824700 Exploring Fear in Moral Life: Implications for Education
Authors: Liz Jackson
Abstract:
Fear is usually considered as a basic emotion. In society, it is normally cast as undesirable, but also as partly unavoidable. Fear can be said to underlie courage or be required for courage, or it can be understood as its foil. Fear is not normally promoted (intentionally) in education, or treated as something that should be cultivated in schools or in society. However, fear is a basic, to some extent unavoidable emotion, related to truly fearsome things in the world. Fear is also understood to underlie anxiety. Fear is seen as basically disruptive to education, while from a psychological view it is an ordinary state. that cannot be avoided altogether. Despite calls to diminish this negative and mixed feeling in education and society, it can be regarded as socially and personally valuable, and psychologically functional in some situations. One should not take for granted the goodness of fear. However, it can be productive to explore its moral worth, and uses and abuses. Such uncomfortable feelings and experiences can be cultivated and explored via educational and other societal influences, in ways that can benefit a person and their relations with others in the world, while they can also be detrimental.Keywords: virtue ethics, philosophy of education, moral philosophy, fear
Procedia PDF Downloads 1424699 Field Study of Chlorinated Aliphatic Hydrocarbons Degradation in Contaminated Groundwater via Micron Zero-Valent Iron Coupled with Biostimulation
Authors: Naijin Wu, Peizhong Li, Haijian Wang, Wenxia Wei, Yun Song
Abstract:
Chlorinated aliphatic hydrocarbons (CAHs) pollution poses a severe threat to human health and is persistent in groundwater. Although chemical reduction or bioremediation is effective, it is still hard to achieve their complete and rapid dechlorination. Recently, the combination of zero-valent iron and biostimulation has been considered to be one of the most promising strategies, but field studies of this technology are scarce. In a typical site contaminated by various types of CAHs, basic physicochemical parameters of groundwater, CAHs and their product concentrations, and microbial abundance and diversity were monitored after a remediation slurry containing both micron zero-valent iron (mZVI) and biostimulation components were directly injected into the aquifer. Results showed that groundwater could form and keep low oxidation-reduction potential (ORP), a neutral pH, and anoxic conditions after different degrees of fluctuations, which was benefit for the reductive dechlorination of CAHs. The injection also caused an obvious increase in the total organic carbon (TOC) concentration and sulfate reduction. After 253 days post-injection, the mean concentration of total chlorinated ethylene (CEE) from two monitoring wells decreased from 304 μg/L to 8 μg/L, and total chlorinated ethane (CEA) decreased from 548 μg/L to 108 μg/L. Occurrence of chloroethane (CA) suggested that hydrogenolysis dechlorination was one of the main degradation pathways for CEA, and also hints that biological dechlorination was activated. A significant increase of ethylene at day 67 post-injection indicated that dechlorination was complete. Additionally, the total bacterial counts increased by 2-3 orders of magnitude after 253 days post-injection. And the microbial species richness decreased and gradually changed to anaerobic/fermentative bacteria. The relative abundance of potential degradation bacteria increased corresponding to the degradation of CAHs. This work demonstrates that mZVI and biostimulation can be combined to achieve the efficient removal of various CAHs from contaminated groundwater sources.Keywords: chlorinated aliphatic hydrocarbons, groundwater, field study, zero-valent iron, biostimulation
Procedia PDF Downloads 1654698 The Prediction of Reflection Noise and Its Reduction by Shaped Noise Barriers
Authors: I. L. Kim, J. Y. Lee, A. K. Tekile
Abstract:
In consequence of the very high urbanization rate of Korea, the number of traffic noise damages in areas congested with population and facilities is steadily increasing. The current environmental noise levels data in major cities of the country show that the noise levels exceed the standards set for both day and night times. This research was about comparative analysis in search for optimal soundproof panel shape and design factor that can minimize sound reflection noise. In addition to the normal flat-type panel shape, the reflection noise reduction of swelling-type, combined swelling and curved-type, and screen-type were evaluated. The noise source model Nord 2000, which often provides abundant information compared to models for the similar purpose, was used in the study to determine the overall noise level. Based on vehicle categorization in Korea, the noise levels for varying frequency from different heights of the sound source (directivity heights of Harmonize model) have been calculated for simulation. Each simulation has been made using the ray-tracing method. The noise level has also been calculated using the noise prediction program called SoundPlan 7.2, for comparison. The noise level prediction was made at 15m (R1), 30 m (R2) and at middle of the road, 2m (R3) receiving the point. By designing the noise barriers by shape and running the prediction program by inserting the noise source on the 2nd lane to the noise barrier side, among the 6 lanes considered, the reflection noise slightly decreased or increased in all noise barriers. At R1, especially in the cases of the screen-type noise barriers, there was no reduction effect predicted in all conditions. However, the swelling-type showed a decrease of 0.7~1.2 dB at R1, performing the best reduction effect among the tested noise barriers. Compared to other forms of noise barriers, the swelling-type was thought to be the most suitable for reducing the reflection noise; however, since a slight increase was predicted at R2, further research based on a more sophisticated categorization of related design factors is necessary. Moreover, as swellings are difficult to produce and the size of the modules are smaller than other panels, it is challenging to install swelling-type noise barriers. If these problems are solved, its applicable region will not be limited to other types of noise barriers. Hence, when a swelling-type noise barrier is installed at a downtown region where the amount of traffic is increasing every day, it will both secure visibility through the transparent walls and diminish any noise pollution due to the reflection. Moreover, when decorated with shapes and design, noise barriers will achieve a visual attraction than a flat-type one and thus will alleviate any psychological hardships related to noise, other than the unique physical soundproofing functions of the soundproof panels.Keywords: reflection noise, shaped noise barriers, sound proof panel, traffic noise
Procedia PDF Downloads 5094697 Wind Load Reduction Effect of Exterior Porous Skin on Facade Performance
Authors: Ying-Chang Yu, Yuan-Lung Lo
Abstract:
Building envelope design is one of the most popular design fields of architectural profession in nowadays. The main design trend of such system is to highlight the designer's aesthetic intention from the outlook of building project. Due to the trend of current façade design, the building envelope contains more and more layers of components, such as double skin façade, photovoltaic panels, solar control system, or even ornamental components. These exterior components are designed for various functional purposes. Most researchers focus on how these exterior elements should be structurally sound secured. However, not many researchers consider these elements would help to improve the performance of façade system. When the exterior elements are deployed in large scale, it creates an additional layer outside of original façade system and acts like a porous interface which would interfere with the aerodynamic of façade surface in micro-scale. A standard façade performance consists with 'water penetration, air infiltration rate, operation force, and component deflection ratio', and these key performances are majorly driven by the 'Design Wind Load' coded in local regulation. A design wind load is usually determined by the maximum wind pressure which occurs on the surface due to the geometry or location of building in extreme conditions. This research was designed to identify the air damping phenomenon of micro turbulence caused by porous exterior layer leading to surface wind load reduction for improvement of façade system performance. A series of wind tunnel test on dynamic pressure sensor array covered by various scale of porous exterior skin was conducted to verify the effect of wind pressure reduction. The testing specimens were designed to simulate the typical building with two-meter extension offsetting from building surface. Multiple porous exterior skins were prepared to replicate various opening ratio of surface which may cause different level of damping effect. This research adopted 'Pitot static tube', 'Thermal anemometers', and 'Hot film probe' to collect the data of surface dynamic pressure behind porous skin. Turbulence and distributed resistance are the two main factors of aerodynamic which would reduce the actual wind pressure. From initiative observation, the reading of surface wind pressure was effectively reduced behind porous media. In such case, an actual building envelope system may be benefited by porous skin from the reduction of surface wind pressure, which may improve the performance of envelope system consequently.Keywords: multi-layer facade, porous media, facade performance, turbulence and distributed resistance, wind tunnel test
Procedia PDF Downloads 2174696 Psychological Contract Breach and Violation Relationships with Stress and Wellbeing
Authors: Fazeelat Duran, Darren Bishopp, Jessica Woodhams
Abstract:
Negative emotions resulting from the breach of perceived obligations by an employer is called the psychological contract violation. Employees perceiving breach and feelings of negative emotions result in adverse outcomes for both the employee and employer. This paper aims to identify the relationships between contract breach, violation, stress and wellbeing and investigate whether fairness and self-efficacy mediate the relationships. A mixed method approach was used to analyze the online-surveys and semi-structured interviews with the police officers. It was identified that the psychological contract violation predicts stress and job-related well-being. Fairness and self-efficacy were identified as significant mediators to understand the underlying mechanisms of association. Whilst, in the interviews social support was identified as a popular mediator. Practical implications for employers are discussed.Keywords: psychological contract violation and breach, stressors, depression, anxiety
Procedia PDF Downloads 2454695 The Language of Art: Examining Emotional Expression in Drawings of Internally Displaced Persons and Town Students Amid Conflict
Authors: Lugyi No
Abstract:
This research delves into how students from two different backgrounds in a conflict-affected area, one group being internally displaced (IDP) and the other residing in permanent homes, express their emotions through art. Two experiments were conducted involving guided drawing to understand their emotional experiences. In the first experiment, where no specific instructions were given, both groups mostly used dark and dull colors, which suggests feelings of sadness and anxiety. Positive emotions were rarely depicted. In the second experiment, students were asked to express their emotions and provide reasons for their drawings. Here, we observed distinct variations: IDP students leaned towards vibrant colors, reflecting resilience, while town students tended to use monochromatic shades, likely due to their experiences with conflict. This abstract highlights the differing emotional expressions of these groups and the influence of instructions on their artwork.Keywords: art therapy, conflict-affected areas, education in conflict zones, children's drawings
Procedia PDF Downloads 584694 Reduction of Aerodynamic Drag Using Vortex Generators
Authors: Siddharth Ojha, Varun Dua
Abstract:
Classified as one of the most important reasons of aerodynamic drag in the sedan automobiles is the fluid flow separation near the vehicle’s rear end. To retard the separation of flow, bump-shaped vortex generators are being tested for its implementation to the roof end of a sedan vehicle. Frequently used in the aircrafts to prevent the separation of fluid flow, vortex generators themselves produce drag, but they also substantially reduce drag by preventing flow separation at the downstream. The net effects of vortex generators can be calculated by summing the positive and negative impacts and effects. Since this effect depends on dimensions and geometry of vortex generators, those present on the vehicle roof are optimized for maximum efficiency and performance. The model was tested through ANSYS CFD analysis and modeling. The model was tested in the wind tunnel for observing it’s properties such as aerodynamic drag and flow separation and a major time lag was gained by employing vortex generators in the scaled model. Major conclusions which were recorded during the analysis were a substantial 24% reduction in the aerodynamic drag and 14% increase in the efficiency of the sedan automobile as the flow separation from the surface is delayed. This paper presents the results of optimization, the effect of vortex generators in the flow field and the mechanism by which these effects occur and are regulated.Keywords: aerodynamics, aerodynamic devices, body, computational fluid dynamics (CFD), flow visualization
Procedia PDF Downloads 2234693 Empirical Investigation of Bullwhip Effect with Sensitivity Analysis in Supply Chain
Authors: Shoaib Yousaf
Abstract:
The main purpose of this research is to the empirical investigation of the bullwhip effect under sensitivity analysis in the two-tier supply chain. The simulation modeling technique has been applied in this research as a research methodology to see the sensitivity analysis of the bullwhip effect in the rice industry of Pakistan. The research comprises two case studies that have been chosen as a sample. The results of this research have confirmed that reduction in production delay reduces the bullwhip effect, which conforms to the time compressing paradigm and the significance of the reduction in production delay to lessen demand amplification. The result of this research also indicates that by increasing the value of time to adjust inventory decreases the bullwhip effect. Furthermore, by decreasing the value of alpha increases the damping effect of the exponential smoother, it is not surprising that it also reduces the bullwhip effect. Moreover, by reducing the value of time to work in progress also reduces the bullwhip effect. This research will help practitioners and operation managers to reduces the major costs of their products in three ways. They can reduce their i) inventory levels, ii) better utilize their capacity and iii) improve their forecasting techniques. However, this study is based on two tier supply chain, while in reality the supply chain has got many tiers. Hence, future work will be extended across more than two-tier supply chains.Keywords: bullwhip effect, rice industry, supply chain dynamics, simulation, sensitivity analysis
Procedia PDF Downloads 1444692 Entrepreneurship as a Strategy for National Development and Attainment of Millennium Development Goals (MDGs)
Authors: Udokporo Emeka Leonard
Abstract:
The thrust of this paper is to examine how entrepreneurship can assist in the attainment of the first goal among the MDGs – eradication of extreme poverty and hunger in Nigeria. The paper discusses how national development can be driven through employment creation and wealth generation that can lead to reduction in widespread poverty so as to attain one crucial target, in fewer years. The task before Nigeria is certainly a herculean one; it is, in fact a race against time. However, in view of the clear and present danger that the increasing rate of poverty portends for our democracy and our nation, is a race we must; for it is a time bomb on our hands. The paper has been structured into sections; with the introduction as section one. Section two discusses the concept of entrepreneurship; Section three examines the link between entrepreneurship and economic development, while section four examines the challenges facing entrepreneurship in Nigeria. In section five, measures and recommendations to boost entrepreneurship that can drive economic development that translates into poverty reduction and employment creation in Nigeria are suggested. This work is a literature review with some understanding of current trends and situations. It outlines some of the difficulties facing entrepreneurship in Nigeria as the operating environment, inadequate understanding and skewed incentive. It also makes recommendations on possible ways to significantly reduce poverty in 2015.Keywords: development, entrepreneur, Nigeria, poverty
Procedia PDF Downloads 2874691 Effect of Halo Protection Device on the Aerodynamic Performance of Formula Racecar
Authors: Mark Lin, Periklis Papadopoulos
Abstract:
This paper explores the aerodynamics of the formula racecar when a ‘halo’ driver-protection device is added to the chassis. The halo protection device was introduced at the start of the 2018 racing season as a safety measure against foreign object impacts that a driver may encounter when driving an open-wheel racecar. In the one-year since its introduction, the device has received wide acclaim for protecting the driver on two separate occasions. The benefit of such a safety device certainly cannot be disputed. However, by adding the halo device to a car, it changes the airflow around the vehicle, and most notably, to the engine air-intake and the rear wing. These negative effects in the air supply to the engine, and equally to the downforce created by the rear wing are studied in this paper using numerical technique, and the resulting CFD outputs are presented and discussed. Comparing racecar design prior to and after the introduction of the halo device, it is shown that the design of the air intake and the rear wing has not followed suit since the addition of the halo device. The reduction of engine intake mass flow due to the halo device is computed and presented for various speeds the car may be going. Because of the location of the halo device in relation to the air intake, airflow is directed away from the engine, making the engine perform less than optimal. The reduction is quantified in this paper to show the correspondence to reduce the engine output when compared to a similar car without the halo device. This paper shows that through aerodynamic arguments, the engine in a halo car will not receive unobstructed, clean airflow that a non-halo car does. Another negative effect is on the downforce created by the rear wing. Because the amount of downforce created by the rear wing is influenced by every component that comes before it, when a halo device is added upstream to the rear wing, airflow is obstructed, and less is available for making downforce. This reduction in downforce is especially dramatic as the speed is increased. This paper presents a graph of downforce over a range of speeds for a car with and without the halo device. Acknowledging that although driver safety is paramount, the negative effect of this safety device on the performance of the car should still be well understood so that any possible redesign to mitigate these negative effects can be taken into account in next year’s rules regulation.Keywords: automotive aerodynamics, halo device, downforce. engine intake
Procedia PDF Downloads 1104690 Phytoremediation of Arsenic-Contaminated Soil and Recovery of Valuable Arsenic Products
Authors: Valentine C. Eze, Adam P. Harvey
Abstract:
Contamination of groundwater and soil by heavy metals and metalloids through anthropogenic activities and natural occurrence poses serious environmental challenges globally. A possible solution to this problem is through phytoremediation of the contaminants using hyper-accumulating plants. Conventional phytoremediation treats the contaminated hyper-accumulator biomass as a waste stream which adds no value to the heavy metal(loid)s decontamination process. This study investigates strategies for remediation of soil contaminated with arsenic and the extractive chemical routes for recovery of arsenic and phosphorus from the hyper-accumulator biomass. Pteris cretica ferns species were investigated for their uptake of arsenic from soil containing 200 ± 3ppm of arsenic. The Pteris cretica ferns were shown to be capable of hyper-accumulation of arsenic, with maximum accumulations of about 4427 ± 79mg to 4875 ± 96mg of As per kg of the dry ferns. The arsenic in the Pteris cretica fronds was extracted into various solvents, with extraction efficiencies of 94.3 ± 2.1% for ethanol-water (1:1 v/v), 81.5 ± 3.2% for 1:1(v/v) methanol-water, and 70.8 ± 2.9% for water alone. The recovery efficiency of arsenic from the molybdic acid complex process 90.8 ± 5.3%. Phosphorus was also recovered from the molybdic acid complex process at 95.1 ± 4.6% efficiency. Quantitative precipitation of Mg₃(AsO₄)₂ and Mg₃(PO₄)₂ occurred in the treatment of the aqueous solutions of arsenic and phosphorus after stripping at pH of 8 – 10. The amounts of Mg₃(AsO₄)₂ and Mg₃(PO₄)₂ obtained were 96 ± 7.2% for arsenic and 94 ± 3.4% for phosphorus. The arsenic nanoparticles produced from the Mg₃(AsO₄)₂ recovered from the biomass have the average particles diameter of 45.5 ± 11.3nm. A two-stage reduction process – a first step pre-reduction of As(V) to As(III) with L-cysteine, followed by NaBH₄ reduction of the As(III) to As(0), was required to produced arsenic nanoparticles from the Mg₃(AsO₄)₂. The arsenic nanoparticles obtained are potentially valuable for medical applications, while the Mg₃(AsO₄)₂ could be used as an insecticide. The phosphorus contents of the Pteris cretica biomass was recovered as phosphomolybdic acid complex and converted to Mg₃(PO₄)₂, which could be useful in productions of fertilizer. Recovery of these valuable products from phytoremediation biomass would incentivize and drive commercial industries’ participation in remediation of contaminated lands.Keywords: phytoremediation, Pteris cretica, hyper-accumulator, solvent extraction, molybdic acid process, arsenic nanoparticles
Procedia PDF Downloads 3174689 CRLH and SRR Based Microwave Filter Design Useful for Communication Applications
Authors: Subal Kar, Amitesh Kumar, A. Majumder, S. K. Ghosh, S. Saha, S. S. Sikdar, T. K. Saha
Abstract:
CRLH (composite right/left-handed) based and SRR (split-ring resonator) based filters have been designed at microwave frequency which can provide better performance compared to conventional edge-coupled band-pass filter designed around the same frequency, 2.45 GHz. Both CRLH and SRR are unit cells used in metamaterial design. The primary aim of designing filters with such structures is to realize size reduction and also to realize novel filter performance. The CRLH based filter has been designed in microstrip transmission line, while the SRR based filter is designed with SRR loading in waveguide. The CRLH based filter designed at 2.45 GHz provides an insertion loss of 1.6 dB with harmonic suppression up to 10 GHz with 67 % size reduction when compared with a conventional edge-coupled band-pass filter designed around the same frequency. One dimensional (1-D) SRR matrix loaded in a waveguide shows the possibility of realizing a stop-band with sharp skirts in the pass-band while a stop-band in the pass-band of normal rectangular waveguide with tailoring of the dimensions of SRR unit cells. Such filters are expected to be very useful for communication systems at microwave frequency.Keywords: BPF, CRLH, harmonic, metamaterial, SRR and waveguide
Procedia PDF Downloads 4274688 Investigating the Influence of Roof Fairing on Aerodynamic Drag of a Bluff Body
Authors: Kushal Kumar Chode
Abstract:
Increase in demand for fuel saving and demand for faster vehicles with decent fuel economy, researchers around the world started investigating in various passive flow control devices to improve the fuel efficiency of vehicles. In this paper, A roof fairing was investigated for reducing the aerodynamic drag of a bluff body. The bluff body considered for this work is Ahmed model with a rake angle of 25deg was and subjected to flow with a velocity of 40m/s having Reynolds number of 2.68million was analysed using a commercial Computational Fluid Dynamic (CFD) code Star CCM+. It was evident that pressure drag is the main source of drag on an Ahmed body from the initial study. Adding a roof fairing has delayed the flow separation and resulted in delaying wake formation, thus improving the pressure in near weak and reducing the wake region. Adding a roof fairing of height and length equal to 1/7H and 1/3L respectively has shown a drag reduction by 9%. However, an optimised fairing, which was obtained by changing height, length and width by 5% increase, recorded a drag reduction close 12%.Keywords: Ahmed model, aerodynamic drag, passive flow control, roof fairing, wake formation
Procedia PDF Downloads 4414687 Effectiveness of Control Measures for Ambient Fine Particulate Matters Concentration Improvement in Taiwan
Authors: Jiun-Horng Tsai, Shi-Jie, Nieh
Abstract:
Fine particulate matter (PM₂.₅) has become an important issue all over the world over the last decade. Annual mean PM₂.₅ concentration has been over the ambient air quality standard of PM₂.₅ (annual average concentration as 15μg/m³) which adapted by Taiwan Environmental Protection Administration (TEPA). TEPA, therefore, has developed a number of air pollution control measures to improve the ambient concentration by reducing the emissions of primary fine particulate matter and the precursors of secondary PM₂.₅. This study investigated the potential improvement of ambient PM₂.₅ concentration by the TEPA program and the other scenario for further emission reduction on various sources. Four scenarios had been evaluated in this study, including a basic case and three reduction scenarios (A to C). The ambient PM₂.₅ concentration was evaluated by Community Multi-scale Air Quality modelling system (CMAQ) ver. 4.7.1 along with the Weather Research and Forecasting Model (WRF) ver. 3.4.1. The grid resolutions in the modelling work are 81 km × 81 km for domain 1 (covers East Asia), 27 km × 27 km for domain 2 (covers Southeast China and Taiwan), and 9 km × 9 km for domain 3 (covers Taiwan). The result of PM₂.₅ concentration simulation in different regions of Taiwan shows that the annual average concentration of basic case is 24.9 μg/m³, and are 22.6, 18.8, and 11.3 μg/m³, respectively, for scenarios A to C. The annual average concentration of PM₂.₅ would be reduced by 9-55 % for those control scenarios. The result of scenario C (the emissions of precursors reduce to allowance levels) could improve effectively the airborne PM₂.₅ concentration to attain the air quality standard. According to the results of unit precursor reduction contribution, the allowance emissions of PM₂.₅, SOₓ, and NOₓ are 16.8, 39, and 62 thousand tons per year, respectively. In the Kao-Ping air basin, the priority for reducing precursor emissions is PM₂.₅ > NOₓ > SOₓ, whereas the priority for reducing precursor emissions is PM₂.₅ > SOₓ > NOₓ in others area. The result indicates that the target pollutants that need to be reduced in different air basin are different, and the control measures need to be adapted to local conditions.Keywords: airborne PM₂.₅, community multi-scale air quality modelling system, control measures, weather research and forecasting model
Procedia PDF Downloads 1394686 The Photocatalytic Approach for the Conversion of Polluted Seawater CO₂ into Renewable Source of Energy
Authors: Yasar N. Kavil, Yasser A. Shaban, Radwan K. Al Farawati, Mohamed I. Orif, Shahed U. M. Khanc
Abstract:
Photocatalytic way of reduction of CO₂ in polluted seawater into chemical fuel, methanol, was successfully gained over Cu/C-co-doped TiO₂ nanoparticles under UV and natural sunlight. A homemade stirred batch annular reactor was used to carry out the photocatalytic reduction experiments. Photocatalysts with various Cu loadings (0, 0.5, 1, 3, 5 and 7 wt.%) were synthesized by the sol-gel procedure and were characterized by XRD, SEM, UV–Vis, FTIR, and XPS. The photocatalytic production of methanol was promoted by the co-doping with C and Cu into TiO₂. This improvement was attributed to the modification of bandgap energy and the hindrance of the charges recombination. The polluted seawater showing the yield depended on its background hydrographic parameters. We assessed two types of polluted seawater system, the observed yield was 2910 and 990 µmol g⁻¹ after 5 h of illumination under UV and natural sunlight respectively in system 1 and the corresponding yield in system 2 was 2250 and 910 µmol g⁻¹ after 5 h of illumination. The production of methanol in the case of oxygen-depleted water was low, this is mainly attributed to the competition of methanogenic bacteria over methanol production. The results indicated that the methanol yield produced by Cu-C/TiO₂ was much higher than those of carbon-modified titanium oxide (C/TiO₂) and Degussa (P25-TiO₂). Under the current experimental condition, the optimum loading was achieved by the doping of 3 wt % of Cu. The highest methanol yield was obtained over 1 g L-1 of 3wt% Cu/C-TiO₂.Keywords: CO₂ photoreduction, copper, Cu/C-co-doped TiO₂, methanol, seawater
Procedia PDF Downloads 2784685 Effects of Rice Husk Ash on the Properties of Scrap Tyre Steel Fiber Reinforced High Performance Concrete (RHA-STSFRHAC)
Authors: Isyaka Abdulkadir, Egbe-Ngu Ntui Ogork
Abstract:
This research aims to investigate the effect of Rice Husk Ash (RHA) on Scrap Tyre Steel Fiber Reinforced High Performance Concrete (STSFRHPC). RHA was obtained by control burning of rice husk in a kiln to a temperature of 650-700oC and when cooled sieved through 75µm sieve and characterized. The effect of RHA were investigated on grade 50 STSFRHPC of 1:1.28:1.92 with water cement ratio of 0.39 at additions of Scrap Tyre Steel Fiber (STSF) of 1.5% by volume of concrete and partial replacement of cement with RHA at percentages of 0, 5, 10, 15 and 20. The fresh concrete was tested for slump while the hardened concrete was tested for compressive and splitting tensile strengths respectively at curing ages of 3, 7, 28 and 56 days in accordance with standard procedure. Results of RHA-STSFRHPC indicated a reduction in slump and compressive strength with increase in RHA content, while splitting tensile strength increased with RHA replacement up to 10% and reduction in strength above 10% RHA content. The 28 days compressive strength of RHA-STSFRHPC with up to 10% RHA attained the desired characteristic strength of 50N/mm2 and therefore up to 10% RHA is considered as the optimum replacement dosage in STSFRHPC-RHA.Keywords: compressive strength, high performance concrete, rice husk ash, scrap tyre steel fibers
Procedia PDF Downloads 3374684 Fe₃O₄/SiO₂/TiO₂ Nanoparticles as Catalyst for Recovery of Gold from the Mixture of Au(III) and Cu(II) Ions
Authors: Eko S. Kunarti, Akhmad Syoufian, Indriana Kartini, Agnes
Abstract:
Fe₃O₄/SiO₂/TiO₂ nanoparticles have been synthesized and applied as a photocatalyst for the recovery of gold from the mixture of Au(III) and Cu(II) ions. The synthesis was started by the preparation of magnetite (Fe₃O₄) using coprecipitation and sonication methods, followed by SiO₂ coating on magnetite using sol-gel reactions, and then TiO₂ coating using sol-gel process. Characterization was performed by using infrared spectroscopy, X-ray diffraction, transmission electron microscopy methods. Activity of Fe₃O₄/SiO₂/TiO₂ nanoparticles was evaluated as a photocatalyst for recovery of gold through photoreduction of Au(III) ions in Au(III) and Cu(II) ions mixture with a ratio of 1:1, in a closed reactor equipped with UV lamp. The photoreduction yield was represented as a percentage (%) of reduced Au(III) which was calculated by substraction of initial Au(III) concentration by the unreduced one. The unreduced Au(III) was determined by atomic absorption spectrometry. Results showed that the Fe₃O₄/SiO₂/TiO₂ nanoparticles were successfully synthesised with excellent magnetic and photocatalytic properties. The nanoparticles present optimum activity at a pH of 5 under UV irradiation for 120 minutes. At the optimum condition, the Fe₃O₄/SiO₂/TiO₂ nanoparticles could reduce Au³⁺ to Au⁰ 97.24%. In the mixture of Au(III) and Cu(II) ions, the Au(III) ions are more easily reducible than Cu(II) ions with the reduction results of 96.9% and 45.80% for Au(III) and Cu(II) ions, respectively. In addition, the presence of Cu(II) ions has no significant effect on the amount of gold recovered and its reduction reaction rate.Keywords: Fe₃O₄/SiO₂/TiO₂, photocatalyst, recovery, gold, Au(III) and Cu(II) mixture
Procedia PDF Downloads 2744683 Recycled Plastic Fibers for Minimizing Plastic Shrinkage Cracking of Cement Based Mortar
Authors: B. S. Al-Tulaian, M. J. Al-Shannag, A. M. Al-Hozaimy
Abstract:
The development of new construction materials using recycled plastic is important to both the construction and the plastic recycling industries. Manufacturing of fibers from industrial or post-consumer plastic waste is an attractive approach with such benefits as concrete performance enhancement, and reduced needs for land filling. The main objective of this study is to investigate the effect of plastic fibers obtained locally from recycled waste on plastic shrinkage cracking of ordinary cement based mortar. Parameters investigated include: Fiber length ranging from 20 to 50 mm, and fiber volume fraction ranging from 0% to 1.5% by volume. The test results showed significant improvement in crack arresting mechanism and substantial reduction in the surface area of cracks for the mortar reinforced with recycled plastic fibers compared to plain mortar. Furthermore, test results indicated that there was a slight decrease in compressive strength of mortar reinforced with different lengths and contents of recycled fibers compared to plain mortar. This study suggests that adding more than 1% of RP fibers to mortar, can be used effectively for controlling plastic shrinkage cracking of cement based mortar, and thus results in waste reduction and resources conservation.Keywords: mortar, plastic, shrinkage cracking, compressive strength, RF recycled fibers
Procedia PDF Downloads 4094682 Stress and Social Support as Predictors of Quality of Life: A Case among Flood Victims in Malaysia
Authors: Najib Ahmad Marzuki, Che Su Mustaffa, Johana Johari, Nur Haffiza Rahaman
Abstract:
The purpose of this paper is to examine the effects and relationship of stress and social support towards the quality of life among flood victims in Malaysia. A total of 764 respondents took part in the survey via random sampling. The depression, anxiety, and stress scales were utilized to measure stress while The Multidimensional Scale of Perceived Social Support was used to measure the quality of life. The findings of this study indicate that there were significant correlations between variables in the study. The findings show a significant negative relation between stress and quality of life, and significant positive correlations between support from family as well as support from friends with the quality of life. Stress and support from family were found to be significant predictors and influences the quality of life among flood victims.Keywords: stress, social support, quality of life, flood victims
Procedia PDF Downloads 5574681 The Practice of Low Flow Anesthesia to Reduce Carbon Footprints Sustainability Project
Authors: Ahmed Eid, Amita Gupta
Abstract:
Abstract: Background: Background Medical gases are estimated to contribute to 5% of the carbon footprints produced by hospitals, Desflurane has the largest impact, but all increase significantly when used with N2O admixture. Climate Change Act 2008, we must reduce our carbon emission by 80% of the 1990 baseline by 2050.NHS carbon emissions have reduced by 18.5% (2007-2017). The NHS Long Term Plan has outlined measures to achieve this objective, including a 2% reduction by transforming anaesthetic practices. FGF is an important variable that determines the utilization of inhalational agents and can be tightly controlled by the anaesthetist. Aims and Objectives Environmental safety, Identification of areas of high N20 and different anaesthetic agents used across the St Helier operating theatres and consider improvising on the current practice. Methods: Data was collected from St Helier operating theatres and retrieved daily from Care Station 650 anaesthetic machines. 60 cases were included in the sample. Collected data (average flow rate, amount and type of agent used, duration of surgery, type of surgery, duration, and the total amount of Air, O2 and N2O used. AAGBI impact anaesthesia calculator was used to identify the amount of CO2 produced and also the cost per hour for every pt. Communication via reminder emails to staff emphasized the significance of low-flow anaesthesia and departmental meeting presentations aimed at heightening awareness of LFA, Distribution of AAGBI calculator QR codes in all theatres enables the calculation of volatile anaesthetic consumption and CO2e post each case, facilitating informed environmental impact assessment. Results: A significant reduction in the flow rate use in the 2nd sample was observed, flow rate usage between 0-1L was 60% which means a great reduction of the consumption of volatile anaesthetics and also Co2e. By using LFA we can save money but most importantly we can make our lives much greener and save the planet.Keywords: low flow anesthesia, sustainability project, N₂0, Co2e
Procedia PDF Downloads 684680 Performance of a Lytic Bacteriophage Cocktail against Pseudomonas aeruginosa in Conditions That Simulate the Cystic Fibrosis Lung Environment
Authors: Isaac Martin, Abigail Lark, Sandra Morales, Eric W. Alton, Jane C. Davies
Abstract:
Objectives: The cystic fibrosis (CF) lung is a unique microbiological niche, wherein harmful bacteria persist for many years despite antibiotic therapy. Pseudomonas aeruginosa (Pa), the major culprit leading to lung decline and increased mortality, thrives in the lungs of patients with CF due to several factors that have been linked with poor antibiotic performance. Our group is investigating alternative therapies including bacteriophage cocktails with which we have previously demonstrated efficacy against planktonic organisms. In this study, we explored the effects of a 4-phage cocktail on Pa grown in two different conditions, intended to mirror the CF lung: a) alongside standard antibiotic treatment in pre-formed biofilms (structures formed by Pa-secreted exopolysaccharides which provide both physical and cell division barriers to antimicrobials and host defenses and b) in an acidic environment postulated to be present in the CF airway due both to the primary defect in bicarbonate secretion and secondary effects of inflammation. Methods: 16 Pa strains from CF patients at the Royal Brompton Hospital were selected based on sensitivity to a) ceftazidime/ tobramycin and b) the phage cocktail in a conventional plaque assay. To assess efficacy of phage in biofilms, 96 well plates with Pa (5x10⁷ CFU/ ml) were incubated in static conditions, allowing adherent bacterial colonies to form for 24 hr. Ceftazidime and tobramycin (both at 2 × MIC) were added, +/- bacteriophage (4x10⁸ PFU/mL) for a further 24 hr. Cell viability and biomass were estimated using fluorescent resazurin and crystal violet assays, respectively. To evaluate the effect of pH, strains were grown planktonically in shaking 96 well plates at pH 6.0, 6.6, 7.0 and 7.5 with tobramycin or phage, at varying concentrations. Cell viability was quantified by fluorescent resazurin assay. Results: For the biofilm assay, treatment groups were compared with untreated controls and expressed as percent reduction in cell viability and biomass. Addition of the 4-phage cocktail resulted in a 1.3-fold reduction in cell viability and 1.7-fold reduction in biomass (p < 0.001) when compared to standard antibiotic treatment alone. Notably, there was a 50 ± 15% reduction in cell viability and 60 ± 12% reduction in biomass (95% CI) for the 4 biofilms demonstrating the most resistance to antibiotic treatment. 83% of strains tested (n=6) showed decreased bacterial killing by tobramycin at acidic pHs (p < 0.01). However, 25% of strains (n=12) showed improved phage killing at acidic pHs (p < 0.05), with none showing the pattern of reduced efficacy at acidic pH demonstrated by tobramycin. Conclusion: The 4-phage anti-Pa cocktail tested against Pa performs well in pre-formed biofilms and in acidic environments; two conditions intended to mimic the CF lung. To our knowledge, these are the first data looking at the effects of subtle pH changes on phage-mediated bacterial killing in the context of Pa infection. These findings contribute to a growing body of evidence supporting the use of nebulised lytic bacteriophage as a treatment in the context of lung infection.Keywords: biofilm, cystic fibrosis, pH, Pseudomonas aeruginosa, lytic bacteriophage
Procedia PDF Downloads 1734679 Elaboration and Characterization of Self-Compacting Mortar Based Biopolymer
Authors: I. Djefour, M. Saidi, I. Tlemsani, S. Toubal
Abstract:
Lignin is a molecule derived from wood and also generated as waste from the paper industry. With a view to its valorization and protection of the environment, we are interested in its use as a superplasticizer-type adjuvant in mortars and concretes to improve their mechanical strengths. The additives of the concrete have a very strong influence on the properties of the fresh and / or hardened concrete. This study examines the development and use of industrial waste and lignin extracted from a renewable natural source (wood) in cementitious materials. The use of these resources is known at present as a definite resurgence of interest in the development of building materials. Physicomechanical characteristics of mortars are determined by optimization quantity of the natural superplasticizer. The results show that the mechanical strengths of mortars based on natural adjuvant have improved by 20% (64 MPa) for a W/C ratio = 0.4, and the amount of natural adjuvant of dry extract needed is 40 times smaller than commercial adjuvant. This study has a scientific impact (improving the performance of the mortar with an increase in compactness and reduction of the quantity of water), ecological use of the lignin waste generated by the paper industry) and economic reduction of the cost price necessary to elaboration of self-compacting mortars and concretes).Keywords: biopolymer (lignin), industrial waste, mechanical resistances, self compacting mortars (SCM)
Procedia PDF Downloads 1664678 Surgical Planning for the Removal of Cranial Spheno-orbital Meningioma by Using Personalized Polymeric Prototypes Obtained with Additive Manufacturing Techniques
Authors: Freddy Patricio Moncayo-Matute, Pablo Gerardo Peña-Tapia, Vázquez-Silva Efrén, Paúl Bolívar Torres-Jara, Diana Patricia Moya-Loaiza, Gabriela Abad-Farfán
Abstract:
This study describes a clinical case and the results on the application of additive manufacturing for the surgical planning in the removal of a cranial spheno-orbital meningioma. It is verified that the use of personalized anatomical models and cutting guides helps to manage the cranial anomalies approach. The application of additive manufacturing technology: Fused Deposition Modeling (FDM), as a low-cost alternative, enables the printing of the test anatomical model, which in turn favors the reduction of surgery time, as well the morbidity rate reduction too. And the printing of the personalized cutting guide, which constitutes a valuable aid to the surgeon in terms of improving the intervention precision and reducing the invasive effect during the craniotomy. As part of the results, post-surgical follow-up is included as an instrument to verify the patient's recovery and the validity of the procedure.Keywords: surgical planning, additive manufacturing, rapid prototyping, fused deposition modeling, custom anatomical model
Procedia PDF Downloads 1004677 Psychological Well-Being Among the Freed Kamhalari Girls in Dang
Authors: Jug Maya Chaudhary
Abstract:
The principal objective of this paper has been to assess the level of psychological well-being (PWB) of freed Kamhalari girls sheltered in a governmental rehabilitation center in the Dang district. All the girls (N=100) have been selected for a quantitative study, including 15 cases of in-depth interviews for qualitative study in 2013. The study results suggest that the level of psychological well-being of freed Kamhalaris has not been found to be high; rather they are moderate, with small incidences of a lower level of psychological well-being. Regarding the qualitative study, a total of six themes was identified: physical pain and fatigue then and now, the lasting experience of anxiety, unfair treatment, low self-esteem, depressed mood, and frustration due to current state and confusion. These themes reflected the unrelenting intrusive nature of painful experiences of those affected. This research will provide empathic insight into their past experience. It will add to the body of research on Psychological Well-being of Freed Kamhalari Girls and may generate ideas for intervention research.Keywords: Kamhalari, Experiences, Tharu, Psychological Wellbeing
Procedia PDF Downloads 564676 Psychological Effects of Economic Recession on Educated Youth: Evidences from Pakistan
Authors: Mubashra Khalid, Saadia Amir
Abstract:
This study initiated to explore the empirical relationship between psychological effects of economic recession on the educated youth in Pakistan. The diminishing economic resources during recession can create certain psychological consequences on the physical and cognitive aspects of the individuals. It may generate symptoms like aggression, depression, anxiety, frustration, stress and physical health related problems among the young generation. The sample of the study was consisted of 300 students belonging to six public sector universities of the Punjab province of Pakistan. Two hypotheses were advanced in this study regarding the relationship between recession and its effects on educated youth. The findings of the research represent that a significant relationship exists between decrease in employment opportunities and growing rate of aggression among educated youth and a significant association was found between economic instability and its influence on the learning abilities of the students during recession.Keywords: psychological effects, recession, educated youth
Procedia PDF Downloads 5084675 A Review on Aviation Emissions and Their Role in Climate Change Scenarios
Authors: J. Niemisto, A. Nissinen, S. Soimakallio
Abstract:
Aviation causes carbon dioxide (CO2) emissions and other climate forcers which increase the contribution of aviation on climate change. Aviation industry and number of air travellers are constantly increasing. Aviation industry has an ambitious goal to strongly cut net CO2 emissions. Modern fleet, alternative jet fuels technologies and route optimisation are important technological tools in the emission reduction. Faster approaches are needed as well. Emission trade systems, voluntary carbon offset compensation schemes and taxation are already in operation. Global scenarios of aviation industry and its greenhouse gas emissions and other climate forcers are discussed in this review study based on literature and other published data. The focus is on the aviation in Nordic countries, but also European and global situation are considered. Different emission reduction technologies and compensation modes are examined. In addition, the role of aviation in a single passenger’s (a Finnish consumer) annual carbon footprint is analysed and a comparison of available emission calculators and carbon offset systems is performed. Long-haul fights have a significant role in a single consumer´s and company´s carbon footprint, but remarkable change in global emission level would need a huge change in attitudes towards flying.Keywords: aviation, climate change, emissions, environment
Procedia PDF Downloads 2114674 Multi-Stakeholder Engagement in the Food Waste Ecosystem: Opportunities and Policy Initiatives in Nigeria
Authors: Victor Oyewumi Ogunbiyi
Abstract:
Food waste is a global sustainability issue that demands that multiple stakeholders participate in solving it. This article examines how different food system stakeholders are held responsible in the policy debate related to food waste reduction. The study adopts a qualitative approach, paying attention to the views of both public and private policymakers and constructing their views relating to opportunities and policy initiatives towards waste reduction. The data consists of a list of opportunities and food policy initiatives in the development process in Nigeria. The authors identify three emerging opportunities: sectoral growth, technological demands in food service, and sustainable collaborative behaviour. The findings also revealed key policy initiatives for development: law and regulations, multi-stakeholder collaboration, economic incentives, research, and new knowledge. The study extends the marketing literature on food sustainability by investigating several stakeholders’ roles beyond the practical management of the food services sector. Additionally, considering policy initiative development for food waste mitigation sheds light on how stakeholders’ policy initiatives can sustain the food service sector. Finally, the authors outline policy implications.Keywords: multistakeholder engagement, food services, food waste, policy initiatives, Nigeria
Procedia PDF Downloads 77