Search results for: particle tracking diffusion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3566

Search results for: particle tracking diffusion

1346 Digital Design and Practice of The Problem Based Learning in College of Medicine, Qassim University, Saudi Arabia

Authors: Ahmed Elzainy, Abir El Sadik, Waleed Al Abdulmonem, Ahmad Alamro, Homaidan Al-Homaidan

Abstract:

Problem-based learning (PBL) is an educational modality which stimulates critical and creative thinking. PBL has been practiced in the college of medicine, Qassim University, Saudi Arabia, since the 2002s with offline face to face activities. Therefore, crucial technological changes in paperless work were needed. The aim of the present study was to design and implement the digitalization of the PBL activities and to evaluate its impact on students' and tutors’ performance. This approach promoted the involvement of all stakeholders after their awareness of the techniques of using online tools. IT support, learning resources facilities, and required multimedia were prepared. Students’ and staff perception surveys reflected their satisfaction with these remarkable changes. The students were interested in the new digitalized materials and educational design, which facilitated the conduction of PBL sessions and provided sufficient time for discussion and peer sharing of knowledge. It enhanced the tutors for supervision and tracking students’ activities on the Learning Management System. It could be concluded that introducing of digitalization of the PBL activities promoted the students’ performance, engagement and enabled a better evaluation of PBL materials and getting prompt students as well as staff feedback. These positive findings encouraged the college to implement the digitalization approach in other educational activities, such as Team-Based Learning, as an additional opportunity for further development.

Keywords: multimedia in PBL, online PBL, problem-based learning, PBL digitalization

Procedia PDF Downloads 113
1345 2D Surface Flow Model in The Biebrza Floodplain

Authors: Dorota Miroslaw-Swiatek, Mateusz Grygoruk, Sylwia Szporak

Abstract:

We applied a two-dimensional surface water flow model with irregular wet boundaries. In this model, flow equations are in the form of a 2-D, non-linear diffusion equations which allows to account spatial variations in flow resistance and topography. Calculation domain to simulate the flow pattern in the floodplain is congruent with a Digital Elevation Model (DEM) grid. The rate and direction of sheet flow in wetlands is affected by vegetation type and density, therefore the developed model take into account spatial distribution vegetation resistance to the water flow. The model was tested in a part of the Biebrza Valley, of an outstanding heterogeneity in the elevation and flow resistance distributions due to various ecohydrological conditions and management measures. In our approach we used the highest-possible quality of the DEM in order to obtain hydraulic slopes and vegetation distribution parameters for the modelling. The DEM was created from the cloud of points measured in the LiDAR technology. The LiDAR reflects both the land surface as well as all objects on top of it such as vegetation. Depending on the density of vegetation cover the ability of laser penetration is variable. Therefore to obtain accurate land surface model the “vegetation effect” was corrected using data collected in the field (mostly the vegetation height) and satellite imagery such as Ikonos (to distinguish different vegetation types of the floodplain and represent them spatially). Model simulation was performed for the spring thaw flood in 2009.

Keywords: floodplain flow, Biebrza valley, model simulation, 2D surface flow model

Procedia PDF Downloads 496
1344 Using Geospatial Analysis to Reconstruct the Thunderstorm Climatology for the Washington DC Metropolitan Region

Authors: Mace Bentley, Zhuojun Duan, Tobias Gerken, Dudley Bonsal, Henry Way, Endre Szakal, Mia Pham, Hunter Donaldson, Chelsea Lang, Hayden Abbott, Leah Wilcynzski

Abstract:

Air pollution has the potential to modify the lifespan and intensity of thunderstorms and the properties of lightning. Using data mining and geovisualization, we investigate how background climate and weather conditions shape variability in urban air pollution and how this, in turn, shapes thunderstorms as measured by the intensity, distribution, and frequency of cloud-to-ground lightning. A spatiotemporal analysis was conducted in order to identify thunderstorms using high-resolution lightning detection network data. Over seven million lightning flashes were used to identify more than 196,000 thunderstorms that occurred between 2006 - 2020 in the Washington, DC Metropolitan Region. Each lightning flash in the dataset was grouped into thunderstorm events by means of a temporal and spatial clustering algorithm. Once the thunderstorm event database was constructed, hourly wind direction, wind speed, and atmospheric thermodynamic data were added to the initiation and dissipation times and locations for the 196,000 identified thunderstorms. Hourly aerosol and air quality data for the thunderstorm initiation times and locations were also incorporated into the dataset. Developing thunderstorm climatologies using a lightning tracking algorithm and lightning detection network data was found to be useful for visualizing the spatial and temporal distribution of urban augmented thunderstorms in the region.

Keywords: lightning, urbanization, thunderstorms, climatology

Procedia PDF Downloads 68
1343 Discovering New Organic Materials through Computational Methods

Authors: Lucas Viani, Benedetta Mennucci, Soo Young Park, Johannes Gierschner

Abstract:

Organic semiconductors have attracted the attention of the scientific community in the past decades due to their unique physicochemical properties, allowing new designs and alternative device fabrication methods. Until today, organic electronic devices are largely based on conjugated polymers mainly due to their easy processability. In the recent years, due to moderate ET and CT efficiencies and the ill-defined nature of polymeric systems the focus has been shifting to small conjugated molecules with well-defined chemical structure, easier control of intermolecular packing, and enhanced CT and ET properties. It has led to the synthesis of new small molecules, followed by the growth of their crystalline structure and ultimately by the device preparation. This workflow is commonly followed without a clear knowledge of the ET and CT properties related mainly to the macroscopic systems, which may lead to financial and time losses, since not all materials will deliver the properties and efficiencies demanded by the current standards. In this work, we present a theoretical workflow designed to predict the key properties of ET of these new materials prior synthesis, thus speeding up the discovery of new promising materials. It is based on quantum mechanical, hybrid, and classical methodologies, starting from a single molecule structure, finishing with the prediction of its packing structure, and prediction of properties of interest such as static and averaged excitonic couplings, and exciton diffusion length.

Keywords: organic semiconductor, organic crystals, energy transport, excitonic couplings

Procedia PDF Downloads 252
1342 Tracking of Linarin from the Ethyl Acetate Fraction of Melinjo (Gnetum gnemon L.) Seeds Using Preparative High Performance Liquid Chromatography

Authors: Asep Sukohar, Ramadhan Triyandi, Muhammad Iqbal, Sahidin, Suharyani

Abstract:

Introduction: Resveratrol is a class of bioactive chemicals found in melinjo, which has a wide range of biological actions. The purpose of this study is to determine the linarin content of the melinjo fraksi by using preparative-high-performance liquid chromatography (prep-HPLC). Method: Extraction used the soxhletation method with 96% ethanol solvent. Fractionation used ethyl acetate and ethanol in a ratio of 1:1. Tracing of linarin compound used prep-HPLC with a mobile phase ratio of distilled water: methanol (55: 45, v/v). The presence of linarin was detected using a wavelength of 215 nm. Fourier Transform Infrared (FTIR) was used to identify the functional groups of compound. Result: The retention time required to elute the ethyl acetate fraction was 2.601 minutes. Compound separation identification using Fourier Transform Infrared Spectroscopy - Quest Attenuated Total Reflectance (FTIR - QATR) has a similarity value range with standards from 0 to 1000. The elution results of the ethyl acetate fraction have similar values with the standard compounds linarin (668), resveratrol (578), and catechin (455). Conclusion: Tracing for active compound in the ethyl acetate fraction of Gnetum Gnemon L. using prep-HPLC showed a strong suspicion of the presence of linarin compound.

Keywords: Gnetum gnemon L., linarin, prep-HPLC, fraction ethyl acetate

Procedia PDF Downloads 109
1341 Track and Trace Solution on Land Certificate Production: Indonesian Land Certificate

Authors: Adrian Rifqi, Febe Napitupulu, Erdi Hermawan, Edwin Putra, Yang Leprilian

Abstract:

This article focuses on the implementation of the production improvement process of the Indonesian land certificate product that printed in Perum Peruri as the state-owned enterprises. Based on the data obtained, there are several complaints from customers of the 2019 land certificate production. The complaints become a negative value to loyal customers of Perum Peruri. Almost all the complaints are referring to ‘defective printouts and the difference between products in packaging and packaging labels both in terms of type and quantity’. To overcome this problem, we intend to make an improvement to the production process that focuses on complaints ‘there is a difference between products in packaging with packaging labels’. Improvements in the land certificate production process are relying on the technology of the scales and QR code on the packaging label. In addition, using the QR code on the packaging label will facilitate the process of tracking product data. With this method, we hope to reduce the error rate between products in packaging with the packaging label both in terms of quantity, type, and product number on the land certificate and error rate of sending land certificates, which will be sent to many places to 0%. With this solution, we also hope to get precise data and real-time reports on the production of land certificates in the near future, so track and trace implementation can be done as the solution of the land certificate production.

Keywords: land certificates, QR code, track and trace, packaging

Procedia PDF Downloads 155
1340 Adsorption of Basic Dyes Using Activated Carbon Prepared from Date Palm Fibre

Authors: Riham Hazzaa , Mohamed Hussien Abd El Megid

Abstract:

Dyes are toxic and cause severe problems to aquatic environment. The use of agricultural solid wastes is considered as low-cost and eco-friendly adsorbents for removing dyes from waste water. Date palm fibre, an abundant agricultural by-product in Egypt was used to prepare activated carbon by physical activation method. This study investigates the use of date palm fiber (DPF) and activated carbon (DPFAC) for the removal of a basic dye, methylene blue (MB) from simulated waste water. The effects of temperature, pH of solution, initial dye (concentration, adsorbent dosage and contact time were studied. The experimental equilibrium adsorption data were analyzed by Langmuir, Freundlich, Temkin, Dubinin, Radushkevich and Harkins–Jura isotherms. Adsorption kinetics data were modeled using the pseudo-first and pseudo-second order and Elvoich equations. The mechanism of the adsorption process was determined from the intraparticle diffusion model. The results revealed that as the initial dye concentration , amount of adsorbent and temperature increased, the percentage of dye removal increased. The optimum pH required for maximum removal was found to be 6. The adsorption of methylene blue dye was better described by the pseudo-second-order equation. Results indicated that DPFAC and DPF could be an alternative for more costly adsorbents used for dye removal.

Keywords: adsorption, basic dye, palm fiber, activated carbon

Procedia PDF Downloads 329
1339 Photo-Electrochemical/Electro-Fenton Coupling Oxidation System with Fe/Co-Based Anode and Cathode Metal-Organic Frameworks Derivative Materials for Sulfamethoxazole Treatment

Authors: Xin Chen, Xinyong Li, Qidong Zhao, Dong Wang

Abstract:

A new coupling system was constructed by combining photo-electrochemical cell with electro-fenton cell (PEC-EF). The electrode material in this system was derived from MnyFe₁₋yCo Prussian-Blue-Analog (PBA). Mn₀.₄Fe₀.₆Co₀.₆₇-N@C spin-coated on carbon paper behaved as the gas diffusion cathode and Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ spin-coated on fluorine-tin oxide glass (FTO) as anode. The two separated cells could degrade Sulfamethoxazole (SMX) simultaneously and some coupling mechanisms by PEC and EF enhancing the degradation efficiency were investigated. The continuous on-site generation of H₂O₂ at cathode through an oxygen reduction reaction (ORR) was realized over rotating ring-disk electrode (RRDE). The electron transfer number (n) of the ORR with Mn₀.₄Fe₀.₆Co₀.₆₇-N@C was 2.5 in the selected potential and pH range. The photo-electrochemical properties of Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ were systematically studied, which displayed good response towards visible light. The photoinduced electrons at anode can transfer to cathode for further use. Efficient photo-electro-catalytic performance was observed in degrading SMX. Almost 100% SMX removal was achieved in 120 min. This work not only provided a highly effective technique for antibiotic treatment but also revealed the synergic effect between PEC and EF.

Keywords: electro-fenton, photo-electrochemical, synergic effect, sulfamethoxazole

Procedia PDF Downloads 178
1338 Sediment Patterns from Fluid-Bed Interactions: A Direct Numerical Simulations Study on Fluvial Turbulent Flows

Authors: Nadim Zgheib, Sivaramakrishnan Balachandar

Abstract:

We present results on the initial formation of ripples from an initially flattened erodible bed. We use direct numerical simulations (DNS) of turbulent open channel flow over a fixed sinusoidal bed coupled with hydrodynamic stability analysis. We use the direct forcing immersed boundary method to account for the presence of the sediment bed. The resolved flow provides the bed shear stress and consequently the sediment transport rate, which is needed in the stability analysis of the Exner equation. The approach is different from traditional linear stability analysis in the sense that the phase lag between the bed topology, and the sediment flux is obtained from the DNS. We ran 11 simulations at a fixed shear Reynolds number of 180, but for different sediment bed wavelengths. The analysis allows us to sweep a large range of physical and modelling parameters to predict their effects on linear growth. The Froude number appears to be the critical controlling parameter in the early linear development of ripples, in contrast with the dominant role of particle Reynolds number during the equilibrium stage.

Keywords: direct numerical simulation, immersed boundary method, sediment-bed interactions, turbulent multiphase flow, linear stability analysis

Procedia PDF Downloads 181
1337 Improving Physicochemical Properties of Milk Powder and Lactose-Free Milk Powder with the Prebiotic Carrier

Authors: Chanunya Fahwan, Supat Chaiyakul

Abstract:

A lactose-free diet is imperative for those with lactose intolerance and experiencing milk intolerance. This entails eliminating milk-based products, which may result in dietary and nutritional challenges and the main problems of Lactose hydrolyzed milk powder during production were the adhesion in the drying chamber and low-yield and low-quality powder. The use of lactose-free milk to produce lactose-free milk powder was studied here. Development of two milk powder formulas from cow's milk and lactose-free cow's milk by using a substitute for maltodextrin, Polydextrose (PDX), Resistant Starch (RS), Cellobiose (CB), and Resistant Maltodextrin (RMD) to improve quality and reduce the glycemic index from maltodextrin, which are carriers that were used in industry at three experimental levels 10%, 15% and 20% the properties of milk powder were studied such as color, moisture content, percentage yield (%yield) and solubility index. The experiment revealed that prebiotic carriers could replace maltodextrin and improve quality, such as solubility and percentage yield, and enriched nutrients, such as dietary fiber. CB, RMD, and PDX are three possible carriers, which are applied to both regular cow's milk formula and lactose-free cow milk.

Keywords: lactose-free milk powder, prebiotic carrier, co-particle, glycemic index

Procedia PDF Downloads 77
1336 Microwave Assisted Synthesis of Ag/ZnO Sub-Microparticles Deposited on Various Cellulose Surfaces

Authors: Lukas Munster, Pavel Bazant, Ivo Kuritka

Abstract:

Zinc oxide sub-micro particles and metallic silver nano particles (Ag/ZnO) were deposited on micro crystalline cellulose surface by a fast, simple and environmentally friendly one-pot microwave assisted solvo thermal synthesis in an open vessel system equipped with an external reflux cooler. In order to increase the interaction between the surface of cellulose and the precipitated Ag/ZnO particles, oxidized form of cellulose (cellulose dialdehyde, DAC) prepared by periodate oxidation of micro crystalline cellulose was added to the reaction mixture of Ag/ZnO particle precursors and untreated micro crystalline cellulose. The structure and morphology of prepared hybrid powder materials were analysed by X-ray diffraction (XRD), energy dispersive analysis (EDX), scanning electron microscopy (SEM) and nitrogen absorption method (BET). Microscopic analysis of the prepared materials treated by ultra-sonication showed that Ag/ZnO particles deposited on the cellulose/DAC sample exhibit increased adhesion to the surface of the cellulose substrate which can be explained by the DAC adhesive effect in comparison with the material prepared without DAC addition.

Keywords: microcrystalline cellulose, microwave synthesis, silver nanoparticles, zinc oxide sub-microparticles, cellulose dialdehyde

Procedia PDF Downloads 473
1335 Thermochemical Conversion: Jatropha Curcus in Fixed Bed Reactor Using Slow Pyrolysis

Authors: Vipan Kumar Sohpal, Rajesh Kumar Sharma

Abstract:

Thermo-chemical conversion of non-edible biomass offers an efficient and economically process to provide valuable fuels and prepare chemicals derived from biomass in the context of developing countries. Pyrolysis has advantages over other thermochemical conversion techniques because it can convert biomass directly into solid, liquid and gaseous products by thermal decomposition of biomass in the absence of oxygen. The present paper aims to focus on the slow thermochemical conversion processes for non-edible Jatropha curcus seed cake. The present discussion focuses on the effect of nitrogen gas flow rate on products composition (wt %). In addition, comparative analysis has been performed for different mesh size for product composition. Result shows that, slow pyrolysis experiments of Jatropha curcus seed cake in fixed bed reactor yield the bio-oil 18.42 wt % at a pyrolysis temperature of 500°C, particle size of -6+8 mesh number and nitrogen gas flow rate of 150 ml/min.

Keywords: Jatropha curcus, thermo-chemical, pyrolysis, product composition, yield

Procedia PDF Downloads 427
1334 Assessing Antimicrobial Activity of Various Plant Extracts on Midgutmicroflora of Aedesaegypti

Authors: V. Baweja, K. K. Gupta, V. Dubey, C. Keshavam

Abstract:

Antimicrobial activity of six indigenous plants such as Tulsi Ocimum sanctum, Neem Azadirachta indica, Aloe vera, Turmeric Curcuma longa, Lantana Lantana camara, and Clove Syzygium aromaticum was assessed against the gut microbiota of the dengue fever mosquito Aedes aegypti, keeping in view that the presence of midgut bacteria may affect the ability of the vector to transmit pathogens. Eleven different types of bacterial clones were isolated from the midgut of lab-reared fourth instar larvae of Aedes aegypti and were grown on LB agar medium at an optimum temperature of 25 ºC. Identification of these bacteria was done on the basis of their colony characteristic such as colony size, shape, opacity, elevation, consistency, and growth. Light microscopic studies of the gut microbiota revealed dominance of Gram-negative cocci over gram positive cocci and bacilli and Gram-negative bacilli. Identification of species was done by chemical characterization of the colonies. Crude extracts of all test plants were screened for their antimicrobial activities against gut microbiota by disc diffusion assay. The zone of exclusion seen after 24 hr of incubation in different assays revealed the most potent antibacterial activities in neem followed by clove and turmeric. Lantana and Aloe vera were least effective.

Keywords: plant extract, aedes, dengue, antimicrobial activity

Procedia PDF Downloads 399
1333 Competitive Adsorption of Heavy Metals onto Natural and Activated Clay: Equilibrium, Kinetics and Modeling

Authors: L. Khalfa, M. Bagane, M. L. Cervera, S. Najjar

Abstract:

The aim of this work is to present a low cost adsorbent for removing toxic heavy metals from aqueous solutions. Therefore, we are interested to investigate the efficiency of natural clay minerals collected from south Tunisia and their modified form using sulfuric acid in the removal of toxic metal ions: Zn(II) and Pb(II) from synthetic waste water solutions. The obtained results indicate that metal uptake is pH-dependent and maximum removal was detected to occur at pH 6. Adsorption equilibrium is very rapid and it was achieved after 90 min for both metal ions studied. The kinetics results show that the pseudo-second-order model describes the adsorption and the intraparticle diffusion models are the limiting step. The treatment of natural clay with sulfuric acid creates more active sites and increases the surface area, so it showed an increase of the adsorbed quantities of lead and zinc in single and binary systems. The competitive adsorption study showed that the uptake of lead was inhibited in the presence of 10 mg/L of zinc. An antagonistic binary adsorption mechanism was observed. These results revealed that clay is an effective natural material for removing lead and zinc in single and binary systems from aqueous solution.

Keywords: heavy metal, activated clay, kinetic study, competitive adsorption, modeling

Procedia PDF Downloads 219
1332 A Constrained Model Predictive Control Scheme for Simultaneous Control of Temperature and Hygrometry in Greenhouses

Authors: Ayoub Moufid, Najib Bennis, Soumia El Hani

Abstract:

The objective of greenhouse climate control is to improve the culture development and to minimize the production costs. A greenhouse is an open system to external environment and the challenge is to regulate the internal climate despite the strong meteorological disturbances. The internal state of greenhouse considered in this work is defined by too relevant and coupled variables, namely inside temperature and hygrometry. These two variables are chosen to describe the internal state of greenhouses due to their importance in the development of plants and their sensitivity to external climatic conditions, sources of weather disturbances. A multivariable model is proposed and validated by considering a greenhouse as black-box system and the least square method is applied to parameters identification basing on collected experimental measures. To regulate the internal climate, we propose a Model Predictive Control (MPC) scheme. This one considers the measured meteorological disturbances and the physical and operational constraints on the control and state variables. A successful feasibility study of the proposed controller is presented, and simulation results show good performances despite the high interaction between internal and external variables and the strong external meteorological disturbances. The inside temperature and hygrometry are tracking nearly the desired trajectories. A comparison study with an On/Off control applied to the same greenhouse confirms the efficiency of the MPC approach to inside climate control.

Keywords: climate control, constraints, identification, greenhouse, model predictive control, optimization

Procedia PDF Downloads 201
1331 Helicopter Exhaust Gases Cooler in Terms of Computational Fluid Dynamics (CFD) Analysis

Authors: Mateusz Paszko, Ksenia Siadkowska

Abstract:

Due to the low-altitude and relatively low-speed flight, helicopters are easy targets for actual combat assets e.g. infrared-guided missiles. Current techniques aim to increase the combat effectiveness of the military helicopters. Protection of the helicopter in flight from early detection, tracking and finally destruction can be realized in many ways. One of them is cooling hot exhaust gasses, emitting from the engines to the atmosphere in special heat exchangers. Nowadays, this process is realized in ejective coolers, where strong heat and momentum exchange between hot exhaust gases and cold air ejected from atmosphere takes place. Flow effects of air, exhaust gases; mixture of those two and the heat transfer between cold air and hot exhaust gases are given by differential equations of: Mass transportation–flow continuity, ejection of cold air through expanding exhaust gasses, conservation of momentum, energy and physical relationship equations. Calculation of those processes in ejective cooler by means of classic mathematical analysis is extremely hard or even impossible. Because of this, it is necessary to apply the numeric approach with modern, numeric computer programs. The paper discussed the general usability of the Computational Fluid Dynamics (CFD) in a process of projecting the ejective exhaust gases cooler cooperating with helicopter turbine engine. In this work, the CFD calculations have been performed for ejective-based cooler cooperating with the PA W3 helicopter’s engines.

Keywords: aviation, CFD analysis, ejective-cooler, helicopter techniques

Procedia PDF Downloads 326
1330 Ultrafine Non Water Soluble Drug Particles

Authors: Shahnaz Mansouri, David Martin, Xiao Dong Chen, Meng Wai Woo

Abstract:

Ultrafine hydrophobic and non-water-soluble drugs can increase the percentage of absorbed compared to their initial dosage. This paper provides a scalable new method of making ultrafine particles of substantially insoluble water compounds specifically, submicron particles of ethanol soluble and water insoluble pharmaceutical materials by steaming an ethanol droplet to prepare a suspension and then followed by immediate drying. This suspension is formed by adding evaporated water molecules as an anti-solvent to the solute of the samples and in early stage of precipitation continued to dry by evaporating both solvent and anti-solvent. This fine particle formation has produced fast dispersion powder in water. The new method is an extension of the antisolvent vapour precipitation technique which exposes a droplet to an antisolvent vapour with reference to the dissolved materials within the droplet. Ultrafine vitamin D3 and ibuprofen particles in the submicron ranges were produced. This work will form the basis for using spray dryers as high-throughput scalable micro-precipitators.

Keywords: single droplet drying, nano size particles, non-water-soluble drugs, precipitators

Procedia PDF Downloads 480
1329 Cooling of Exhaust Gases Emitted Into the Atmosphere as the Possibility to Reduce the Helicopter Radiation Emission Level

Authors: Mateusz Paszko, Mirosław Wendeker, Adam Majczak

Abstract:

Every material body that temperature is higher than 0K (absolute zero) emits infrared radiation to the surroundings. Infrared radiation is highly meaningful in military aviation, especially in military applications of helicopters. Helicopters, in comparison to other aircraft, have much lower flight speeds and maneuverability, which makes them easy targets for actual combat assets like infrared-guided missiles. When designing new helicopter types, especially for combat applications, it is essential to pay enormous attention to infrared emissions of the solid parts composing the helicopter’s structure, as well as to exhaust gases egressing from the engine’s exhaust system. Due to their high temperature, exhaust gases, egressed to the surroundings are a major factor in infrared radiation emission and, in consequence, detectability of a helicopter performing air combat operations. Protection of the helicopter in flight from early detection, tracking and finally destruction can be realized in many ways. This paper presents the analysis of possibilities to decrease the infrared radiation level that is emitted to the environment by helicopter in flight, by cooling exhaust in special ejection-based coolers. The paper also presents the concept 3D model and results of numeric analysis of ejective-based cooler cooperation with PA-10W turbine engine. Numeric analysis presented promising results in decreasing the infrared emission level by PA W-3 helicopter in flight.

Keywords: exhaust cooler, helicopter propulsion, infrared radiation, stealth

Procedia PDF Downloads 343
1328 Senior Leadership Team Coaching in Action: Creating High-Performance Teams

Authors: Siqi Fang, Jingxi Hou

Abstract:

Positive psychology and coaching psychology share a number of fundamental assumptions and common themes. Blending positive psychology, mindfulness, and coaching psychology, our work in team coaching with leaders enhances both leadership and team effectiveness. Although individual coaching has proven to be effective, this article advocates the benefits of leadership coaching in team settings, because durable changes in leadership behaviors are more likely to occur. Does leadership team coaching really work? Does it help improve senior leadership team effectiveness and productivity? This action research study answers these questions by tracking the progress of three typical senior leadership teams consisting of 31 executives participating in a six-month team coaching program. Assessments (pre- and post), workshops, and feedback based on ego development theories and mindfulness were applied to upgrade the senior leadership teams’ transformational stages and reframe their organizational leadership cultures. Results suggest that the team effectiveness of the three leadership teams increased up to 43 percent according to post-survey feedback from superior, direct report, and peers. Discussion is offered to show that senior leadership team coaching help teams to achieve a consensus on common purposes, establish a foundation of trust, improve collective skills, and promote efficient operation. All factors translate into better team performance. Implications of the results for future executive development programs are discussed and specific recommendations are provided.

Keywords: action research, ego development, mindfulness, senior leadership team coaching, team effectiveness, transformational stages

Procedia PDF Downloads 364
1327 Fabrication of Modified Chitosan-Gold Nanoshell with Mercaptopropionic Acid(MPA) for γ-Aminobutyric Acid Detection as a Surface-Enhanced Raman Scattering Substrate

Authors: Bi Wa, Su-Yeon Kwon, Ik-Joong Kang

Abstract:

Surface-enhanced Raman Scattering (SERS) as the principle for enhancing Raman scattering by molecules adsorbed on rough metal surfaces or by nanostructures is used to detect the concentration change of γ-Aminobutyric Acid (GABA). GABA is the mainly inhibitory neurotransmitter in the mammalian central nervous system in the human body. It plays such significant role in reducing neuronal excitability throughout the nervous system. In this case, the Mercaptopropionic Acid (MPA) is used to modified chitosan –gold nanoshell, which enhances the absorption between GABA and Chitosan-gold nanoshell. The sulfur end of the MPA is linked to gold which is the surface of the chitosan nanoparticles via the very strong S–Au bond, while a functional group (carboxyl group) attached to GABA. The controlling of particles’ size and the surface morphology are also the important factors during the whole experiment. The particle around 100nm is using to link to MPA, and the range of GABA from 1mM to 30mM was detected by the Raman Scattering to obtain the calibrate curve. In this study, DLS, SEM, FT-IR, UV, SERS were used to analyze the products to obtain the conclusion.

Keywords: chitosan-gold nanoshell, mercaptopropionic acid, γ-aminobutyric acid, surface-enhanced raman scattering

Procedia PDF Downloads 240
1326 Developing a Driving Simulator with a Navigation System to Measure Driver Distraction, Workload, Driving Safety and Performance

Authors: Tamer E. Yared

Abstract:

The use of driving simulators has made laboratory testing easier. It has been proven to be valid for testing driving ability by many researchers. One benefit of using driving simulators is keeping the human subjects away from traffic hazards, which drivers usually face in a real driving environment while performing a driving experiment. In this study, a driving simulator was developed with a navigation system using a game development software (Unity 3D) and C-sharp codes to measure and evaluate driving performance, safety, and workload for different driving tasks. The driving simulator hardware included a gaming steering wheel and pedals as well as a monitor to view the driving tasks. Moreover, driver distraction was evaluated by utilizing an eye-tracking system working in conjunction with the driving simulator. Twenty subjects were recruited to evaluate driver distraction, workload, driving safety, and performance, as well as provide their feedback about the driving simulator. The subjects’ feedback was obtained by filling a survey after conducting several driving tasks. The main question of that survey was asking the subjects to compare driving on the driving simulator with real driving. Furthermore, other aspects of the driving simulator were evaluated by the subjects in the survey. The survey revealed that the recruited subjects gave an average score of 7.5 out of 10 to the driving simulator when compared to real driving, where the scores ranged between 6 and 8.5. This study is a preliminary effort that opens the door for more improvements to the driving simulator in terms of hardware and software development, which will contribute significantly to driving ability testing.

Keywords: driver distraction, driving performance, driving safety, driving simulator, driving workload, navigation system

Procedia PDF Downloads 165
1325 Modern Sports and Imperial Solidarity: Sports, Mutiny and British Army in Colonial Malabar (1900-1930)

Authors: Anas Ali

Abstract:

The British administration at Malabar, the southern coastal commercial outpost in the Indian Subcontinent, faced with a series of perpetual revolts from the Mappila Muslim peasants during the last decades of the 19th and early decades of the 20th century. The control of Malabar region was a concern for the British administrators as the region was a prime centre of spice trade and plantation products. The Madras government set up a special police battalion called the Malabar Special Police in 1884 and summoned different army battalions to Malabar to crush the revolts. The setting up of army camps in the rural Malabar led to the diffusion of modern sports as the army men played different games in the garrisons and with the local people. For the imperial army men deployed in Malabar, sports acted as a viable medium to strengthen solidarity with other European settlers. They actively participated in the ‘Canterbury Week’, an annual sporting event organized by the European planters and organized tournaments among themselves. This paper would argue that, sports enabled the imperial army men, European planters and British administrators to build camaraderie that enabled them to manifest their imperial solidarity during the time of these constant revolts. Based on newspaper reports and colonial memoirs, this paper would look at how modern sports enabled the imperial army men to be ‘good in health’ and create a feeling of ‘being at home’ during this period.

Keywords: imperial army, Malabar, modern sports, mutiny

Procedia PDF Downloads 208
1324 Effect of Heat Treatment on Columnar Grain Growth and Goss Texture on Surface in Grain-Oriented Electrical Steels

Authors: Jungkyun Na, Jaesang Lee, Yang Mo Koo

Abstract:

In this study to find a replacement for expensive secondary recrystallization in GO electrical steel production, effect of heat treatment on the formation of columnar grain and Goss texture is investigated. The composition of the sample is Fe-2.0Si-0.2C. This process involves repeating of cold rolling and decarburization as a replacement for secondary recrystallization. By cold-rolling shear band is made and Goss grain grows from shear band by decarburization. By doing another cold rolling, some Goss texture is newly formed from the shear band, and some Goss texture is retained in microbands. To determine whether additional heat treatment with H2 atmosphere is needed on decarburization process for growth of Goss texture, comparing between decarburization and heat treatment with H2 atmosphere is performed. Also, to find optimum condition for heat treatment, heat treatment with various time and temperature is performed. It was found that increase in the number of cold rolling and heat treatment increases Goss texture. Both high Goss texture and good columnar structure is achieved at 900℃, and this temperature is within a+r phase region. Heat treatment at a temperature higher than a+r phase region caused carbon diffusion and this made layer with Goss grain decrease.

Keywords: electrical steel, Goss texture, columnar structure, normal grain growth

Procedia PDF Downloads 214
1323 Geotechnical Characterization of Landslide in Dounia Park, Algiers, Algeria

Authors: Mira Filali, Amar Nechnech

Abstract:

Most landslides in Algiers take place in Piacenzian marls of the Sahel (port in Arabic) and cause severe damage to properties and infrastructures. The aim of this paper is to describe the results of experimental as well as theoretical analysis of landslides. In order to understand the process which caused this slope instabilities, the results of geotechnical investigation carried out by the laboratory of construction (LNHC) laboratory in the area of Dounia park were analyzed, including particle size distribution, Atterberg limits, shear strength, odometer and pressuremeter tests. The study shows that the soils exhibited a high capacity to swelling according to index plasticity and clay content. Highs limit liquidity (LL) (53.45%) means that the soils are susceptible to landslides. The stability analysis carried out using finite element method, shows that the slope is stable (Fs > 1) in dry condition and in static state. Despite this results, the stable site could be described as only conditionally stable because slope failure can occur under combined effect of different factors. In fact the safety factor obtained by applying load when the phreatic surface is at ground, less than 1.5.

Keywords: index properties, landslides, safety factor, slope stability

Procedia PDF Downloads 232
1322 Investigation into the Homoepitaxy of AlGaN/GaN Heterostructure via Molecular Beam Epitaxy

Authors: Jiajia Yao, Guanlin Wu, Fang Liu, Junshuai Xue, Yue Hao

Abstract:

As the production process of self-standing GaN substrates evolves, the commercialization of low dislocation density, large-scale, semi-insulating self-standing GaN substrates is gradually becoming a reality. This advancement has given rise to increased interest in GaN materials' homoepitaxial technology. However, at the homoepitaxial interface, there are considerable concentrations of impurity elements, including C, Si, and O, which generate parasitic leakage channels at the re-growth junction. This phenomenon results in leaked HEMTs that prove difficult to switch off, rendering them effectively non-functional. The emergence of leakage channels can also degrade the high-frequency properties and lower the power devices' breakdown voltage. In this study, the uniform epitaxy of AlGaN/GaN heterojunction with high electron mobility was accomplished through the surface treatment of the GaN substrates prior to growth and the design of the AlN isolation layer structure. By employing a procedure combining gallium atom in-situ cleaning and plasma nitridation, the C and O impurity concentrations at the homoepitaxial interface were diminished to the scale of 10¹⁷ cm-³. Additionally, the 1.5 nm nitrogen-rich AlN isolation layer successfully prevented the diffusion of Si impurities into the GaN channel layer. The result was an AlGaN/GaN heterojunction with an electron mobility of 1552 cm²/Vs and an electron density of 1.1 × 10¹³ cm-² at room temperature, obtained on a Fe-doped semi-insulating GaN substrate.

Keywords: MBE, AlGaN/GaN, homogenerous epitaxy, HEMT

Procedia PDF Downloads 63
1321 A QoE-driven Cross-layer Resource Allocation Scheme for High Traffic Service over Open Wireless Network Downlink

Authors: Liya Shan, Qing Liao, Qinyue Hu, Shantao Jiang, Tao Wang

Abstract:

In this paper, a Quality of Experience (QoE)-driven cross-layer resource allocation scheme for high traffic service over Open Wireless Network (OWN) downlink is proposed, and the related problem about the users in the whole cell including the users in overlap region of different cells has been solved.A method, in which assess models of the BestEffort service and the no-reference assess algorithm for video service are adopted, to calculate the Mean Opinion Score (MOS) value for high traffic service has been introduced. The cross-layer architecture considers the parameters in application layer, media access control layer and physical layer jointly. Based on this architecture and the MOS value, the Binary Constrained Particle Swarm Optimization (B_CPSO) algorithm is used to solve the cross-layer resource allocation problem. In addition,simulationresults show that the proposed scheme significantly outperforms other schemes in terms of maximizing average users’ MOS value for the whole system as well as maintaining fairness among users.

Keywords: high traffic service, cross-layer resource allocation, QoE, B_CPSO, OWN

Procedia PDF Downloads 537
1320 Examining the Perceptions of Religious Stakeholders Towards Religious Tourism Development

Authors: Sotiroula Liasidou, Katerina Pericleous, Zanete Garanti,

Abstract:

Traveling for religious and pilgrimage purposes consists of an early-stage motivation for the historical development of tourism. Sacred places have become important attractions for local and foreign visitors, and many countries invest in the development of religious and pilgrimage tourism. Cyprus has a rich tradition as an important place for the establishment and diffusion of the Christian Orthodox Religion (Greek). Being considered the ‘island of Saints’, Cyprus sets strong foundations to be recognised as a spiritual destination of devotion for visitors interested in discovering the roots and the spiritual essence of the Christian Orthodox Religion. The paper elucidates on bringing together the fact of whether tourism in sacred places affects spirituality and religiosity. Thus, the aim is to consider the perceptions of the main religious stakeholders, including monastery abbots, in relation to the development of religious tourism. The aim of the study is fulfilled by incorporating questionnaires targeting the responses of the involved religious key players and stakeholders. The results of the study are indicative and provide an understanding in terms of religious tourism as an important product by interpreting the stance of religious stakeholders. In general, religious leaders support tourism in religious sites and argue that spirituality and holiness can be maintained as long there is a policy that is followed both by religious and tourism policymakers. Undoubtedly, establishing Cyprus as a religious tourism destination would bring many economic and social benefits.

Keywords: religious tourism, pilgrimage, Cyprus, Christian Orthodox Religion, sacred places, monasteries

Procedia PDF Downloads 138
1319 Spatial Object-Oriented Template Matching Algorithm Using Normalized Cross-Correlation Criterion for Tracking Aerial Image Scene

Authors: Jigg Pelayo, Ricardo Villar

Abstract:

Leaning on the development of aerial laser scanning in the Philippine geospatial industry, researches about remote sensing and machine vision technology became a trend. Object detection via template matching is one of its application which characterized to be fast and in real time. The paper purposely attempts to provide application for robust pattern matching algorithm based on the normalized cross correlation (NCC) criterion function subjected in Object-based image analysis (OBIA) utilizing high-resolution aerial imagery and low density LiDAR data. The height information from laser scanning provides effective partitioning order, thus improving the hierarchal class feature pattern which allows to skip unnecessary calculation. Since detection is executed in the object-oriented platform, mathematical morphology and multi-level filter algorithms were established to effectively avoid the influence of noise, small distortion and fluctuating image saturation that affect the rate of recognition of features. Furthermore, the scheme is evaluated to recognized the performance in different situations and inspect the computational complexities of the algorithms. Its effectiveness is demonstrated in areas of Misamis Oriental province, achieving an overall accuracy of 91% above. Also, the garnered results portray the potential and efficiency of the implemented algorithm under different lighting conditions.

Keywords: algorithm, LiDAR, object recognition, OBIA

Procedia PDF Downloads 242
1318 Application of Relative Regional Total Energy in Rotary Drums with Axial Segregation Characteristics

Authors: Qiuhua Miao, Peng Huang, Yifei Ding

Abstract:

Particles with different properties tend to be unevenly distributed along an axial direction of the rotating drum, which is usually ignored. Therefore, it is important to study the relationship between axial segregation characteristics and particle crushing efficiency in longer drums. In this paper, a relative area total energy (RRTE) index is proposed, which aims to evaluate the overall crushing energy distribution characteristics. Based on numerical simulation verification, the proposed RRTE index can reflect the overall grinding effect more comprehensively, clearly representing crushing energy distribution in different drum areas. Furthermore, the proposed method is applied to the relation between axial segregation and crushing energy in drums. Compared with the radial section, the collision loss energy of the axial section can better reflect the overall crushing effect in long drums. The axial segregation characteristics directly affect the total energy distribution between medium and abrasive, reducing overall crushing efficiency. Therefore, the axial segregation characteristics should be avoided as much as possible in the crushing of the long rotary drum.

Keywords: relative regional total energy, crushing energy, axial segregation characteristics, rotary drum

Procedia PDF Downloads 84
1317 Biosurfactant-Mediated Nanoparticle Synthesis by Bacillus subtilis

Authors: Satya Eswari Jujjavarapu, Swasti Dhagat, Lata Upadhyay, Reecha Sahu

Abstract:

Silver nanoparticles have a broad range of antimicrobial and antifungal properties ranging from soaps, pastes to sterilization and drug delivery systems. These can be synthesized by physical, chemical and biological methods; biological methods being the most popular owing to their non-toxic nature and reduced energy requirements. Microbial surfactants, produced on the microbial cell surface or excreted extracellularly are an alternative to synthetic surfactants for the production of silver nanoparticles. Hence, they are also called as green molecules. Microbial lipopeptide surfactants (biosurfactant) exhibit anti-tumor and anti-microbial properties and can be used as drug delivery agents. In this study, biosurfactant was synthesized by using a strain of acillus subtilis. The biosurfactant thus produced was analysed by emulsification assay, oil spilling test, and haemolytic test. Biosurfactant-mediated silver nanoparticles were synthesised by microwave irradiation of the culture supernatant and further characterized by UV–vis spectroscopy for a range of 400-600 nm. The UV–vis spectra showed a surface plasmon resonance vibration band at 410 nm corresponding to the peak of silver nanoparticles.

Keywords: biosurfactant, Bacillus subtilis, silver nano particle, lipopeptide

Procedia PDF Downloads 234