Search results for: dynamics of polymeric liquid
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5018

Search results for: dynamics of polymeric liquid

1868 Towards a Biologically Inspired Supercritical Airfoil Adapted for Gliding Cross-Domain Vehicles

Authors: Hanyue Shen, Jiaying Zhang, Xingwei Kong

Abstract:

Growing research on cross-domain vehicles (CDVs) has addressed the requirement to balance airfoil efficiency in air and water. No existing airfoil is specifically developed to adapt to the large Reynold’s number range CDVs operate in. This research proposes a supercritical airfoil biologically inspired by Atlantic Puffins. The initial airfoil is parameterized with the composite Karman-Trefftz method, optimized with a series of multi-stage gradient descend procedures, and compared with other airfoils with Xfoil. Results from Xfoil are also validated via Fluent and experiment considering curvatures on the designed airfoil might affect the accuracy of Xfoil. The results indicate that while CFD and Xfoil results closely align, Xfoil produces results closest to the experimental value. The bionic airfoil demonstrates superior performance in the range Re = 2·10⁴ to Re = 2·10⁵ compared to other studied airfoils, satisfying design requirements. This airfoil and its future counterparts are probable solutions to be implemented on fixed-wing CDVs desiring to glide in the given working conditions, providing an efficient and structurally simple pathway.

Keywords: fluid dynamics, airfoil design, biomimicry, cross domain vehicle

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1867 Empowerment at the Grassroots: Impact of Participatory (in) Equalities in Policy Formulation and Recognition and Redistribution of Women at the Grassroots in India

Authors: Samanwita Paul

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Borrowing from Kabeer’s framework of empowerment, participation of women at Panchayat level politics (grassroots level of politics in India) has been conceptualized as a resource in the study and the impact of the same in influencing the policies at the grassroots as an agency. The study attempts to examine such intricacies in the dynamics of participation and policy formulation at the Panchayat level and to assess its overall impact in altering the recognition and redistribution of women. A conscious attempt has been made to go beyond formal politics and consider participants of the informal political processes as subjects of the study. Primary surveys were conducted for data collection in 4 Panchayat villages (from Jalpaiguri district in West Bengal) of which 2 wards from each were selected based on the nature of reservation of the panchayat seats. In-depth interviews with the Panchayat members and an approximate of 80 voters from each of the villages were conducted. This has been further analyzed with the aid of appropriate statistical tools and narratives. Preliminary findings show that women from vulnerable sections tend to participate more in the political process since it offers them a means of negotiating with their vulnerabilities however in case of its impact on policy formulation, the effect of women’s participation does to appear to be as profound.

Keywords: recognition, redistribution, political participation, women

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1866 The Dynamics of Unsteady Squeezing Flow between Parallel Plates (Two-Dimensional)

Authors: Jiya Mohammed, Ibrahim Ismail Giwa

Abstract:

Unsteady squeezing flow of a viscous fluid between parallel plates is considered. The two plates are considered to be approaching each other symmetrically, causing the squeezing flow. Two-dimensional rectangular Cartesian coordinate is considered. The Navier-Stokes equation was reduced using similarity transformation to a single fourth order non-linear ordinary differential equation. The energy equation was transformed to a second order coupled differential equation. We obtained solution to the resulting ordinary differential equations via Homotopy Perturbation Method (HPM). HPM deforms a differential problem into a set of problem that are easier to solve and it produces analytic approximate expression in the form of an infinite power series by using only sixth and fifth terms for the velocity and temperature respectively. The results reveal that the proposed method is very effective and simple. Comparisons among present and existing solutions were provided and it is shown that the proposed method is in good agreement with Variation of Parameter Method (VPM). The effects of appropriate dimensionless parameters on the velocity profiles and temperature field are demonstrated with the aid of comprehensive graphs and tables.

Keywords: coupled differential equation, Homotopy Perturbation Method, plates, squeezing flow

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1865 HBTOnto: An Ontology Model for Analyzing Human Behavior Trajectories

Authors: Heba M. Wagih, Hoda M. O. Mokhtar

Abstract:

Social Network has recently played a significant role in both scientific and social communities. The growing adoption of social network applications has been a relevant source of information nowadays. Due to its popularity, several research trends are emerged to service the huge volume of users including, Location-Based Social Networks (LBSN), Recommendation Systems, Sentiment Analysis Applications, and many others. LBSNs applications are among the highly demanded applications that do not focus only on analyzing the spatiotemporal positions in a given raw trajectory but also on understanding the semantics behind the dynamics of the moving object. LBSNs are possible means of predicting human mobility based on users social ties as well as their spatial preferences. LBSNs rely on the efficient representation of users’ trajectories. Hence, traditional raw trajectory information is no longer convenient. In our research, we focus on studying human behavior trajectory which is the major pillar in location recommendation systems. In this paper, we propose an ontology design patterns with their underlying description logics to efficiently annotate human behavior trajectories.

Keywords: human behavior trajectory, location-based social network, ontology, social network

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1864 Towards a Rigorous Analysis for a Supercritical Particulate Process

Authors: Yousef Bakhbakhi

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Crystallization with supercritical fluids (SCFs), as a developed technology to produce particles of micron and sub-micron size with narrow size distribution, has found appreciable importance as an environmentally friendly technology. Particle synthesis using SCFs can be achieved employing a number of special processes involving solvent and antisolvent mechanisms. In this study, the compressed antisolvent (PCA) process is utilized as a model to analyze the theoretical complexity of crystallization with supercritical fluids. The population balance approach has proven to be an effectual technique to simulate and predict the particle size and size distribution. The nucleation and growth mechanisms of the particles formation in the PCA process is investigated using the population balance equation, which describes the evolution of the particle through coalescence and breakup levels with time. The employed mathematical population balance model contains a set of the partial differential equation with algebraic constraints, which demands a rigorous numerical approach. The combined Collocation and Galerkin finite element method are proposed as a high-resolution technique to solve the dynamics of the PCA process.

Keywords: particle formation, particle size and size distribution, PCA, supercritical carbon dioxide

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1863 Management of Urban Wastewater in the City of Maradi (Niger): The Case of Domestic Wastewater

Authors: Saidou Hassidou, Laminou Ary Mahaman Moustapha

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Uncontrolled urbanization of African cities, plus the lack of municipal waste management services in these cities, generate landscapes become places of multiple and varied interactions between health and environment. In this sense, under strong urban growth in a context of sub-equipment sanitation, the city of Maradi doesn’t escape to this situation which results in the spread of pollution (release of unpleasant odors, proliferation of mosquitoes) and many diseases posing multiple health problems. Our study focuses only on liquid waste especially domestic wastewater. To study the different domestic wastewater management options in the town of Maradi, a survey was conducted among 340 households in 17 districts. We note in most cases a crucial of waste management infrastructure (drainage and wastewater treatment) at the city. Thus, only the individual sanitation facilities are used. In the town of Maradi, in addition to the storm drains, there are, in old districts, ditches that discharge wastewater and unfortunately end up in rivers without treatment. Domestic wastewater total production is estimated at 86,761.28 m3 per day. This water is mostly from laundry activities, bathing, dishes, and is discharged in large part through the streets, by more than 60% of households. Also, pit emptying is performed at 39.11% by the vehicle Peugeot tank. The quality of service rendered by an actor is very important to encourage households to join. Existing autonomous sanitation facilities are poorly designed and poorly maintained. Fecal sludge is dumped in a hole near saturated latrines; this work is mainly done by manual scavengers or dumped in fields or on nearby vacant land concessions.

Keywords: management, urban wastewater, domestic wastewater, Maradi, Niger

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1862 A 3D Model of the Sustainable Management of the Natural Environment in National Parks

Authors: Paolo Russu

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This paper investigates the economic and ecological dynamics that emerge in Protected Areas (PAs) as a result of interactions between visitors to the area and the animals that live there. We suppose that the PAs contain two species whose interactions are determined by the Lotka-Volterra equations system. Visitors' decisions to visit PAs are influenced by the entrance cost required to enter the park as well as the chance of witnessing the species that live there. Visitors have contradictory effects on the species and thus on the sustainability of the protected areas: on the one hand, an increase in the number of tourists damages the natural habitat of the areas and thus the species living there; on the other hand, it increases the total amount of entrance fees that the managing body of the PAs can use to perform defensive expenditures that protect the species from extinction. For a given set of parameter values, the existence of saddle-node bifurcation, Hopf bifurcation, homoclinic orbits, and a Bogdanov–Takens bifurcation of codimension two has been investigated. The system displays periodic doubling and chaotic solutions, as demonstrated by numerical examples. Pontryagin's Maximum Principle was utilized to develop an optimal admission charge policy that maximized both social gain and ecosystem conservation.

Keywords: environmental preferences, singularities point, dynamical system, chaos

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1861 Exploring the Visual Roots of Classical Rhetoric and Its Implication for Gender Politics: Reflection upon Roman Rhetoric from a Bakhtin's Perspective

Authors: Hsiao-Yung Wang

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This study aims to explore the visual roots of classical rhetoric and its implication for gender politics by the constant reference to Mikhail Bakhtin’s theory of novelist time. First, it attempts to clarify the argument that “visuality always has been integral to rhetorical consciousness” by critically re-reading the rhetorical theories of roman rhetorician such as Cicero and Quintilian. Thereby, the vague clues of visuality would be realized from the so-called ‘five canons of rhetoric’ (invention, arrangement, style, memory, and delivery), which originally deriving from verbal and spoken rhetorical tradition. Drawing on Mikhail Bakhtin’s elaboration of novelist time in contrast to epic time, it addresses the specific timeline inherent in the dynamics of visual rhetoric involves the refusing the ‘absolute past’, the focusing on unfinalized contemporary reality, and the expecting for open future. Taking the primary visions of Taipei LGBT parade over the past 13 years as research cases, it mentions that visuality could not only activate the rhetorical functions of classical rhetoric, but also inspire gender politics in the contemporary era.

Keywords: classical rhetoric, gender politics, Mikhail Bakhtin, visuality

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1860 Influence of the Coarse-Graining Method on a DEM-CFD Simulation of a Pilot-Scale Gas Fluidized Bed

Authors: Theo Ndereyimana, Yann Dufresne, Micael Boulet, Stephane Moreau

Abstract:

The DEM (Discrete Element Method) is used a lot in the industry to simulate large-scale flows of particles; for instance, in a fluidized bed, it allows to predict of the trajectory of every particle. One of the main limits of the DEM is the computational time. The CGM (Coarse-Graining Method) has been developed to tackle this issue. The goal is to increase the size of the particle and, by this means, decrease the number of particles. The method leads to a reduction of the collision frequency due to the reduction of the number of particles. Multiple characteristics of the particle movement and the fluid flow - when there is a coupling between DEM and CFD (Computational Fluid Dynamics). The main characteristic that is impacted is the energy dissipation of the system, to regain the dissipation, an ADM (Additional Dissipative Mechanism) can be added to the model. The objective of this current work is to observe the influence of the choice of the ADM and the factor of coarse-graining on the numerical results. These results will be compared with experimental results of a fluidized bed and with a numerical model of the same fluidized bed without using the CGM. The numerical model is one of a 3D cylindrical fluidized bed with 9.6M Geldart B-type particles in a bubbling regime.

Keywords: additive dissipative mechanism, coarse-graining, discrete element method, fluidized bed

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1859 16s rRNA Based Metagenomic Analysis of Palm Sap Samples From Bangladesh

Authors: Ágota Ábrahám, Md Nurul Islam, Karimane Zeghbib, Gábor Kemenesi, Sazeda Akter

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Collecting palm sap as a food source is an everyday practice in some parts of the world. However, the consumption of palm juice has been associated with regular infections and epidemics in parts of Bangladesh. This is attributed to fruit-eating bats and other vertebrates or invertebrates native to the area, contaminating the food with their body secretions during the collection process. The frequent intake of palm juice, whether as a processed food product or in its unprocessed form, is a common phenomenon in large areas. The range of pathogens suitable for human infection resulting from this practice is not yet fully understood. Additionally, the high sugar content of the liquid makes it an ideal culture medium for certain bacteria, which can easily propagate and potentially harm consumers. Rapid diagnostics, especially in remote locations, could mitigate health risks associated with palm juice consumption. The primary objective of this research is the rapid genomic detection and risk assessment of bacteria that may cause infections in humans through the consumption of palm juice. Utilizing state-of-the-art third-generation Nanopore metagenomic sequencing technology based on 16S rRNA, and identified bacteria primarily involved in fermenting processes. The swift metagenomic analysis, coupled with the widespread availability and portability of Nanopore products (including real-time analysis options), proves advantageous for detecting harmful pathogens in food sources without relying on extensive industry resources and testing.

Keywords: raw date palm sap, NGS, metabarcoding, food safety

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1858 Optimizing the Effectiveness of Docetaxel with Solid Lipid Nanoparticles: Formulation, Characterization, in Vitro and in Vivo Assessment

Authors: Navid Mosallaei, Mahmoud Reza Jaafari, Mohammad Yahya Hanafi-Bojd, Shiva Golmohammadzadeh, Bizhan Malaekeh-Nikouei

Abstract:

Background: Docetaxel (DTX), a potent anticancer drug derived from the European yew tree, is effective against various human cancers by inhibiting microtubule depolymerization. Solid lipid nanoparticles (SLNs) have gained attention as drug carriers for enhancing drug effectiveness and safety. SLNs, submicron-sized lipid-based particles, can passively target tumors through the "enhanced permeability and retention" (EPR) effect, providing stability, drug protection, and controlled release while being biocompatible. Methods: The SLN formulation included biodegradable lipids (Compritol and Precirol), hydrogenated soy phosphatidylcholine (H-SPC) as a lipophilic co-surfactant, and Poloxamer 188 as a non-ionic polymeric stabilizer. Two SLN preparation techniques, probe sonication and microemulsion, were assessed. Characterization encompassed SLNs' morphology, particle size, zeta potential, matrix, and encapsulation efficacy. In-vitro cytotoxicity and cellular uptake studies were conducted using mouse colorectal (C-26) and human malignant melanoma (A-375) cell lines, comparing SLN-DTX with Taxotere®. In-vivo studies evaluated tumor inhibitory efficacy and survival in mice with colorectal (C-26) tumors, comparing SLNDTX withTaxotere®. Results: SLN-DTX demonstrated stability, with an average size of 180 nm and a low polydispersity index (PDI) of 0.2 and encapsulation efficacy of 98.0 ± 0.1%. Differential scanning calorimetry (DSC) suggested amorphous encapsulation of DTX within SLNs. In vitro studies revealed that SLN-DTX exhibited nearly equivalent cytotoxicity to Taxotere®, depending on concentration and exposure time. Cellular uptake studies demonstrated superior intracellular DTX accumulation with SLN-DTX. In a C-26 mouse model, SLN-DTX at 10 mg/kg outperformed Taxotere® at 10 and 20 mg/kg, with no significant differences in body weight changes and a remarkably high survival rate of 60%. Conclusion: This study concludes that SLN-DTX, prepared using the probe sonication, offers stability and enhanced therapeutic effects. It displayed almost same in vitro cytotoxicity to Taxotere® but showed superior cellular uptake. In a mouse model, SLN-DTX effectively inhibited tumor growth, with 10 mg/kg outperforming even 20 mg/kg of Taxotere®, without adverse body weight changes and with higher survival rates. This suggests that SLN-DTX has the potential to reduce adverse effects while maintaining or enhancing docetaxel's therapeutic profile, making it a promising drug delivery strategy suitable for industrialization.

Keywords: docetaxel, Taxotere®, solid lipid nanoparticles, enhanced permeability and retention effect, drug delivery, cancer chemotherapy, cytotoxicity, cellular uptake, tumor inhibition

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1857 Monthly River Flow Prediction Using a Nonlinear Prediction Method

Authors: N. H. Adenan, M. S. M. Noorani

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River flow prediction is an essential to ensure proper management of water resources can be optimally distribute water to consumers. This study presents an analysis and prediction by using nonlinear prediction method involving monthly river flow data in Tanjung Tualang from 1976 to 2006. Nonlinear prediction method involves the reconstruction of phase space and local linear approximation approach. The phase space reconstruction involves the reconstruction of one-dimensional (the observed 287 months of data) in a multidimensional phase space to reveal the dynamics of the system. Revenue of phase space reconstruction is used to predict the next 72 months. A comparison of prediction performance based on correlation coefficient (CC) and root mean square error (RMSE) have been employed to compare prediction performance for nonlinear prediction method, ARIMA and SVM. Prediction performance comparisons show the prediction results using nonlinear prediction method is better than ARIMA and SVM. Therefore, the result of this study could be used to developed an efficient water management system to optimize the allocation water resources.

Keywords: river flow, nonlinear prediction method, phase space, local linear approximation

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1856 Taxonomic Analyses of Some Members of Cucurbitoideae Using Phytolith Marker

Authors: J. K. Ebigwai, E. Asuquo

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Systematic affinities among Cucurbitaceae members are highly debatable as exemplified by diverging views on their phylogenies. Worst still is the overriding reliance on morphometric marker in the delimitation of cucurbitoideae members. Considerable symplesiomorphic and synapmorphic character states have been observed among some members of same genera than do with some members of other genera. The broad study aims at establishing phylogenies among species of Cucumis (Melothrieae), Momordica, Telfairia (Jolliffieae), Trichosanthes (Trichosantheae), Citrullus, Lagenaria, Luffa (Benincaseae) and Cucurbita (Cucurbita) using anatomical, cytological, Palynological, serological, and phytolith markers. However, this paper shall present preliminary findings on the phytolith character states for Cucumis melo, Momordica charantia, Telfairia occidentales, Trichosanthes dioica, Citrullus vulgaris, Lagenaria siceraria, Luffa cylindrical, Cucurbita pepo and Cucurbita maxima. Heavy liquid floatation method was employed in the extraction of the phytolith matter from the leaf tissues of these species. The result revealed that a bilobate short cell and a trapeziform sinuate form were absent in all the species except in Cucumis melo, Citrullus vulgaris and Lagenaria siceraria. Also a globular granulate form was observed exclusively in Telfairia occidentales, Cucurbita maxima, Momordica charantia and Luffa cylindrical. Other forms of phytolith observed were not diagnostic as they were not species specific. The results tentatively suggests a closer examination of the existing classification system.

Keywords: bilobate short cell, cucums, phytolith, telfairia, trapeziform sinuate

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1855 Simulation Model for Evaluating the Impact of Adaptive E-Learning in the Agricultural Sector

Authors: Maria Nabakooza

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Efficient agricultural production is very significant in attaining food sufficiency and security in the world. Many methods are employed by the farmers while attending to their gardens, from manual to mechanized, with Farmers range from subsistence to commercial depending on the motive. This creates a lacuna in the modes of operation in this field as different farmers will take different approaches. This has led to many e-Learning courses being introduced to address this gap. Many e-learning systems use advanced network technologies like Web services, grid computing to promote learning at any time and any place. Many of the existing systems have not inculcated the applicability of the modules in them, the tools to be used and further access whether they are the right tools for the right job. A thorough investigation into the applicability of adaptive eLearning in the agricultural sector has not been taken into account; enabling the assumption that eLearning is the right tool for boosting productivity in this sector. This study comes in to provide an insight and thorough analysis as to whether adaptive eLearning is the right tool for boosting agricultural productivity. The Simulation will adopt a system dynamics modeling approach as a way of examining causality and effect relationship. This study will provide teachers with an insight into which tools they should adopt in designing, and provide students the opportunities to achieve an orderly learning experience through adaptive navigating e-learning services.

Keywords: agriculture, adaptive, e-learning, technology

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1854 Effect of Season on Semen Production of Nubian and Saanen Bucks in Sudan

Authors: E. A. Babiker, S. A. Makawi

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The influence of the season (autumn, winter, and summer) on semen production in Nubian and Saanen bucks was studied. Seven mature bucks (4 Nubian and 3 Saanen) were used in this study to prepare semen samples which were collected with an artificial vagina. The samples were extended in Tris-egg yolk-glycerol-glucose extender, frozen, and stored in liquid nitrogen at –196 0C for 48 hours. Straws were thawed in water at –37 0C for 15 seconds before sperm evaluation (post-thaw sperm motility). There was a significant seasonal variation in both semen quantity (volume, concentration, and the total number of spermatozoa per ejaculate) and quality (percentage of sperm motility, percentage of post-thaw sperm motility, and dead spermatozoa). Greater ejaculate volumes were observed during summer and autumn in comparison to winter. Higher values of sperms concentration were observed during autumn, while the lowest sperm concentration values were observed during summer. Higher values of sperm motility were observed during autumn in comparison to summer. Lower values of dead spermatozoa were recorded during autumn, while the highest percentages of dead spermatozoa were observed during summer for the two breeds of bucks. The influence of season on post-thaw sperm motility was significant. Semen frozen during autumn and winter had the highest values, while during summer, lower mean values were observed. The best semen was produced during autumn and winter, while during summer, poor semen quality was recorded.

Keywords: season, Nubian, Saanen, semen production, Sudan

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1853 Study of Effect of Gear Tooth Accuracy on Transmission Mount Vibration

Authors: Kalyan Deepak Kolla, Ketan Paua, Rajkumar Bhagate

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Transmission dynamics occupy major role in customer perception of the product in both senses of touch and quality of sound. The quantity and quality of sound perceived is more concerned with the whine noise of the gears engaged. Whine noise is tonal in nature and tonal noises cause fatigue and irritation to customers, which in turn affect the quality of the product. Transmission error is the usual suspect for whine noise, which can be caused due to misalignments, tolerances, manufacturing variabilities. In-cabin noise is also more sensitive to the gear design. As the details of the gear tooth design and manufacturing are in microns, anything out of the tolerance zone, either in design or manufacturing, will cause a whine noise. This will also cause high variation in stress and deformation due to change in the load and leads to the fatigue failure of the gears. Hence gear design and development take priority in the transmission development process. This paper aims to study such variability by considering five pairs of helical spur gears and their effect on the transmission error, contact pattern and vibration level on the transmission.

Keywords: gears, whine noise, manufacturing variability, mount vibration variability

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1852 Synthesis of Nickel-Platinum Composite Nanoparticles and Silica-Coating of Them

Authors: Masato Yanase, Noriko Yamauchi, Shohei Tada, Yoshio Kobayashi

Abstract:

Nickel (Ni) and Ni-containing nanoparticles are promising materials due to their unique magnetic properties. In a preliminary experiment, aggregates of such nanoparticles formed after they were synthesized. Since the nanoparticle aggregation may deteriorate their unique properties, a method to suppress the nanoparticle aggregation has been required. In the present work, compositing with nickel (Ni) and platinum (Pt) and silica-coating of them were examined for suppression. Ni-Pt nanoparticles were synthesized in water exposed to air, in which nickel (II) acetate tetrahydrate, hexachloroplatinate (IV) hexahydrate, and sodium borohydride were used as a Ni source, a Pt source, and a reducing reagent, respectively. Polyvinylpyrrolidone, poly (sodium 4-styrene sulfonate), and citric acid were used as the stabilizers. Silica-coating of Ni-Pt nanoparticles was performed by adding tetraethylorthosilicate(TEOS)/ethanol solution to the Ni-Pt nanoparticle colloidal solution (Ni-Pt/SiO₂). The morphology of Ni-Pt nanoparticles was dependent on the reaction time and the species of stabilizer. The Ni-Pt/SiO₂ nanoparticles were composed of Ni-Pt nanoparticles as core and SiO₂ as shell, and their morphology depended on the TEOS concentrations. Furthermore, the Ni-Pt/SiO₂ nanoparticles were more dispersed compared to uncoated Ni-Pt nanoparticles. This suggested that the silica-coating had an effect on controlling the aggregation. The liquid-phase synthesis process involving the sol-gel method used in this study is advantageous for achieving monodispersion of particles and high-purity of materials. If the challenges of optimizing reaction conditions to achieve them during scale-up can be addressed, the proposed method holds great potential for large-scale production of particles in applications such as magnetic storage devices and biomedical imaging.

Keywords: metal, composite, nickel, platinum, nanoparticle, silica-coating

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1851 Dynamic Simulation for Surface Wear Prognosis of the Main Bearings in the Internal Combustion Engine

Authors: Yanyan Zhang, Ziyu Diao, Zhentao Liu, Ruidong Yan

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The wear character of the main bearing is one of the critical indicators for the overhaul of an internal combustion engine, and the aim of this paper is to reveal the dynamic wear mechanism of the main bearings. A numerical simulation model combined multi-body dynamic equations of the engine, the average Reynolds equations of the bearing lubricant, asperity contact and wear model of the joint surfaces were established under typical operating conditions. The wear results were verified by experimental data, and then the influence of operating conditions, bearing clearance and cylinder pressure on the wear character of selected main bearings were analyzed. The results show that the contribution degree of different working conditions on the wear profile and depth of each bearing is obviously different, and the increase of joint clearance or cylinder pressure will accelerate the wear. The numerical model presented can be used to wear prognosis for joints and provide guidance for optimization design of sliding bearings.

Keywords: dynamic simulation, multi-body dynamics, sliding bearing, surface wear

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1850 Simulation on Fuel Metering Unit Used for TurboShaft Engine Model

Authors: Bin Wang, Hengyu Ji, Zhifeng Ye

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Fuel Metering Unit (FMU) in fuel system of an aeroengine sometimes has direct influence on the engine performance, which is neglected for the sake of easy access to mathematical model of the engine in most cases. In order to verify the influence of FMU on an engine model, this paper presents a co-simulation of a stepping motor driven FMU (digital FMU) in a turboshaft aeroengine, using AMESim and MATLAB to obtain the steady and dynamic characteristics of the FMU. For this method, mechanical and hydraulic section of the unit is modeled through AMESim, while the stepping motor is mathematically modeled through MATLAB/Simulink. Combining these two sub-models yields an AMESim/MATLAB co-model of the FMU. A simplified component level model for the turboshaft engine is established and connected with the FMU model. Simulation results on the full model show that the engine model considering FMU characteristics describes the engine more precisely especially in its transition state. An FMU dynamics will cut down the rotation speed of the high pressure shaft and the inlet pressure of the combustor during the step response. The work in this paper reveals the impact of FMU on engine operation characteristics and provides a reference to an engine model for ground tests.

Keywords: fuel metering unit, stepping motor, AMESim/Matlab, full digital simulation

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1849 Invasion of Pectinatella magnifica in Freshwater Resources of the Czech Republic

Authors: J. Pazourek, K. Šmejkal, P. Kollár, J. Rajchard, J. Šinko, Z. Balounová, E. Vlková, H. Salmonová

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Pectinatella magnifica (Leidy, 1851) is an invasive freshwater animal that lives in colonies. A colony of Pectinatella magnifica (a gelatinous blob) can be up to several feet in diameter large and under favorable conditions it exhibits an extreme growth rate. Recently European countries around rivers of Elbe, Oder, Danube, Rhine and Vltava have confirmed invasion of Pectinatella magnifica, including freshwater reservoirs in South Bohemia (Czech Republic). Our project (Czech Science Foundation, GAČR P503/12/0337) is focused onto biology and chemistry of Pectinatella magnifica. We monitor the organism occurrence in selected South Bohemia ponds and sandpits during the last years, collecting information about physical properties of surrounding water, and sampling the colonies for various analyses (classification, maps of secondary metabolites, toxicity tests). Because the gelatinous matrix is during the colony lifetime also a host for algae, bacteria and cyanobacteria (co-habitants), in this contribution, we also applied a high performance liquid chromatography (HPLC) method for determination of potentially present cyanobacterial toxins (microcystin-LR, microcystin-RR, nodularin). Results from the last 3-year monitoring show that these toxins are under limit of detection (LOD), so that they do not represent a danger yet. The final goal of our study is to assess toxicity risks related to fresh water resources invaded by Pectinatella magnifica, and to understand the process of invasion, which can enable to control it.

Keywords: cyanobacteria, fresh water resources, Pectinatella magnifica invasion, toxicity monitoring

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1848 A Parametric Study on Aerodynamic Performance of Tyre Using CFD

Authors: Sowntharya L.

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Aerodynamics is the most important factor when it comes to resistive forces such as lift, drag and side forces acting on the vehicle. In passenger vehicles, reducing the drag will not only unlock the door for higher achievable speed but will also reduce the fuel consumption of the vehicle. Generally, tyre contributes significantly to the overall aerodynamics of the vehicle. Hence, understanding the air-flow behaviour around the tyre is vital to optimize the aerodynamic performance in the early stage of design process. Nowadays, aerodynamic simulation employing Computational Fluid Dynamics (CFD) is gaining more importance as it reduces the number of physical wind-tunnel experiments during vehicle development process. This research develops a methodology to predict aerodynamic drag of a standalone tyre using Numerical CFD Solver and to validate the same using a wind tunnel experiment. A parametric study was carried out on different tread pattern tyres such as slick, circumferential groove & patterned tyre in stationary and rotating boundary conditions. In order to represent wheel rotation contact with the ground, moving reference frame (MRF) approach was used in this study. Aerodynamic parameters such as drag lift & air flow behaviour around the tire were simulated and compared with experimental results.

Keywords: aerodynamics, CFD, drag, MRF, wind-tunnel

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1847 Understanding Parental Style and Its Effect on the Wellbeing of Adolescents with Epilepsy

Authors: Arthy Vinayakam, Emilda Judith Ezhil Rajan

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Adolescents with epilepsy living in developing country like India face many difficulties on stigma towards the disease. The psychological wellbeing of adolescents who are living with epilepsy has a varied influence on their daily activities and decision-making. Parental involvement with adolescents has always been a subject of caution. The dynamics in adolescents with epilepsy is much varied as their parental aspects has been known to have an impact on their education, socialization and wellbeing. The current study aims to identify the effect of parental styles, how they tend to effect the perception of self-concept that relate to the stigma in adolescents with epilepsy. A sample of 30 adolescents with epilepsy and their parents were taken; a control group of 30 adolescents and their parents were also taken. The General Health Questionnaire -12 was used as a screening for both groups to be included in the study. Parents were evaluated with Parenting Practices Questionnaire (PPQ). Adolescents were administered the Epilepsy Stigma Scale (ESS), Rosenberg Self-esteem Scale (RSS) and Adolescent Wellbeing Scale (AWS). Descriptive statistics was used to analyze the data. The findings of the study highlight the challenges of both parent and their influence on adolescent’s wellbeing. The findings also establish the impact of parenting style on the stigma in adolescents having epilepsy and how this influences their self-concept whereby their emotional strength.

Keywords: epilepsy, parenting style, stigma, wellbeing

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1846 Prediction of Trailing-Edge Noise under Adverse-Pressure Gradient Effect

Authors: Li Chen

Abstract:

For an aerofoil or hydrofoil in high Reynolds number flows, broadband noise is generated efficiently as the result of the turbulence convecting over the trailing edge. This noise can be related to the surface pressure fluctuations, which can be predicted by either CFD or empirical models. However, in reality, the aerofoil or hydrofoil often operates at an angle of attack. Under this situation, the flow is subjected to an Adverse-Pressure-Gradient (APG), and as a result, a flow separation may occur. This study is to assess trailing-edge noise models for such flows. In the present work, the trailing-edge noise from a 2D airfoil at 6 degree of angle of attach is investigated. Under this condition, the flow is experiencing a strong APG, and the flow separation occurs. The flow over the airfoil with a chord of 300 mm, equivalent to a Reynold Number 4x10⁵, is simulated using RANS with the SST k-ɛ turbulent model. The predicted surface pressure fluctuations are compared with the published experimental data and empirical models, and show a good agreement with the experimental data. The effect of the APG on the trailing edge noise is discussed, and the associated trailing edge noise is calculated.

Keywords: aero-acoustics, adverse-pressure gradient, computational fluid dynamics, trailing-edge noise

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1845 High Titer Cellulosic Ethanol Production Achieved by Fed-Batch Prehydrolysis Simultaneous Enzymatic Saccharification and Fermentation of Sulfite Pretreated Softwood

Authors: Chengyu Dong, Shao-Yuan Leu

Abstract:

Cellulosic ethanol production from lignocellulosic biomass can reduce our reliance on fossil fuel, mitigate climate change, and stimulate rural economic development. The relative low ethanol production (60 g/L) limits the economic viable of lignocellulose-based biorefinery. The ethanol production can be increased up to 80 g/L by removing nearly all the non-cellulosic materials, while the capital of the pretreatment process increased significantly. In this study, a fed-batch prehydrolysis simultaneously saccharification and fermentation process (PSSF) was designed to converse the sulfite pretreated softwood (~30% residual lignin) to high concentrations of ethanol (80 g/L). The liquefaction time of hydrolysis process was shortened down to 24 h by employing the fed-batch strategy. Washing out the spent liquor with water could eliminate the inhibition of the pretreatment spent liquor. However, the ethanol yield of lignocellulose was reduced as the fermentable sugars were also lost during the process. Fed-batch prehydrolyzing the while slurry (i.e. liquid plus solid fraction) pretreated softwood for 24 h followed by simultaneously saccharification and fermentation process at 28 °C can generate 80 g/L ethanol production. Fed-batch strategy is very effectively to eliminate the “solid effect” of the high gravity saccharification, so concentrating the cellulose to nearly 90% by the pretreatment process is not a necessary step to get high ethanol production. Detoxification of the pretreatment spent liquor caused the loss of sugar and reduced the ethanol yield consequently. The tolerance of yeast to inhibitors was better at 28 °C, therefore, reducing the temperature of the following fermentation process is a simple and valid method to produce high ethanol production.

Keywords: cellulosic ethanol, sulfite pretreatment, Fed batch PSSF, temperature

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1844 Management of Jebusaea hammerschmidtii and Batrachedra amydraula on Date Palm Trees in UAE

Authors: Mohammad Ali Al-Deeb, Hamda Ateeq Al Dhaheri

Abstract:

Insects cause major damage to crops and fruit trees worldwide. In the United Arab Emirates, the date palm tree is the most economically important tree which is used for date production as well as an ornamental tree. In 2002, the number of date palm trees in UAE was 40,700,000 and it is increasing over time. The longhorn stem borer (Jebusaea hammerschmidtii) and the lesser date month (Batrachedra amydraula) are important insect pests causing damage to date palm trees in UAE. Population dynamics of the Jebusaea hammerschmidtii and Batrachedra amydraula were studied by using light and pheromons traps, respectively in Al-Ain, UAE. The first trap catch of B. amydraula adults occurred on 19 April and the insect population peaked up on 26 April 2014. The first trap catch of J. hammerschmidtii occurred in April 2014. The numbers increased over time and the population peak occurred in June. The trapping was also done in 2015. The changes in insect numbers in relation to weather parameters are discussed. Also, the importance of the results on the management of these two pests is highlighted.

Keywords: date palm, integrated pest management, UAE, light trap, pheromone trap

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1843 Carbohydrate Intake Estimation in Type I Diabetic Patients Described by UVA/Padova Model

Authors: David A. Padilla, Rodolfo Villamizar

Abstract:

In recent years, closed loop control strategies have been developed in order to establish a healthy glucose profile in type 1 diabetic mellitus (T1DM) patients. However, the controller itself is unable to define a suitable reference trajectory for glucose. In this paper, a control strategy Is proposed where the shape of the reference trajectory is generated bases in the amount of carbohydrates present during the digestive process, due to the effect of carbohydrate intake. Since there no exists a sensor to measure the amount of carbohydrates consumed, an estimator is proposed. Thus this paper presents the entire process of designing a carbohydrate estimator, which allows estimate disturbance for a predictive controller (MPC) in a T1MD patient, the estimation will be used to establish a profile of reference and improve the response of the controller by providing the estimated information of ingested carbohydrates. The dynamics of the diabetic model used are due to the equations described by the UVA/Padova model of the T1DMS simulator, the system was developed and simulated in Simulink, taking into account the noise and limitations of the glucose control system actuators.

Keywords: estimation, glucose control, predictive controller, MPC, UVA/Padova

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1842 Analyzing the Market Growth in Application Programming Interface Economy Using Time-Evolving Model

Authors: Hiroki Yoshikai, Shin’ichi Arakawa, Tetsuya Takine, Masayuki Murata

Abstract:

API (Application Programming Interface) economy is expected to create new value by converting corporate services such as information processing and data provision into APIs and using these APIs to connect services. Understanding the dynamics of a market of API economy under the strategies of participants is crucial to fully maximize the values of the API economy. To capture the behavior of a market in which the number of participants changes over time, we present a time-evolving market model for a platform in which API providers who provide APIs to service providers participate in addition to service providers and consumers. Then, we use the market model to clarify the role API providers play in expanding market participants and forming ecosystems. The results show that the platform with API providers increased the number of market participants by 67% and decreased the cost to develop services by 25% compared to the platform without API providers. Furthermore, during the expansion phase of the market, it is found that the profits of participants are mostly the same when 70% of the revenue from consumers is distributed to service providers and API providers. It is also found that when the market is mature, the profits of the service provider and API provider will decrease significantly due to their competition, and the profit of the platform increases.

Keywords: API economy, ecosystem, platform, API providers

Procedia PDF Downloads 88
1841 Processing Methods for Increasing the Yield, Nutritional Value and Stability of Coconut Milk

Authors: Archana G. Lamdande, Shyam R. Garud, K. S. M. S. Raghavarao

Abstract:

Coconut has two edible parts, that is, a white kernel (solid endosperm) and coconut water (liquid endosperm). The white kernel is generally used in fresh or dried form for culinary purposes. Coconut testa, is the brown skin, covering the coconut kernel. It is removed by paring of wet coconut and obtained as a by-product in coconut processing industries during the production of products such as desiccated coconut, coconut milk, whole coconut milk powder and virgin coconut oil. At present, it is used as animal feed component after drying and recovering the residual oil (by expelling). Experiments were carried out on expelling of coconut milk for shredded coconut with and without testa removal, in order to explore the possibility of increasing the milk yield and value addition in terms of increased polyphenol content. The color characteristics of coconut milk obtained from the grating without removal of testa were observed to be L* 82.79, a* 0.0125, b* 6.245, while that obtained from grating with removal of testa were L* 83.24, a* -0.7925, b* 3.1. A significant increase was observed in total phenol content of coconut milk obtained from the grating with testa (833.8 µl/ml) when compared to that from without testa (521.3 µl/ml). However, significant difference was not observed in protein content of coconut milk obtained from the grating with and without testa (4.9 and 5.0% w/w, respectively). Coconut milk obtained from grating without removal of testa showed higher milk yield (62% w/w) when compared to that obtained from grating with removal of testa (60% w/w). The fat content in coconut milk was observed to be 32% (w/w), and it is unstable due to such a high fat content. Therefore, several experiments were carried out for examining its stability by adjusting the fat content at different levels (32, 28, 24, and 20% w/w). It was found that the coconut milk was more stable with a fat content of 24 % (w/w). Homogenization and ultrasonication and their combinations were used for exploring the possibility of increasing the stability of coconut milk. The microscopic study was carried out for analyzing the size of fat globules and the degree of their uniform distribution.

Keywords: coconut milk, homogenization, stability, testa, ultrasonication

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1840 Adult-Child Relationships: Nurturing Development and Well-Being

Authors: Obafemi Richard Jegede

Abstract:

The relationship between adults and children is pivotal for the social, emotional, and cognitive development of the latter. This paper explores the multifaceted dynamics of adult-child relationships, emphasizing their significance in fostering positive outcomes for children's well-being. It delves into dimensions such as attachment, communication, and parenting styles, addressing their impact on children's mental health and development. Furthermore, the role of supportive environments and interventions in enhancing adult-child relationships is examined. Understanding the complexities of these relationships is crucial for promoting healthy and nurturing interactions that contribute to children's holistic development. Positive interactions with caring adults promote children's self-regulation, empathy, and resilience, while negative or inconsistent relationships can lead to emotional distress and impaired social skills. Creating supportive environments that prioritize positive adult-child relationships is essential for promoting children's well-being. By comprehensively understanding the factors that shape adult-child relationships, we can better support children's development and well-being. This paper aims to provide insights into the complexities of adult-child relationships and their profound impact on children's development and overall well-being.

Keywords: impact on children's development, supportive environments and interventions, parenting style, communication between adult and children

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1839 Problems of Innovation Development of Wireless Data Transfer Branch in the Cellular Market of Kazakhstan

Authors: Yessengeldy Kuanyshpayev

Abstract:

Now in some countries of the world the cellular market is on the point of saturation, in others - positive dynamics of development kept on. The reasons for it are also different, but there are united by their general susceptibility to innovation changes, if they are really innovative. If to take as an example the cellular market of Kazakhstan it is defined by the low percent of smart phones at consumers, the low population density, undercapacity of the 3G channel, and absence of universal access to the LTE technology that limits dynamical growth of this branch. These moments are aggravated by failures of starting commercial projects by private companies which prevent to be implemented and widely adopted to a new product among consumers. The object of the research is possible integration of wireless and program technologies at which introduction the idea can regenerate in an innovation. The analysis of existing projects in the market and the possible union of the technologies through a prism of theoretical bases of innovative activity shows that efficiency of the company by development and introduction of innovations is possible only thanks to strict observance of all terms and conditions of the innovative process which main term is profit. Despite that fact that on a global scale the innovativeness issue of companies is very popular, there are no research about possibility of innovative breaks in the field of wireless access to the Internet in the cellular market of Kazakhstan.

Keywords: innovation, the effectiveness of company, commercialization, cellular market

Procedia PDF Downloads 389