Search results for: flow fields
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6696

Search results for: flow fields

2436 Fluorescence Resonance Energy Transfer in a Supramolecular Assembly of Luminescent Silver Nanoclusters and Cucurbit[8]uril Based Host-Guest System

Authors: Srikrishna Pramanik, Sree Chithra, Saurabh Rai, Sameeksha Agrawal, Debanggana Shil, Saptarshi Mukherjee

Abstract:

The understanding of interactions between organic chromophores and biologically useful luminescent noble metal nanoclusters (NCs) leading to an energy transfer process that has applications in light-harvesting materials is still in its nascent stage. This work describes a photoluminescent supramolecular assembly, made in two stages, employing an energy transfer process between silver (Ag) NCs as the donor and a host-guest system as the acceptor that can find potential applications in diverse fields. Initially, we explored the host-guest chemistry between a cationic guest, Ethidium Bromide and the anionic host Cucurbit[8]uril using spectroscopic and calorimetric techniques to decipher their interaction mechanism in modulating photophysical properties of the chromophore. Next, we synthesized a series of blue-emitting AgNCs using different templates such as protein, peptides, and cyclodextrin. The as-prepared AgNCs were characterized by various spectroscopic techniques. We have established that these AgNCs can be employed as donors in the FRET process with the above acceptor for FRET-based emission color tuning. Our in-depth studies revealed that surface ligands play a key role in modulating FRET efficiency. Overall, by employing a non-covalent strategy, we have tried to develop FRET pairs using blue-emitting NCs and a host-guest complex, which could find potential applications in constructing advanced white light-emitting, anti-counterfeiting materials, and developing biosensors.

Keywords: absorption spectroscopy, cavities, energy transfer, fluorescence, fluorescence resonance energy transfer

Procedia PDF Downloads 31
2435 Impact of E-Resources and Its Acceessability by Faculty and Research Scholars of Academic Libraries: A Case Study

Authors: M. Jaculine Mary

Abstract:

Today electronic resources are considered as an integral part of information sources to impart efficient services to the people aspiring to acquire knowledge in different fields. E-resources are those resources which include documents in e-format that can be accessed via the Internet in a digital library environment. The present study focuses on accessibility and use of e-resources by faculty and research scholars of academic libraries of Coimbatore, TamilNadu, India. The main objectives are to identify their purpose of using e-resources, know the users’ Information and Communication Technology (ICT) skills, identify satisfaction level of availability of e-resources, use of different e-resources, overall user satisfaction of using e-resources, impact of e-resources on their research and problems faced by them in the access of e-resources. The research methodology adopted to collect data for this study includes analysis of survey reports carried out by distributing questionnaires to the users. The findings of the research are based on the study of responses received from questionnaires distributed to a sample population of 200 users. Among the 200 respondents, 55 percent of research students and 45 percent of faculty members were users of e-resources. It was found that a majority of the users agreed that relevant, updated information at a fast pace had influenced them to use e-resources. Most of the respondents were of the view that more numbers of computers in the library would facilitate quick learning. Academic libraries have to take steps to arrange various training and orientation programmes for research students and faculty members to use the availability of e-resources. This study helps the librarian in planning and development of e-resources to provide modern services to their users of libraries. The study recommends that measures should be taken to increase the accessibility level of e-resource services among the information seekers for increasing the best usage of available electronic resources in the academic libraries.

Keywords: academic libraries, accessibility, electronic resources, satisfaction level, survey

Procedia PDF Downloads 132
2434 2D CFD-PBM Coupled Model of Particle Growth in an Industrial Gas Phase Fluidized Bed Polymerization Reactor

Authors: H. Kazemi Esfeh, V. Akbari, M. Ehdaei, T. N. G. Borhani, A. Shamiri, M. Najafi

Abstract:

In an industrial fluidized bed polymerization reactor, particle size distribution (PSD) plays a significant role in the reactor efficiency evaluation. The computational fluid dynamic (CFD) models coupled with population balance equation (CFD-PBM) have been extensively employed to investigate the flow behavior in the poly-disperse multiphase fluidized bed reactors (FBRs) utilizing ANSYS Fluent code. In this study, an existing CFD-PBM/ DQMOM coupled modeling framework has been used to highlight its potential to analyze the industrial-scale gas phase polymerization reactor. The predicted results reveal an acceptable agreement with the observed industrial data in terms of pressure drop and bed height. The simulated results also indicate that the higher particle growth rate can be achieved for bigger particles. Hence, the 2D CFD-PBM/DQMOM coupled model can be used as a reliable tool for analyzing and improving the design and operation of the gas phase polymerization FBRs.

Keywords: computational fluid dynamics, population balance equation, fluidized bed polymerization reactor, direct quadrature method of moments

Procedia PDF Downloads 356
2433 Microwave-Assisted 3D Porous Graphene for Its Multi-Functionalities

Authors: Jung-Hwan Oh, Rajesh Kumar, Il-Kwon Oh

Abstract:

Porous graphene has extensive potential applications in variety of fields such as hydrogen storage, CO oxidation, gas separation, supercapacitors, fuel cells, nanoelectronics, oil adsorption, and so on. However, the generation of some carbon atoms vacancies for precise small holes have been not extensively studied to prevent the agglomerates of graphene sheets and to obtain porous graphene with high surface area. Recently, many research efforts have been presented to develop physical and chemical synthetic approaches for porous graphene. But physical method has very high cost of manufacture and chemical method consumes so many hours for porous graphene. Herein, we propose a porous graphene contained holes with atomic scale precision by embedding metal nano-particles through microwave irradiation for hydrogen storage and CO oxidation multi- functionalities. This proposed synthetic method is appropriate for fast and convenient production of three dimensional nanostructures, which have nanoholes on the graphene surface in consequence of microwave irradiation. The metal nanoparticles are dispersed quickly on the graphene surface and generated uniform nanoholes on the graphene nanosheets. The morphological and structural characterization of the porous graphene were examined by scanning electron microscopy (SEM), transmission scanning electron microscopy (TEM) and RAMAN spectroscopy, respectively. The metal nanoparticle-embedded porous graphene exhibits a microporous volume of 2.586cm3g-1 with an average pore radius of 0.75 nm. HR-TEM analysis was carried out to further characterize the microstructures. By investigating the RAMAN spectra, we can understand the structural changes of graphene. The results of this work demonstrate a possibility to produce a new class of porous graphene. Furthermore, the newly acquired knowledge for the diffusion into graphene can provide useful guidance for the development of the growth of nanostructure.

Keywords: CO oxidation, hydrogen storage, nanocomposites, porous graphene

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2432 Oil Recovery Study by Low Temperature Carbon Dioxide Injection in High-Pressure High-Temperature Micromodels

Authors: Zakaria Hamdi, Mariyamni Awang

Abstract:

For the past decades, CO2 flooding has been used as a successful method for enhanced oil recovery (EOR). However, high mobility ratio and fingering effect are considered as important drawbacka of this process. Low temperature injection of CO2 into high temperature reservoirs may improve the oil recovery, but simulating multiphase flow in the non-isothermal medium is difficult, and commercial simulators are very unstable in these conditions. Furthermore, to best of authors’ knowledge, no experimental work was done to verify the results of the simulations and to understand the pore-scale process. In this paper, we present results of investigations on injection of low temperature CO2 into a high-pressure high-temperature micromodel with injection temperature range from 34 to 75 °F. Effect of temperature and saturation changes of different fluids are measured in each case. The results prove the proposed method. The injection of CO2 at low temperatures increased the oil recovery in high temperature reservoirs significantly. Also, CO2 rich phases available in the high temperature system can affect the oil recovery through the better sweep of the oil which is initially caused by penetration of LCO2 inside the system. Furthermore, no unfavorable effect was detected using this method. Low temperature CO2 is proposed to be used as early as secondary recovery.

Keywords: enhanced oil recovery, CO₂ flooding, micromodel studies, miscible flooding

Procedia PDF Downloads 341
2431 Pre-conditioning and Hot Water Sanitization of Reverse Osmosis Membrane for Medical Water Production

Authors: Supriyo Das, Elbir Jove, Ajay Singh, Sophie Corbet, Noel Carr, Martin Deetz

Abstract:

Water is a critical commodity in the healthcare and medical field. The utility of medical-grade water spans from washing surgical equipment, drug preparation to the key element of life-saving therapy such as hydrotherapy and hemodialysis for patients. A properly treated medical water reduces the bioburden load and mitigates the risk of infection, ensuring patient safety. However, any compromised condition during the production of medical-grade water can create a favorable environment for microbial growth putting patient safety at high risk. Therefore, proper upstream treatment of the medical water is essential before its application in healthcare, pharma and medical space. Reverse Osmosis (RO) is one of the most preferred treatments within healthcare industries and is recommended by all International Pharmacopeias to achieve the quality level demanded by global regulatory bodies. The RO process can remove up to 99.5% of constituents from feed water sources, eliminating bacteria, proteins and particles sizes of 100 Dalton and above. The combination of RO with other downstream water treatment technologies such as Electrodeionization and Ultrafiltration meet the quality requirements of various pharmacopeia monographs to produce highly purified water or water for injection for medical use. In the reverse osmosis process, the water from a liquid with a high concentration of dissolved solids is forced to flow through an especially engineered semi-permeable membrane to the low concentration side, resulting in high-quality grade water. However, these specially engineered RO membranes need to be sanitized either chemically or at high temperatures at regular intervals to keep the bio-burden at the minimum required level. In this paper, we talk about Dupont´s FilmTec Heat Sanitizable Reverse Osmosis membrane (HSRO) for the production of medical-grade water. An HSRO element must be pre-conditioned prior to initial use by exposure to hot water (80°C-85°C) for its stable performance and to meet the manufacturer’s specifications. Without pre-conditioning, the membrane will show variations in feed pressure operations and salt rejection. The paper will discuss the critical variables of pre-conditioning steps that can affect the overall performance of the HSRO membrane and demonstrate the data to support the need for pre-conditioning of HSRO elements. Our preliminary data suggests that there can be up to 35 % reduction in flow due to initial heat treatment, which also positively affects the increase in salt rejection. The paper will go into detail about the fundamental understanding of the performance change of HSRO after the pre-conditioning step and its effect on the quality of medical water produced. The paper will also discuss another critical point, “regular hot water sanitization” of these HSRO membranes. Regular hot water sanitization (at 80°C-85°C) is necessary to keep the membrane bioburden free; however, it can negatively impact the performance of the membrane over time. We will demonstrate several data points on hot water sanitization using FilmTec HSRO elements and challenge its robustness to produce quality medical water. The last part of this paper will discuss the construction details of the FilmTec HSRO membrane and features that make it suitable to pre-condition and sanitize at high temperatures.

Keywords: heat sanitizable reverse osmosis, HSRO, medical water, hemodialysis water, water for Injection, pre-conditioning, heat sanitization

Procedia PDF Downloads 197
2430 Evaluation of Mechanical Behavior of Laser Cladding in Various Tilting Pad Bearing Materials

Authors: Si-Geun Choi, Hoon-Jae Park, Jung-Woo Cho, Jin-Ho Lim, Jin-Young Park, Joo-Young Oh, Jae-Il Jeong Seock-Sam Kim, Young Tae Cho, Chan Gyu Kim, Jong-Hyoung Kim

Abstract:

The tilting pad bearing is a kind of the fluid film bearing and it can contribute to the high speed and the high load performance compared to other bearings including the rolling element bearing. Furthermore, the tilting bearing has many advantages such as high stability at high-speed performance, long life, high damping, high impact resistance and low noise. Therefore, it mostly used in mid to large size turbomachines, despite the high price disadvantage. Recently, manufacture and process employing laser techniques advancing at a fast-growing rate in mechanical industry, the dissimilar metal weld process employing laser techniques is actively studied. Moreover, also, Industry fields try to apply for welding the white metal and the back metal using laser cladding method for high durability. Furthermore, it has followed that laser cladding method has a lot better bond strength, toughness, anti-abrasion and environment-friendly than centrifugal casting method through preceding research. Therefore, the laser cladding method has a lot better quality, cost reduction, eco-friendliness and permanence of technology than the centrifugal casting method or the gravity casting method. In this study, we compare the mechanical properties of different bearing materials by evaluating the behavior of laser cladding layer with various materials (i.e. SS400, SCM440, S20C) under the same parameters. Furthermore, we analyze the porosity of various tilting pad bearing materials which white metal treated on samples. SEM, EDS analysis and hardness tests of three materials are shown to understand the mechanical properties and tribological behavior. W/D ratio, surface roughness results with various materials are performed in this study.

Keywords: laser cladding, tilting pad bearing, white metal, mechanical properties

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2429 Application of Industrial Ergonomics in Vehicle Service System Design

Authors: Zhao Yu, Zhi-Nan Zhang

Abstract:

More and more interactive devices are used in the transportation service system. Our mobile phones, on-board computers, and Head-Up Displays (HUDs) can all be used as the tools of the in-car service system. People can access smart systems with different terminals such as mobile phones, computers, pads and even their cars and watches. Different forms of terminals bring the different quality of interaction by the various human-computer Interaction modes. The new interactive devices require good ergonomics design at each stage of the whole design process. According to the theory of human factors and ergonomics, this paper compared three types of interactive devices by four driving tasks. Forty-eight drivers were chosen to experience these three interactive devices (mobile phones, on-board computers, and HUDs) by a simulate driving process. The subjects evaluated ergonomics performance and subjective workload after the process. And subjects were encouraged to support suggestions for improving the interactive device. The result shows that different interactive devices have different advantages in driving tasks, especially in non-driving tasks such as information and entertainment fields. Compared with mobile phones and onboard groups, the HUD groups had shorter response times in most tasks. The tasks of slow-up and the emergency braking are less accurate than the performance of a control group, which may because the haptic feedback of these two tasks is harder to distinguish than the visual information. Simulated driving is also helpful in improving the design of in-vehicle interactive devices. The paper summarizes the ergonomics characteristics of three in-vehicle interactive devices. And the research provides a reference for the future design of in-vehicle interactive devices through an ergonomic approach to ensure a good interaction relationship between the driver and the in-vehicle service system.

Keywords: human factors, industrial ergonomics, transportation system, usability, vehicle user interface

Procedia PDF Downloads 125
2428 Comparison between Hardy-Cross Method and Water Software to Solve a Pipe Networking Design Problem for a Small Town

Authors: Ahmed Emad Ahmed, Zeyad Ahmed Hussein, Mohamed Salama Afifi, Ahmed Mohammed Eid

Abstract:

Water has a great importance in life. In order to deliver water from resources to the users, many procedures should be taken by the water engineers. One of the main procedures to deliver water to the community is by designing pressurizer pipe networks for water. The main aim of this work is to calculate the water demand of a small town and then design a simple water network to distribute water resources among the town with the smallest losses. Literature has been mentioned to cover the main point related to water distribution. Moreover, the methodology has introduced two approaches to solve the research problem, one by the iterative method of Hardy-cross and the other by water software Pipe Flow. The results have introduced two main designs to satisfy the same research requirements. Finally, the researchers have concluded that the use of water software provides more abilities and options for water engineers.

Keywords: looping pipe networks, hardy cross networks accuracy, relative error of hardy cross method

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2427 Post Occupancy Evaluation of the Green Office Building with Different Air-Conditioning Systems

Authors: Ziwei Huang, Jian Ge, Jie Shen, Jiantao Weng

Abstract:

Retrofitting of existing buildings plays a critical role to achieve sustainable development. This is being considered as one of the approaches to achieving sustainability in the built environment. In order to evaluate the different air-conditioning systems effectiveness and user satisfaction of the existing building which had transformed into green building effectively and accurately. This article takes the green office building in Zhejiang province, China as an example, analyzing the energy consumption, occupant satisfaction and indoor environment quality (IEQ) from the perspective of the thermal environment. This building is special because it combines ground source heat pump system and Variable Refrigerant Flow (VRF) air-conditioning system. Results showed that the ground source heat pump system(EUIa≈25.6) consumes more energy than VRF(EUIb≈23.8). In terms of a satisfaction survey, the use of the VRF air-conditioning was more satisfactory in temperature. However, the ground source heat pump is more satisfied in air quality.

Keywords: post-occupancy evaluation, green office building, air-conditioning systems, ground source heat pump system

Procedia PDF Downloads 189
2426 Predicting Stem Borer Density in Maize Using RapidEye Data and Generalized Linear Models

Authors: Elfatih M. Abdel-Rahman, Tobias Landmann, Richard Kyalo, George Ong’amo, Bruno Le Ru

Abstract:

Maize (Zea mays L.) is a major staple food crop in Africa, particularly in the eastern region of the continent. The maize growing area in Africa spans over 25 million ha and 84% of rural households in Africa cultivate maize mainly as a means to generate food and income. Average maize yields in Sub Saharan Africa are 1.4 t/ha as compared to global average of 2.5–3.9 t/ha due to biotic and abiotic constraints. Amongst the biotic production constraints in Africa, stem borers are the most injurious. In East Africa, yield losses due to stem borers are currently estimated between 12% to 40% of the total production. The objective of the present study was therefore to predict stem borer larvae density in maize fields using RapidEye reflectance data and generalized linear models (GLMs). RapidEye images were captured for a test site in Kenya (Machakos) in January and in February 2015. Stem borer larva numbers were modeled using GLMs assuming Poisson (Po) and negative binomial (NB) distributions with error with log arithmetic link. Root mean square error (RMSE) and ratio prediction to deviation (RPD) statistics were employed to assess the models performance using a leave one-out cross-validation approach. Results showed that NB models outperformed Po ones in all study sites. RMSE and RPD ranged between 0.95 and 2.70, and between 2.39 and 6.81, respectively. Overall, all models performed similar when used the January and the February image data. We conclude that reflectance data from RapidEye data can be used to estimate stem borer larvae density. The developed models could to improve decision making regarding controlling maize stem borers using various integrated pest management (IPM) protocols.

Keywords: maize, stem borers, density, RapidEye, GLM

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2425 On the Solution of Fractional-Order Dynamical Systems Endowed with Block Hybrid Methods

Authors: Kizito Ugochukwu Nwajeri

Abstract:

This paper presents a distinct approach to solving fractional dynamical systems using hybrid block methods (HBMs). Fractional calculus extends the concept of derivatives and integrals to non-integer orders and finds increasing application in fields such as physics, engineering, and finance. However, traditional numerical techniques often struggle to accurately capture the complex behaviors exhibited by these systems. To address this challenge, we develop HBMs that integrate single-step and multi-step methods, enabling the simultaneous computation of multiple solution points while maintaining high accuracy. Our approach employs polynomial interpolation and collocation techniques to derive a system of equations that effectively models the dynamics of fractional systems. We also directly incorporate boundary and initial conditions into the formulation, enhancing the stability and convergence properties of the numerical solution. An adaptive step-size mechanism is introduced to optimize performance based on the local behavior of the solution. Extensive numerical simulations are conducted to evaluate the proposed methods, demonstrating significant improvements in accuracy and efficiency compared to traditional numerical approaches. The results indicate that our hybrid block methods are robust and versatile, making them suitable for a wide range of applications involving fractional dynamical systems. This work contributes to the existing literature by providing an effective numerical framework for analyzing complex behaviors in fractional systems, thereby opening new avenues for research and practical implementation across various disciplines.

Keywords: fractional calculus, numerical simulation, stability and convergence, Adaptive step-size mechanism, collocation methods

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2424 Introduction of a Model of Students' Practice in Social Work Education: Case of Republic of Srpska

Authors: Vesna Šućur-Janjetović, Andrea Rakanović Radonjić

Abstract:

Department of Social Work of the Faculty of Political Sciences, University of Banja Luka is the only School of Social Work in the Republic of Srpska (entity of Bosnia and Herzegovina). This Department has been implementing students’ practice as mandatory module since it was established in year 2000. As of 2006, the University of Banja Luka initiated the transformation of the education system in accordance with the Bologna Agreement. The Department of Social Work adopted a new Curriculum that anticipated 120 hours of Students’ practice. After ten years, a new process of changing and improving the Curriculum has been initiated, and research was conducted, in order to meet both the needs of practice and academic standards in the field of social work education. From 2006-2016 students were evaluating their practice experience under the mentor’s supervision. These evaluations were subject to the evaluation process of current Curriculum, including students practice module. Additional research was designed in order to assess the opinions of certified mentors on specific aspects of students’ practice, the needs of practice and possibilities for improving the education for social workers. Special research instruments were designed for the purpose of this research. All mentors were graduated social works working in all fields where social work services are provided (social welfare sector, health, education, non-government sector etc.). The third dimension of the research was a qualitative analysis of curriculums of Schools of Social Work in the region of Southeast Europe. This paper represents the results of the research, conclusions and consequences that led towards the improvement of Students’ practice and Curriculum of the Department of Social Work. The new Model anticipates 300 hours of Students’ practice, divided in three years of study, with different and specific learning outcomes.

Keywords: curriculum, Republic of Srpska, social work education, students’ practice

Procedia PDF Downloads 259
2423 The Pressure Losses in the Model of Human Lungs

Authors: Michaela Chovancova, Pavel Niedoba

Abstract:

For the treatment of acute and chronic lung diseases it is preferred to deliver medicaments by inhalation. The drug is delivered directly to tracheobronchial tree. This way allows the given medicament to get directly into the place of action and it makes rapid onset of action and maximum efficiency. The transport of aerosol particles in the particular part of the lung is influenced by their size, anatomy of the lungs, breathing pattern and airway resistance. This article deals with calculation of airway resistance in the lung model of Horsfield. It solves the problem of determination of the pressure losses in bifurcation and thus defines the pressure drop at a given location in the bronchial tree. The obtained data will be used as boundary conditions for transport of aerosol particles in a central part of bronchial tree realized by Computational Fluid Dynamics (CFD) approach. The results obtained from CFD simulation will allow us to provide information on the required particle size and optimal inhalation technique for particle transport into particular part of the lung.

Keywords: human lungs, bronchial tree, pressure losses, airways resistance, flow, breathing

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2422 Dewatering of Brewery Sludge through the Use of Biopolymers

Authors: Audrey Smith, M. Saifur Rahaman

Abstract:

The waste crisis has become a global issue, forcing many industries to reconsider their disposal methods and environmental practices. Sludge is a form of waste created in many fields, which include water and wastewater, pulp and paper, as well as from breweries. The composition of this sludge differs between sources and can, therefore, have varying disposal methods or future applications. When looking at the brewery industry, it produces a significant amount of sludge with a high water content. In order to avoid landfilling, this waste can further be processed into a valuable material. Specifically, the sludge must undergo dewatering, a process which typically involves the addition of coagulants like aluminum sulfate or ferric chloride. These chemicals, however, limit the potential uses of the sludge since it will contain traces of metals. In this case, the desired outcome of the brewery sludge would be to produce animal feed; however, these conventional coagulants would add a toxic component to the sludge. The use of biopolymers like chitosan, which act as a coagulant, can be used to dewater brewery sludge while allowing it to be safe for animal consumption. Chitosan is also a by-product created by the shellfish processing industry and therefore reduces the environmental imprint since it involves using the waste from one industry to treat the waste from another. In order to prove the effectiveness of this biopolymer, experiments using jar-tests will be utilised to determine the optimal dosages and conditions, while variances of contaminants like ammonium will also be observed. The efficiency of chitosan can also be compared to other polysaccharides to determine which is best suited for this waste. Overall a significant separation has been achieved between the solid and liquid content of the waste during the coagulation-flocculation process when applying chitosan. This biopolymer can, therefore, be used to dewater brewery sludge such that it can be repurposed as animal feed. The use of biopolymers can also be applied to treat sludge from other industries, which can reduce the amount of waste produced and allow for more diverse options for reuse.

Keywords: animal feed, biopolymer, brewery sludge, chitosan

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2421 An Experimental Investigation on the Droplet Behavior Impacting a Hot Surface above the Leidenfrost Temperature

Authors: Khaleel Sami Hamdan, Dong-Eok Kim, Sang-Ki Moon

Abstract:

An appropriate model to predict the size of the droplets resulting from the break-up with the structures will help in a better understanding and modeling of the two-phase flow calculations in the simulation of a reactor core loss-of-coolant accident (LOCA). A droplet behavior impacting on a hot surface above the Leidenfrost temperature was investigated. Droplets of known size and velocity were impacted to an inclined plate of hot temperature, and the behavior of the droplets was observed by a high-speed camera. It was found that for droplets of Weber number higher than a certain value, the higher the Weber number of the droplet the smaller the secondary droplets. The COBRA-TF model over-predicted the measured secondary droplet sizes obtained by the present experiment. A simple model for the secondary droplet size was proposed using the mass conservation equation. The maximum spreading diameter of the droplets was also compared to previous correlations and a fairly good agreement was found. A better prediction of the heat transfer in the case of LOCA can be obtained with the presented model.

Keywords: break-up, droplet, impact, inclined hot plate, Leidenfrost temperature, LOCA

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2420 Pros and Cons of Nanoparticles on Health

Authors: Amber Shahi, Ayesha Tazeen, Abdus Samad, Shama Parveen

Abstract:

Nanoparticles (NPs) are tiny particles. According to the International Organization for Standardization, the size range of NPs is in the nanometer range (1-100 nm). They show distinct properties that are not shown by larger particles of the same material. NPs are currently being used in different fields due to their unique physicochemical nature. NPs are a boon for medical sciences, environmental sciences, electronics, and textile industries. However, there is growing concern about their potential adverse effects on human health. This poster presents a comprehensive review of the current literature on the pros and cons of NPs on human health. The poster will discuss the various types of interactions of NPs with biological systems. There are a number of beneficial uses of NPs in the field of health and environmental welfare. NPs are very useful in disease diagnosis, antimicrobial action, and the treatment of diseases like Alzheimer’s. They can also cross the blood-brain barrier, making them capable of treating brain diseases. Additionally, NPs can target specific tumors and be used for cancer treatment. To treat environmental health, NPs also act as catalytic converters to reduce pollution from the environment. On the other hand, NPs also have some negative impacts on the human body, such as being cytotoxic and genotoxic. They can also affect the reproductive system, such as the testis and ovary, and sexual behavior. The poster will further discuss the routes of exposure of NPs. The poster will conclude with a discussion of the current regulations and guidelines on the use of NPs in various applications. It will highlight the need for further research and the development of standardized toxicity testing methods to ensure the safe use of NPs in various applications. When using NPs in diagnosis and treatment, we should also take into consideration their safe concentration in the body. Overall, this poster aims to provide a comprehensive overview of the pros and cons of NPs on human health and to promote awareness and understanding of the potential risks and benefits associated with their use.

Keywords: disease diagnosis, human health, nanoparticles, toxicity testing

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2419 Investigation of Boll Properties on Cotton Picker Machine Performance

Authors: Shahram Nowrouzieh, Abbas Rezaei Asl, Mohamad Ali Jafari

Abstract:

Cotton, as a strategic crop, plays an important role in providing human food and clothing need, because of its oil, protein, and fiber. Iran has been one of the largest cotton producers in the world in the past, but unfortunately, for economic reasons, its production is reduced now. One of the ways to reduce the cost of cotton production is to expand the mechanization of cotton harvesting. Iranian farmers do not accept the function of cotton harvesters. One reason for this lack of acceptance of cotton harvesting machines is the number of field losses on these machines. So, the majority of cotton fields are harvested by hand. Although the correct setting of the harvesting machine is very important in the cotton losses, the morphological properties of the cotton plant also affect the performance of cotton harvesters. In this study, the effect of some cotton morphological properties such as the height of the cotton plant, number, and length of sympodial and monopodial branches, boll dimensions, boll weight, number of carpels and bracts angle were evaluated on the performance of cotton picker. In this research, the efficiency of John Deere 9920 spindle Cotton picker is investigated on five different Iranian cotton cultivars. The results indicate that there was a significant difference between the five cultivars in terms of machine harvest efficiency. Golestan cultivar showed the best cotton harvester performance with an average of 87.6% of total harvestable seed cotton and Khorshid cultivar had the least cotton harvester performance. The principal component analysis showed that, at 50.76% probability, the cotton picker efficiency is affected by the bracts angle positively and by boll dimensions, the number of carpels and the height of cotton plants negatively. The seed cotton remains (in the plant and on the ground) after harvester in PCA scatter plot were in the same zone with boll dimensions and several carpels.

Keywords: cotton, bract, harvester, carpel

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2418 Development of Solar Energy Resources for Land along the Transportation Infrastructure: Taking the Lan-Xin Railway in the Silk Road Economic Belt as an Example

Authors: Dan Han, Yukun Zhang, Jie Zheng, Rui Zhang

Abstract:

Making full use of space along transportation infrastructure to develop renewable energy sources, especially solar energy resources, has become a research focus in relevant fields. In recent years, relevant international researches can be classified into three stages of theoretical and technical exploration, exploratory practice as well as planning implementation. Compared with traditional solar energy development mode, the development of solar energy resources in places along the transportation infrastructure has special advantages, which can also bring forth new opportunities for the development of green transportation. 'Road Integrated Photovoltaic', a development model of combining transport and new energy, has been actively studied and applied in developed countries, but it was still in its infancy in China. 'New Silk Road Economic Belt' has great advantage to carry out the 'Road Integrated Photovoltaic' because of the rich solar energy resources in its path, the shortages of renewable energy, the constraints of agricultural land and other reasons. Especially the massive amount of construction of transportation infrastructure brought by Silk Road Economic Belt, large area of developable land along the transportation line will be generated. Abundant solar energy recourses along the Silk Road will provide extremely superb practical opportunities to the land development along transportation infrastructure. We take PVsyst, GIS and Google map software for simulation of its potential by taking Lan-Xin Railway as an example, so potential electrical energy generation can be quantified and further analyzed. Research of 'New Silk Road Economic Belt' combined with 'Road Integrated Photovoltaic' is a creative development for the along transport and energy infrastructure. It not only can make full use of solar radiation and land in its path, but also bring more long-term advantages and benefits.

Keywords: land use, silk road economic belt, solar energy, transportation infrastructure

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2417 Magneto-Convective Instability in a Horizontal Power-Law Nanofluid Saturated Porous Layer

Authors: Norazuwin Najihah Mat Tahir, Fuziyah Ishak, Seripah Awang Kechil

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The onset of the convective instability in the horizontal through flow of a power-law nanofluid saturated by porous layer heated from below under the influences of magnetic field are investigated in this study. The linear stability theory is used for the transformation of the partial differential equations to system of ordinary differential equations through infinitesimal perturbations, scaling, linearization and method of normal modes with two-dimensional periodic waves. The system is solved analytically for the closed form solution of the Rayleigh number by using the Galerkin-type weighted residuals method to investigate the onset of both traveling wave and oscillatory convection. The effects of the power-law index, Lewis number and Peclet number on the stability of the system were investigated. The Lewis number stabilizes while the power-law index and Peclet number destabilize the nanofluid system. The system in the presence of magnetic field is more stable than the system in the absence of magnetic field.

Keywords: convection, instability, magnetic field, nanofluid, power-law

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2416 Effect of National Sovereignty of Non-Citizens Human Rights Standards: Mediterranean Irregular Immigrants Case

Authors: Azin Karami, Bahareh Heydari

Abstract:

There is a difference between national sovereignty ( national security guarantee) and human rights standards (human security guarantee). Under the pretext of providing security for the majority, Governments violate human rights standards and lead to populism. This paper illustrates despite the human rights standards of non-citizens, they mostly confront different practical and social realities. (a large gap between the reality and the truth). This paper has focused on one of vulnerable irregular non-citizens immigrants from Mediterranean . In addition, it has considered challenges of the basic and primary human rights standards of this group. It shows how government policies affect the flow of irregular immigration. This paper is based upon UN data about Mediterranean immigrants and polls answered by 68 people who intended to migrate from Mediterranean (28 female and 40 male people, the average age of 30 to 40). The model is supposed to be a convenient one to present objective, real evidence of irregular immigrants and discusses the challenges that this group of immigrants confront them .This paper shows clear concept of immigrants.

Keywords: human rights, human security, national sovereignty, irregular immigrants

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2415 Formulation of a Submicron Delivery System including a Platelet Lysate to Be Administered in Damaged Skin

Authors: Sergio A. Bernal-Chavez, Sergio Alcalá-Alcalá, Doris A. Cerecedo-Mercado, Adriana Ganem-Rondero

Abstract:

The prevalence of people with chronic wounds has increased dramatically by many factors including smoking, obesity and chronic diseases, such as diabetes, that can slow the healing process and increase the risk of becoming chronic. Because of this situation, the improvement of chronic wound treatments is a necessity, which has led to the scientific community to focus on improving the effectiveness of current therapies and the development of new treatments. The wound formation is a physiological complex process, which is characterized by an inflammatory stage with the presence of proinflammatory cells that create a proteolytic microenvironment during the healing process, which includes the degradation of important growth factors and cytokines. This decrease of growth factors and cytokines provides an interesting strategy for wound healing if they are administered externally. The use of nanometric drug delivery systems, such as polymer nanoparticles (NP), also offers an interesting alternative around dermal systems. An interesting strategy would be to propose a formulation based on a thermosensitive hydrogel loaded with polymeric nanoparticles that allows the inclusion and application of a platelet lysate (PL) on damaged skin, with the aim of promoting wound healing. In this work, NP were prepared by a double emulsion-solvent evaporation technique, using polylactic-co-glycolic acid (PLGA) as biodegradable polymer. Firstly, an aqueous solution of PL was emulsified into a PLGA organic solution, previously prepared in dichloromethane (DCM). Then, this disperse system (W/O) was poured into a polyvinyl alcohol (PVA) solution to get the double emulsion (W/O/W), finally the DCM was evaporated by magnetic stirring resulting in the NP formation containing PL. Once the NP were obtained, these systems were characterized by morphology, particle size, Z-potential, encapsulation efficiency (%EE), physical stability, infrared spectrum, calorimetric studies (DSC) and in vitro release profile. The optimized nanoparticles were included in a thermosensitive gel formulation of Pluronic® F-127. The gel was prepared by the cold method at 4 °C and 20% of polymer concentration. Viscosity, sol-gel phase transition, time of no flow solid-gel at wound temperature, changes in particle size by temperature-effect using dynamic light scattering (DLS), occlusive effect, gel degradation, infrared spectrum and micellar point by DSC were evaluated in all gel formulations. PLGA NP of 267 ± 10.5 nm and Z-potential of -29.1 ± 1 mV were obtained. TEM micrographs verified the size of NP and evidenced their spherical shape. The %EE for the system was around 99%. Thermograms and in infrared spectra mark the presence of PL in NP. The systems did not show significant changes in the parameters mentioned above, during the stability studies. Regarding the gel formulation, the transition sol-gel occurred at 28 °C with a time of no flow solid-gel of 7 min at 33°C (common wound temperature). Calorimetric, DLS and infrared studies corroborated the physical properties of a thermosensitive gel, such as the micellar point. In conclusion, the thermosensitive gel described in this work, contains therapeutic amounts of PL and fulfills the technological properties to be used in damaged skin, with potential application in wound healing and tissue regeneration.

Keywords: growth factors, polymeric nanoparticles, thermosensitive hydrogels, tissue regeneration

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2414 Comparison between Post- and Oxy-Combustion Systems in a Petroleum Refinery Unit Using Modeling and Optimization

Authors: Farooq A. Al-Sheikh, Ali Elkamel, William A. Anderson

Abstract:

A fluidized catalytic cracking unit (FCCU) is one of the effective units in many refineries. Modeling and optimization of FCCU were done by many researchers in past decades, but in this research, comparison between post- and oxy-combustion was studied in the regenerator-FCCU. Therefore, a simplified mathematical model was derived by doing mass/heat balances around both reactor and regenerator. A state space analysis was employed to show effects of the flow rates variables such as air, feed, spent catalyst, regenerated catalyst and flue gas on the output variables. The main aim of studying dynamic responses is to figure out the most influencing variables that affect both reactor/regenerator temperatures; also, finding the upper/lower limits of the influencing variables to ensure that temperatures of the reactors and regenerator work within normal operating conditions. Therefore, those values will be used as side constraints in the optimization technique to find appropriate operating regimes. The objective functions were modeled to be maximizing the energy in the reactor while minimizing the energy consumption in the regenerator. In conclusion, an oxy-combustion process can be used instead of a post-combustion one.

Keywords: FCCU modeling, optimization, oxy-combustion, post-combustion

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2413 Design and Development of Real-Time Optimal Energy Management System for Hybrid Electric Vehicles

Authors: Masood Roohi, Amir Taghavipour

Abstract:

This paper describes a strategy to develop an energy management system (EMS) for a charge-sustaining power-split hybrid electric vehicle. This kind of hybrid electric vehicles (HEVs) benefit from the advantages of both parallel and series architecture. However, it gets relatively more complicated to manage power flow between the battery and the engine optimally. The applied strategy in this paper is based on nonlinear model predictive control approach. First of all, an appropriate control-oriented model which was accurate enough and simple was derived. Towards utilization of this controller in real-time, the problem was solved off-line for a vast area of reference signals and initial conditions and stored the computed manipulated variables inside look-up tables. Look-up tables take a little amount of memory. Also, the computational load dramatically decreased, because to find required manipulated variables the controller just needed a simple interpolation between tables.

Keywords: hybrid electric vehicles, energy management system, nonlinear model predictive control, real-time

Procedia PDF Downloads 339
2412 Incorporating Multiple Supervised Learning Algorithms for Effective Intrusion Detection

Authors: Umar Albalawi, Sang C. Suh, Jinoh Kim

Abstract:

As internet continues to expand its usage with an enormous number of applications, cyber-threats have significantly increased accordingly. Thus, accurate detection of malicious traffic in a timely manner is a critical concern in today’s Internet for security. One approach for intrusion detection is to use Machine Learning (ML) techniques. Several methods based on ML algorithms have been introduced over the past years, but they are largely limited in terms of detection accuracy and/or time and space complexity to run. In this work, we present a novel method for intrusion detection that incorporates a set of supervised learning algorithms. The proposed technique provides high accuracy and outperforms existing techniques that simply utilizes a single learning method. In addition, our technique relies on partial flow information (rather than full information) for detection, and thus, it is light-weight and desirable for online operations with the property of early identification. With the mid-Atlantic CCDC intrusion dataset publicly available, we show that our proposed technique yields a high degree of detection rate over 99% with a very low false alarm rate (0.4%).

Keywords: intrusion detection, supervised learning, traffic classification, computer networks

Procedia PDF Downloads 339
2411 Women in Urban Agriculture: Institutional Challenges, COVID-19 and the War in Bahir Dar, Ethiopia

Authors: Meseret Gebeyehu Yehuala

Abstract:

Women represent the majority of urban farmers engaged in vegetable and fruit production in Bahir Dar, Ethiopia. We examine urban agriculture in Bahir Dar city in the context of disruptions caused by the civil war and COVID-19. The Sustainable Livelihoods Framework serves as a conceptual frame to explore the vulnerability context, the structural and institutional challenges faced by women, and how this impacts their livelihoods. A total of 25 urban women farmers and 6 key informants were involved in the study through explorative and structured interviews conducted in 2021. Observations and informal conversations during repeated visits provided deeper insights. In addition, key informants employed in civil service institutions and experts were interviewed. Data were analysed by applying qualitative content analysis by using Atlas tia software. Women report that they experience a lack of access to land, insecurity of tenure, irregular technical support and input provision by agricultural extension services, and lack of access to credit and formal marketplaces. The COVID-19 pandemic restrictions aggravated this situation by delaying agricultural extension offices’ provision of necessary inputs and disrupting food handling and storage leading to the loss of perishable products. Bombing in relation to the civil war has destroyed harvests and left women in fear of returning to their fields. Women stated that vegetable and fruit production could contribute to their incomes, household food supplies, and more diversified diets. However, the city municipal office has, so far, not committed to supporting urban agriculture as a livelihood strategy.

Keywords: urban agriculture, institutional challenges, Bahir Dar, sustainable livelihood framework

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2410 Experimental Investigation of Air Gap Membrane Distillation System with Heat Recovery

Authors: Yasser Elhenaw, A. Farag, Mohamed El-Ghandour, M. Shatat, G. H. Moustafa

Abstract:

This study investigates the performance of two spiral-wound Air Gap Membrane Distillation (AGMD) units. These units are connected in two different configurations in order to be tested and compared experimentally. In AGMD, the coolant water is used to condensate water vapor leaving membrane via condensing plate. The rejected cooling water has a relativity high temperature which can be used, depending on operation parameters, to increase the thermal efficiency and water productivity. In the first configuration, the seawater feed flows parallel and equally through both units then rejected. The coolant water is divided into the two units, and the heat source is divided into the two heat exchangers. In the second one, only the feed of the first unit is heated while the cooling rejected from the unit is used in heating the feed to the second. The performance of the system, estimated by the water productivity as well as the Gain Output Ratio (GOR), is measured for the two configurations at different feed flow rates, temperatures and salinities. The results show that at steady state condition, the heat recovery configurations lead to an increase in water productivity by 25%.

Keywords: membrane distillation, heat transfer, heat recovery, desalination

Procedia PDF Downloads 254
2409 Tool Condition Monitoring of Ceramic Inserted Tools in High Speed Machining through Image Processing

Authors: Javier A. Dominguez Caballero, Graeme A. Manson, Matthew B. Marshall

Abstract:

Cutting tools with ceramic inserts are often used in the process of machining many types of superalloy, mainly due to their high strength and thermal resistance. Nevertheless, during the cutting process, the plastic flow wear generated in these inserts enhances and propagates cracks due to high temperature and high mechanical stress. This leads to a very variable failure of the cutting tool. This article explores the relationship between the continuous wear that ceramic SiAlON (solid solutions based on the Si3N4 structure) inserts experience during a high-speed machining process and the evolution of sparks created during the same process. These sparks were analysed through pictures of the cutting process recorded using an SLR camera. Features relating to the intensity and area of the cutting sparks were extracted from the individual pictures using image processing techniques. These features were then related to the ceramic insert’s crater wear area.

Keywords: ceramic cutting tools, high speed machining, image processing, tool condition monitoring, tool wear

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2408 All-Optical Gamma-Rays and Positrons Source by Ultra-Intense Laser Irradiating an Al Cone

Authors: T. P. Yu, J. J. Liu, X. L. Zhu, Y. Yin, W. Q. Wang, J. M. Ouyang, F. Q. Shao

Abstract:

A strong electromagnetic field with E>1015V/m can be supplied by an intense laser such as ELI and HiPER in the near future. Exposing in such a strong laser field, laser-matter interaction enters into the near quantum electrodynamics (QED) regime and highly non-linear physics may occur during the laser-matter interaction. Recently, the multi-photon Breit-Wheeler (BW) process attracts increasing attention because it is capable to produce abundant positrons and it enhances the positron generation efficiency significantly. Here, we propose an all-optical scheme for bright gamma rays and dense positrons generation by irradiating a 1022 W/cm2 laser pulse onto an Al cone filled with near-critical-density plasmas. Two-dimensional (2D) QED particle-in-cell (PIC) simulations show that, the radiation damping force becomes large enough to compensate for the Lorentz force in the cone, causing radiation-reaction trapping of a dense electron bunch in the laser field. The trapped electrons oscillate in the laser electric field and emits high-energy gamma photons in two ways: (1) nonlinear Compton scattering due to the oscillation of electrons in the laser fields, and (2) Compton backwardscattering resulting from the bunch colliding with the reflected laser by the cone tip. The multi-photon Breit-Wheeler process is thus initiated and abundant electron-positron pairs are generated with a positron density ~1027m-3. The scheme is finally demonstrated by full 3D PIC simulations, which indicate the positron flux is up to 109. This compact gamma ray and positron source may have promising applications in future.

Keywords: BW process, electron-positron pairs, gamma rays emission, ultra-intense laser

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2407 The Minimum Age of Criminal Responsibility in the Philippines: Balancing International Standards and Domestic Concerns

Authors: Harold P. Pareja

Abstract:

This paper answers the question whether the minimum age of criminal responsibility under the Republic Act No. 9344 (Juvenile Justice Act) as amended by Republic Act No. 10630 should be lowered to 15 years of age or not in the light of international standards and domestic concerns both of which will definitely elicit strong views. It also explores the specific provision on the minimum age of criminal responsibility under the Republic Act No. 9344 (Juvenile Justice Act) and traces the bases of such law by discussing its presented evidences and justifications as reflected in the records of proceedings in the law-making phase. On one hand, the paper discusses the impact of lowering the minimum age to the state of juvenile delinquencies and to the rate of rehabilitation for those CICL who have undergone the DSWD-supervised recovery programs. On the other hand, it presents its impact to the international community specifically to the Committee of the Rights of the Child and the UNICEF considering that the even the current minimum age set in RA 9344 is lower than the international standards. Document review and content analysis are the major research tools. Primary and secondary sources were used as references such as Philippine laws on juvenile justice and from the different states international think-tanks. The absence of reliable evidences on criminal capacity made the arguments in increasing the MACR in the harder position. Studies on criminal capacity vary from different countries and from practitioners in in the fields of psychology, psychiatry and forensics. Juvenile delinquency is mainly contributed by poverty and dysfunctional families. On the other hand, the science of the criminal mind specifically among children has not been established yet. Philippines have the legal obligations to be faithful to the CRC and other related international instruments for the juvenile justice and welfare system. Decreasing MACR does not only send wrong message to the international community but the Philippines is violating its own laws.

Keywords: juvenile justice, minimum age of responsibility (MAR), juvenile justice act of the Philippines, children in conflict with the law, international standards on juvenile justice

Procedia PDF Downloads 390