Search results for: space applications
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9599

Search results for: space applications

3749 Controlling the Degradation Rate of Biodegradable Mg Implant Using Magnetron-Sputtered (Zr-Nb) Thin Films

Authors: Somayeh Azizi, Mohammad Hossein Ehsani, Amir Zareidoost

Abstract:

In this research, a technique has been developed to reduce the corrosion rate of magnesium (Mg) metal by creating Zr-Nb thin film coatings. In this regard, thin-film coatings of niobium (Nb) zirconium (Zr) double alloy are applied on pure Mg specimens under different processes conditions, such as the change of the substrate temperature, substrate bias, and coating thickness using the magnetron sputtering method. Then, deposited coatings are analyzed in terms of surface features via field-emission scanning electron microscopy (FE-SEM), thin-layer X-ray diffraction (GI-XRD), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), and corrosion tests. Also, nano-scratch tests were carried out to investigate the adhesion of the thin film. The results showed that the (Zr-Nb) thin films could control the degradation rate of Mg in the simulated body fluid (SBF). The nano-scratch studies depicted that the (Zr-Nb) thin films have a proper adhesion with the Mg substrate. Therefore, this technique could be used to enhance the corrosion resistance of bare Mg and could result in improving the performance of the biodegradable Mg implant for orthopedic applications.

Keywords: (Zr-Nb) thin film, magnetron sputtering, biodegradable Mg, degradation rate

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3748 Non-Contact Characterization of Standard Liquids Using Waveguide at 12.4 to18 Ghz Frequency Span

Authors: Kasra Khorsand-Kazemi, Bianca Vizcaino, Mandeep Chhajer Jain, Maryam Moradpour

Abstract:

This work presents an approach to characterize a non- contact microwave sensor using waveguides for different standard liquids such as ethanol, methanol and 2-propanol (Isopropyl Alcohol). Wideband waveguides operating between 12.4GHz to 18 GHz form the core of the sensing structure. Waveguides are sensitive to changes in conductivity of the sample under test (SUT), making them an ideal tool to characterize different polar liquids. As conductivity of the sample under test increase, the loss tangent of the material increase, thereby decreasing the S21 (dB) response of the waveguide. Among all the standard liquids measured, methanol exhibits the highest conductivity and 2-Propanol exhibits the lowest. The cutoff frequency measured for ethanol, 2-propanol, and methanol are 10.28 GHz, 10.32 GHz, and 10.38 GHz respectively. The measured results can be correlated with the loss tangent results of the standard liquid measured using the dielectric probe. This conclusively enables us to characterize different liquids using waveguides expanding the potential future applications in domains ranging from water quality management to bio-medical, chemistry and agriculture.

Keywords: Waveguides, , Microwave sensors, , Standard liquids characterization, Non-contact sensing

Procedia PDF Downloads 135
3747 Responsibility to Protect and State Sovereignty: The Case of Syria

Authors: Renu Kumari

Abstract:

State sovereignty refers to the ability and power of a state to be independent and not to have any interference of external actors in its internal affairs. This phenomenon has been accepted by International Law, which gives rights to the state to maintain its autonomy and territorial integrity without the interference of other actors. In of 1980’s and 1990’s the world has witnessed the worst case of human rights violence for instance, Rwanda genocide, the conflict in former Yugoslavia, Kosovo, Burundi, and Chad so and so forth. Though human rights violence is not a new phenomenon, it has been present all over the world in different time and space. But in 1990’s after the devastation of these conflicts and violence the world community came up with the notion of humanitarian intervention in which some states took the responsibility of protecting human rights violations and on the in order to protect they can intervene in the internal matters of a state specifically during civil war where state is unable to protect its people. Later on these so-called world community realized that intervention itself is a negative term that was criticized also therefore they came up with a different notion that sounded positive which known as responsibility to protect. In 2005 onwards, the notion of responsibility to protect accepted and recognized by the United Nations and states at a larger level. In the case of Syria on the name of responsibility to protect foreign interventions took place and due to the internal war Syrian people were already facing many problems, the government was not able to protect them. External invasion caused many devastating outcomes to the country. This paper is an attempt to analyze various dimensions of invasion of external affairs of a particular state and the status of sovereignty. Firstly, it lays out the notion of humanitarian intervention and then the responsibility to protect. Secondly, it looks in the case of Syria since 2011, the conflict of Syria. Thirdly it focuses on various efforts made by international organizations and other actors. Lastly, it looks why and how other actors intervene in the internal matter of Syria.

Keywords: state sovereignty, external actors, intervention, responsibility to protect

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3746 Health Promoting Properties of Phytochemicals from Rosemary (Rosmarinus officinalis) for Cancer and Inflammatory Bowel Disease

Authors: Jeremy J. Johnson

Abstract:

Mediterranean herbs including rosemary (Rosmarinus officinalis) contain a variety of phytochemicals including diterpenes that possess extensive biological activity. Applications of diterpenes, including the more abundant forms carnosol and carnosic acid, have been shown to possess anti-cancer, anti-inflammatory, anti-oxidant, and anti-proliferation properties. To confirm these properties, we have evaluated rosemary extract and selected diterpenes for biological activity in cancer and inflammatory models. Our preliminary data have revealed that select diterpenes can disrupt androgen receptor functionality in prostate and breast cancer cells. This property is unique among natural products for hormone-responsive cancers. The second area of interest has been evaluating rosemary extract and selected diterpenes for activation of sestrin-2, an antioxidant protein, in colon cancer cells. A combination of in vitro and in vivo approaches have been utilized to characterize the activity of rosemary diterpenes in rosemary. Taken together, these results suggest that phytochemicals found in rosemary have distinct pharmacological actions for disrupting cell-signaling pathways in cancer and inflammatory bowel disease.

Keywords: rosemary, diterpene, cancer, inflammation

Procedia PDF Downloads 139
3745 Transcriptome Analysis of Dry and Soaked Tomato (Solanum lycopersicum) Seeds in Response to Fast Neutron Irradiation

Authors: Yujie Zhou, Hee-Seong Byun, Sang-In Bak, Eui-Joon Kil, Kyung Joo Min, Vivek Chavan, Won Kyong Cho, Sukchan Lee, Seung-Woo Hong, Tae-Sun Park

Abstract:

Fast neutron irradiation (FNI) can cause mutations on plant genome but, in the most of cases, these irradiated plants have not shown significant characteristics phenotypically. In this study, we utilized RNA-Seq to generate a high-resolution transcriptome map of the tomato (Solanum lycopersicum) genome effected by FNI. To quantify the different transcription levels in tomato irradiated by FNI, tomato seeds were irradiated by using MC-50 cyclotron (KIRAMS, Korea) for 0, 30 and 90 minutes, respectively. To investigate the effects on the pre-soaking condition, experimental groups were divided into dry and soaked seeds, which were soaked for 8 hours before irradiation. There was no noticeable difference in the percentage germination (PG) among dry seeds, while irradiated soaked seeds have about 10 % lower PG compared to the unirradiated control group. Using whole transcriptome sequencing by HiSeq 2000, we analyzed the differential gene expression in response to different time of FNI in dry and soaked seeds. More than 1.4 million base pair reads were mapped onto the tomato reference genome and the expression pattern differences between irradiated and unirradiated seeds were assessed. In 0, 30 and 90 minutes irradiation, 12,135, 28,495 and 28,675 transcripts were generated, respectively. Gene ontology analysis suggested the different enrichment of transcripts involved in response to different FNI. The present study showed that FNI effects on plant gene expression, which can become a new parameters for evaluating the responses against FNI on plants. In addition, the comparative analysis of differentially expressed genes in D and S seeds by FNI will also give us a chance to deep explore novel candidate genes for FNI, which could be a good model system to understand the mechanisms behind the adaption of plant to space biology research.

Keywords: tomato (solanum lycopersicum), fast neutron irradiation, RNA-sequence, transcriptome expression

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3744 Deep Learning for Recommender System: Principles, Methods and Evaluation

Authors: Basiliyos Tilahun Betru, Charles Awono Onana, Bernabe Batchakui

Abstract:

Recommender systems have become increasingly popular in recent years, and are utilized in numerous areas. Nowadays many web services provide several information for users and recommender systems have been developed as critical element of these web applications to predict choice of preference and provide significant recommendations. With the help of the advantage of deep learning in modeling different types of data and due to the dynamic change of user preference, building a deep model can better understand users demand and further improve quality of recommendation. In this paper, deep neural network models for recommender system are evaluated. Most of deep neural network models in recommender system focus on the classical collaborative filtering user-item setting. Deep learning models demonstrated high level features of complex data can be learned instead of using metadata which can significantly improve accuracy of recommendation. Even though deep learning poses a great impact in various areas, applying the model to a recommender system have not been fully exploited and still a lot of improvements can be done both in collaborative and content-based approach while considering different contextual factors.

Keywords: big data, decision making, deep learning, recommender system

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3743 Sustainable Development Variables to Assess Transport Infrastructure in Remote Destinations

Authors: Dimitrios J. Dimitriou, Maria F. Sartzetaki

Abstract:

The assessment variables of the accessibility and the sustainability of access infrastructure for remote regions may vary significant by location and a wide range of factors may affect the decision process. In this paper, the environmental disturbance implications of transportation system to key demand and supply variables impact the economic system in remote destination are descripted. According to a systemic approach, the key sustainability variables deals with decision making process that have to be included in strategic plan for the critical transport infrastructure development and their relationship to regional socioeconomic system are presented. The application deals with the development of railway in remote destinations, where the traditional CBA not include the external cost generated by the environmental impacts that may have a range of diverse impacts on transport infrastructure and services. The analysis output provides key messages to decision and policy makers towards sustainable development of transport infrastructure, especially for remote destinations where accessibility is a key factor of regional economic development and social stability. The key conclusion could be essential useful for relevant applications in remote regions in the same latitude.

Keywords: sustainable development in remote regions, transport infrastructure, strategic planning, sustainability variables

Procedia PDF Downloads 344
3742 Application of Flexi-Wall in Noise Barriers Renewal

Authors: B. Daee, H. M. El Naggar

Abstract:

This paper presents an experimental study on structural performance of an innovative noise barrier consisting of poly-block, light polyurethane foam (LPF) and polyurea. This wall system (flexi-wall) is intended to be employed as a vertical extension to existing sound barriers in an accelerated construction method. To aid in the wall design, several mechanical tests were conducted on LPF specimens and two full-scale walls were then fabricated employing the same LPF material. The full-scale walls were subjected to lateral loading in order to establish their lateral resistance. A cyclic fatigue test was also performed on a full-scale flexi-wall in order to evaluate the performance of the wall under a repetitive loading condition. The result of the experiments indicated the suitability of flexi-wall in accelerated construction and confirmed that the structural performance of the wall system under lateral loading is satisfactory for the sound barrier application. The experimental results were discussed and a preliminary design procedure for application of flexi-wall in sound barrier applications was also developed.

Keywords: noise barrier, polyurethane foam, accelerated construction, full-scale experiment

Procedia PDF Downloads 287
3741 Robust ResNets for Chemically Reacting Flows

Authors: Randy Price, Harbir Antil, Rainald Löhner, Fumiya Togashi

Abstract:

Chemically reacting flows are common in engineering applications such as hypersonic flow, combustion, explosions, manufacturing process, and environmental assessments. The number of reactions in combustion simulations can exceed 100, making a large number of flow and combustion problems beyond the capabilities of current supercomputers. Motivated by this, deep neural networks (DNNs) will be introduced with the goal of eventually replacing the existing chemistry software packages with DNNs. The DNNs used in this paper are motivated by the Residual Neural Network (ResNet) architecture. In the continuum limit, ResNets become an optimization problem constrained by an ODE. Such a feature allows the use of ODE control techniques to enhance the DNNs. In this work, DNNs are constructed, which update the species un at the nᵗʰ timestep to uⁿ⁺¹ at the n+1ᵗʰ timestep. Parallel DNNs are trained for each species, taking in uⁿ as input and outputting one component of uⁿ⁺¹. These DNNs are applied to multiple species and reactions common in chemically reacting flows such as H₂-O₂ reactions. Experimental results show that the DNNs are able to accurately replicate the dynamics in various situations and in the presence of errors.

Keywords: chemical reacting flows, computational fluid dynamics, ODEs, residual neural networks, ResNets

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3740 Analysis and Suggestion on Patent Protection in Shanghai, China

Authors: Yuhong Niu, Na Li, Chunlin Jin, Hansheng Ding

Abstract:

The study reviewed all types of patents applied by Shanghai health system to analyze how patent development in China from the year of 1990 to 2012. The study used quantitative and comparative analysis to investigate the change and trends of patent numbers, patent types, patent claims, forward citations, patent life, patent transactions, etc. Results reflected an obviously increased numbers of invention patents, applications, and authorizations and short-life patents, but the ratio of invention patents represented an up and down change. Forward citations and transactions ratio always kept at a low level. The results meant that the protection of intellectual property in the Shanghai health sector had made great progress and lots of positive changes due to incentive policies by local government. However, the low-quality patents, at the same time, increased rapidly. Thus, in the future, it is suggested that the quality management should be strengthened, and invents should be estimated before patent application. It is also suggested that the incentives for intellectual property should be optimized to promote the comprehensive improvement of patent quantity and quality.

Keywords: patent claims, forward citations, patent life, patent transactions ratio

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3739 Structural and Electrical Properties of VO₂/ZnO Nanostructures

Authors: Sang-Wook Han, Zhenlan Jin, In-Hui Hwang, Chang-In Park

Abstract:

We examined structural and electrical properties of uniformly-oriented VO₂/ZnO nanostructures. VO₂ was deposited on ZnO templates by using a direct current-sputtering deposition. Scanning electron microscope and transmission electron microscope measurements indicated that b-oriented VO₂ were uniformly crystallized on ZnO templates with different lengths. VO₂/ZnO formed nanorods on ZnO nanorods with length longer than 250 nm. X-ray absorption fine structure at V K edge of VO₂/ZnO showed M1 and R phases of VO₂ at 30 and 100 ℃, respectively, suggesting structural phase transition between temperatures. Temperature-dependent resistance measurements of VO₂/ZnO nanostructures revealed metal-to-insulator transition at 65 ℃ and 55 ℃ during heating and cooling, respectively, regardless of ZnO length. The bond lengths of V-O and V-V pairs in VO₂/ZnO nanorods were somewhat distorted, and a substantial amount of structural disorder existed in the atomic pairs, compared to those of VO₂ films without ZnO. Resistance from VO₂/ZnO nanorods revealed a sharp MIT near 65 ℃ during heating and a hysteresis behavior. The resistance results suggest that microchannel for charge carriers exist nearly room temperature during cooling. VO₂/ZnO nanorods are quite stable and reproducible so that they can be widely used for practical applications to electronic devices, gas sensors, and ultra-fast switches, as examples.

Keywords: metal-to-insulator transition, VO₂, ZnO, XAFS, structural-phase transition

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3738 Preparation Non-Woven Nanofiber Structures for Uniform and Rapid Drug Releasing Applications Using an Electrospinning Process

Authors: Cho-Liang Chung

Abstract:

Uniform and rapid drug release are important for trauma dressing application. Low glass transition polymer system and non-woven nanofiber structures as the designs conduct rapid-release characteristics. In this study, polyvinylpyrrolidone, polysulfone, and polystyrene were dissolved in dimethylformamide to form precursor solution. These solutions were blended with vitamin C to form the electrospinning solutions. The non-woven nanofibers structures were successfully prepared using an electrospinning process. The following instruments were used to analyze the characteristics of non-woven nanofibers structures: Atomic force microscopy (AFM), Field Emission Scanning Electron Microscope (FE-SEM), and X-ray Diffraction (XRD). The AFM was used to scan the nanofibers. 3D Graphics were applied to explore the surface morphology of nanofibers. FE-SEM was used to explore the morphology of non-woven structures. XRD was used to identify crystal structures in the non-woven structures. The evolution of morphology of non-woven structures was changed dramatically in different durations, because of the moisture absorption and decreasing glass transition temperature; the non-woven nanofiber structures can be applied to uniform and rapid drug release for trauma dressing application.

Keywords: nanofibers, non-woven, electrospinning process, rapid drug releasing

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3737 Synthesis of Flower-Like Silver Nanoarchitectures in Special Shapes and Their Applications in Surface-Enhanced Raman Scattering

Authors: Radka Králová, Libor Kvítek, Václav Ranc, Aleš Panáček, Radek Zbořil

Abstract:

Surface–Enhanced Raman Scattering (SERS) is an optical spectroscopic technique with very good potential for sensitive detection of substances. In this research, active substrates with high enhancement were provided. Novel silver particles (nanostructures) with high roughened, flower–like morphology were prepared by reduction of cation complex [Ag(NH3)2]+ in presence of sodium borohydride as reducing agent and stabilized polyacrylic acid. The products were characterized by UV/VIS absorption spectrophotometry. Special shapes of silver particles were determined by scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM). Dispersions of this particle were put on fixed substrate to producing suitable layer for SERS. Adenine was applied as basic substance whose effect of enhancement on the layer of silver nanostructures was studied. By comparison with our work, the important influence of stabilizers, polyacrylic acid with various molecular weight and concentration, on the transfer of particles and formation of new structure was confirmed.

Keywords: metals, nanostructures, chemical reduction, Raman spectroscopy, optical properties

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3736 Aristotle University of Thessaloniki

Authors: Ail Akbar Emamverdian, Neriman Özada, Atabak Rahimzadeh Ilkhchi, Zahra Emamverdian

Abstract:

The reverse shoulder prosthesis is an innovative procedure design to treat of (GH) joint problems with severe rotator cuff deficiency. The original reverse shoulder prosthesis was invented by France surgery in1985 and has been in clinical use in the United States in 2004. These prostheses consist of baseplate that attached to the glenoid, in order to hold a spherical component, and humeral part consist of polyethylene insert which is flat. This prosthesis is the ‘reverse’ configuration. The indications for the reverse prosthesis are: (1) treating failed hemi arthroplasty with irrecoverable rotator cuff tears, (2) relief of painful arthritis associated with cuff tear arthropathy, (3) instauration after tumor resection, (4) pseudo paralysis because of irrecoverable rotator cuff tears (5) some fractures of the shoulder which reverse shoulder prostheses is only the option for treatment. This prosthesis resulting in relief of pain and decreasing the range of motion in above indications. However, this prosthesis and its applications such as notching of the scapula, dislocation of the prosthesis parts and acromial stress fractures. In this article the reverse shoulder prostheses, indication has been reviewed. This study can make clear aspect of reverse shoulder prosthesis that can help to find some solution in future.

Keywords: prostheses, complications, reverse shoulder prosthesis, indications

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3735 Hands-off Parking: Deep Learning Gesture-based System for Individuals with Mobility Needs

Authors: Javier Romera, Alberto Justo, Ignacio Fidalgo, Joshue Perez, Javier Araluce

Abstract:

Nowadays, individuals with mobility needs face a significant challenge when docking vehicles. In many cases, after parking, they encounter insufficient space to exit, leading to two undesired outcomes: either avoiding parking in that spot or settling for improperly placed vehicles. To address this issue, the following paper presents a parking control system employing gestural teleoperation. The system comprises three main phases: capturing body markers, interpreting gestures, and transmitting orders to the vehicle. The initial phase is centered around the MediaPipe framework, a versatile tool optimized for real-time gesture recognition. MediaPipe excels at detecting and tracing body markers, with a special emphasis on hand gestures. Hands detection is done by generating 21 reference points for each hand. Subsequently, after data capture, the project employs the MultiPerceptron Layer (MPL) for indepth gesture classification. This tandem of MediaPipe's extraction prowess and MPL's analytical capability ensures that human gestures are translated into actionable commands with high precision. Furthermore, the system has been trained and validated within a built-in dataset. To prove the domain adaptation, a framework based on the Robot Operating System (ROS), as a communication backbone, alongside CARLA Simulator, is used. Following successful simulations, the system is transitioned to a real-world platform, marking a significant milestone in the project. This real vehicle implementation verifies the practicality and efficiency of the system beyond theoretical constructs.

Keywords: gesture detection, mediapipe, multiperceptron layer, robot operating system

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3734 Implementing a Neural Network on a Low-Power and Mobile Cluster to Aide Drivers with Predictive AI for Traffic Behavior

Authors: Christopher Lama, Alix Rieser, Aleksandra Molchanova, Charles Thangaraj

Abstract:

New technologies like Tesla’s Dojo have made high-performance embedded computing more available. Although automobile computing has developed and benefited enormously from these more recent technologies, the costs are still high, prohibitively high in some cases for broader adaptation, particularly for the after-market and enthusiast markets. This project aims to implement a Raspberry Pi-based low-power (under one hundred Watts) highly mobile computing cluster for a neural network. The computing cluster built from off-the-shelf components is more affordable and, therefore, makes wider adoption possible. The paper describes the design of the neural network, Raspberry Pi-based cluster, and applications the cluster will run. The neural network will use input data from sensors and cameras to project a live view of the road state as the user drives. The neural network will be trained to predict traffic behavior and generate warnings when potentially dangerous situations are predicted. The significant outcomes of this study will be two folds, firstly, to implement and test the low-cost cluster, and secondly, to ascertain the effectiveness of the predictive AI implemented on the cluster.

Keywords: CS pedagogy, student research, cluster computing, machine learning

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3733 Urinalysis by Surface-Enhanced Raman Spectroscopy on Gold Nanoparticles for Different Disease

Authors: Leonardo C. Pacheco-Londoño, Nataly J. Galan-Freyle, Lisandro Pacheco-Lugo, Antonio Acosta, Elkin Navarro, Gustavo Aroca-Martínez, Karin Rondón-Payares, Samuel P. Hernández-Rivera

Abstract:

In our Life Science Research Center of the University Simon Bolivar (LSRC), one of the focuses is the diagnosis and prognosis of different diseases; we have been implementing the use of gold nanoparticles (Au-NPs) for various biomedical applications. In this case, Au-NPs were used for Surface-Enhanced Raman Spectroscopy (SERS) in different diseases' diagnostics, such as Lupus Nephritis (LN), hypertension (H), preeclampsia (PC), and others. This methodology is proposed for the diagnosis of each disease. First, good signals of the different metabolites by SERS were obtained through a mixture of urine samples and Au-NPs. Second, PLS-DA models based on SERS spectra to discriminate each disease were able to differentiate between sick and healthy patients with different diseases. Finally, the sensibility and specificity for the different models were determined in the order of 0.9. On the other hand, a second methodology was developed using machine learning models from all data of the different diseases, and, as a result, a discriminant spectral map of the diseases was generated. These studies were possible thanks to joint research between two university research centers and two health sector entities, and the patient samples were treated with ethical rigor and their consent.

Keywords: SERS, Raman, PLS-DA, diseases

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3732 Analyzing the Perception of Students and Faculty Members on Social Media Use in Academic Activities: A Case Study of Beijing Normal University

Authors: Mcjerry A. Bekoe, Emile Uwamahoro

Abstract:

Social media has become the order of the day, in particular among the youth. It is widely used both formally and informally in the university communities with varied definitions both in the academic circles and in the public domain. In simple terms, it is a media upon which social interactions are carried. In this work social media denote mobile phones, and web-base applications use by students and institutions to construct, partake, and distribute both existing and new information in a digital setting through internet communication. The basic aim of conducting this study was to analyze the perception of students and faculty members Beijing Normal University on social media use in the academic setting and to contribute to the understanding of how university students use social media, the advantages and disadvantages of social media in education. The study was qualitative and employed open-ended interview questions developed to seek students’ perception of the effects of social media and administered based on purposive sampling. Document analysis was also done because of triangulation to ensure validity and reliability. The results show there are positive and negative impacts of social media use depending on how one uses it. Social media have the capability to become a priceless asset to aid their educational communication.

Keywords: academics, high education, interactions, social media

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3731 Experimental Study and Numerical Simulation of the Reaction and Flow on the Membrane Wall of Entrained Flow Gasifier

Authors: Jianliang Xu, Zhenghua Dai, Zhongjie Shen, Haifeng Liu, Fuchen Wang

Abstract:

In an entrained flow gasifier, the combustible components are converted into the gas phase, and the mineral content is converted into ash. Most of the ash particles or droplets are deposited on the refractory or membrane wall and form a slag layer that flows down to the quenching system. The captured particle reaction process and slag flow and phase transformation play an important role in gasifier performance and safe and stable operation. The reaction characteristic of captured char particles on the molten slag had been studied by applied a high-temperature stage microscope. The gasification process of captured chars with CO2 on the slag surface was observed and recorded, compared to the original char gasification. The particle size evolution, heat transfer process are discussed, and the gasification reaction index of the capture char particle are modeled. Molten slag layer promoted the char reactivity from the analysis of reaction index, Coupled with heat transfer analysis, shrinking particle model (SPM) was applied and modified to predict the gasification time at carbon conversion of 0.9, and results showed an agreement with the experimental data. A comprehensive model with gas-particle-slag flow and reaction models was used to model the different industry gasifier. The carbon conversion information in the spatial space and slag layer surface are investigated. The slag flow characteristic, such as slag velocity, molten slag thickness, slag temperature distribution on the membrane wall and refractory brick are discussed.

Keywords: char, slag, numerical simulation, gasification, wall reaction, membrane wall

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3730 Investigation of the Dielectric Response of Ppy/V₂c Mxene-Zns from First Principle Calculation

Authors: Anthony Chidi Ezika, Gbolahan Joseph Adekoya, Emmanuel Rotimi Sadiku, Yskandar Hamam, Suprakas Sinha Ray

Abstract:

High-energy-density polymer/ceramic composites require a high breakdown strength and dielectric constant. Interface polarization and electric percolation are responsible for the high dielectric constant. In order to create composite dielectrics, high conductivity ceramic particles are combined with polymers to increase the dielectric constant. In this study, bonding and the non-uniform distribution of charges in the ceramic/ceramic interface zone are investigated using density functional theory (DFT) modeling. This non-uniform distribution of charges is intended to improve the ceramic/ceramic interface's dipole polarization (dielectric response). The interfacial chemical bond formation can also improve the structural stability of the hybrid filler and, consequently, of the composite films. To comprehend the electron-transfer process, the density of state and electron localization function of the PPy with hybrid fillers are also studied. The polymer nanocomposite is anticipated to provide a suitable dielectric response for energy storage applications.

Keywords: energy storage, V₂C/ ZnS hybrid, polypyrrole, MXene, nanocomposite, dielectric

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3729 Adsorptive Waste Heat Based Air-Conditioning Control Strategy for Automotives

Authors: Indrasen Raghupatruni, Michael Glora, Ralf Diekmann, Thomas Demmer

Abstract:

As the trend in automotive technology is fast moving towards hybridization and electrification to curb emissions as well as to improve the fuel efficiency, air-conditioning systems in passenger cars have not caught up with this trend and still remain as the major energy consumers amongst others. Adsorption based air-conditioning systems, e.g. with silica-gel water pair, which are already in use for residential and commercial applications, are now being considered as a technology leap once proven feasible for the passenger cars. In this paper we discuss a methodology, challenges and feasibility of implementing an adsorption based air-conditioning system in a passenger car utilizing the exhaust waste heat. We also propose an optimized control strategy with interfaces to the engine control unit of the vehicle for operating this system with reasonable efficiency supported by our simulation and validation results in a prototype vehicle, additionally comparing to existing implementations, simulation based as well as experimental. Finally we discuss the influence of start-stop and hybrid systems on the operation strategy of the adsorption air-conditioning system.

Keywords: adsorption air-conditioning, feasibility study, optimized control strategy, prototype vehicle

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3728 Modelling a Hospital as a Queueing Network: Analysis for Improving Performance

Authors: Emad Alenany, M. Adel El-Baz

Abstract:

In this paper, the flow of different classes of patients into a hospital is modelled and analyzed by using the queueing network analyzer (QNA) algorithm and discrete event simulation. Input data for QNA are the rate and variability parameters of the arrival and service times in addition to the number of servers in each facility. Patient flows mostly match real flow for a hospital in Egypt. Based on the analysis of the waiting times, two approaches are suggested for improving performance: Separating patients into service groups, and adopting different service policies for sequencing patients through hospital units. The separation of a specific group of patients, with higher performance target, to be served separately from the rest of patients requiring lower performance target, requires the same capacity while improves performance for the selected group of patients with higher target. Besides, it is shown that adopting the shortest processing time and shortest remaining processing time service policies among other tested policies would results in, respectively, 11.47% and 13.75% reduction in average waiting time relative to first come first served policy.

Keywords: queueing network, discrete-event simulation, health applications, SPT

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3727 Method of False Alarm Rate Control for Cyclic Redundancy Check-Aided List Decoding of Polar Codes

Authors: Dmitry Dikarev, Ajit Nimbalker, Alexei Davydov

Abstract:

Polar coding is a novel example of error correcting codes, which can achieve Shannon limit at block length N→∞ with log-linear complexity. Active research is being carried to adopt this theoretical concept for using in practical applications such as 5th generation wireless communication systems. Cyclic redundancy check (CRC) error detection code is broadly used in conjunction with successive cancellation list (SCL) decoding algorithm to improve finite-length polar code performance. However, there are two issues: increase of code block payload overhead by CRC bits and decrease of CRC error-detection capability. This paper proposes a method to control CRC overhead and false alarm rate of polar decoding. As shown in the computer simulations results, the proposed method provides the ability to use any set of CRC polynomials with any list size while maintaining the desired level of false alarm rate. This level of flexibility allows using polar codes in 5G New Radio standard.

Keywords: 5G New Radio, channel coding, cyclic redundancy check, list decoding, polar codes

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3726 Application of Costing System in the Small and Medium Sized Enterprises (SME) in Turkey

Authors: Hamide Özyürek, Metin Yılmaz

Abstract:

Standard processes, similar and limited production lines, the production of high direct costs will be more accurate than the use of parts of the traditional cost systems in the literature. However, direct costs, overhead expenses, in turn, decreases the burden of increasingly sophisticated production facilities, a situation that led the researchers to look for the cost of traditional systems of alternative techniques. Variety cost management approaches for example Total quality management (TQM), just-in-time (JIT), benchmarking, kaizen costing, targeting cost, life cycle costs (LLC), activity-based costing (ABC) value engineering have been introduced. Management and cost applications have changed over the past decade and will continue to change. Modern cost systems can provide relevant and accurate cost information. These methods provide the decisions about customer, product and process improvement. The aim of study is to describe and explain the adoption and application of costing systems in SME. This purpose reports on a survey conducted during 2014 small and medium sized enterprises (SME) in Ankara. The survey results were evaluated using SPSS package program.

Keywords: modern costing systems, managerial accounting, cost accounting, costing

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3725 Police Violence, Activism, and the Changing Rural United States: A Digital History and Mapping Narrative

Authors: Joel Zapata

Abstract:

Chicana/o Activism in the Southern Plains Through Time and Space, a digital history project available at PlainsMovement.com, helps reveal an understudied portion of the Chicana/o Civil Rights Movement: the way it unfolded on the Southern Plains. The project centers around an approachable interactive map and timeline along with a curated collection of materials. Therefore, the project provides a digital museum experience that has not emerged within the region’s museums. That is, this digital history project takes scholarly research to the wider public, making it is also a publicly facing history project. In this way, the project adds to both scholarly and socially significant conversations, showing that the region was home to a burgeoning wing of the Chicana/o Movement and that instances of police brutality largely spurred this wing of the social justice movement. Moreover, the curated collection of materials demonstrates that police brutality united the plains’ Mexican population across political ideology, a largely overlooked aspect within the study of Mexican American civil rights movements. Such a finding can be of use today since contemporary Latina/o social justice organizations generally ignore policing issues even amid a rise in national awareness regarding police abuse. In making history accessible to Mexican origin and Latina/o communities, these same communities may in-turn use the knowledge gained from historical research towards the betterment of their social positions—the foundational goal of Chicana/o history and the related field of Chicana/o Studies. Ultimately, this digital history project is intended to draw visitors to further explore the Chicana/o Civil Rights Movement within and beyond the plains.

Keywords: Chicana/o Movement, digital history, police brutality, newspapers, protests, student activism

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3724 Development of a Highly Flexible, Sensitive and Stretchable Polymer Nanocomposite for Strain Sensing

Authors: Shaghayegh Shajari, Mehdi Mahmoodi, Mahmood Rajabian, Uttandaraman Sundararaj, Les J. Sudak

Abstract:

Although several strain sensors based on carbon nanotubes (CNTs) have been reported, the stretchability and sensitivity of these sensors have remained as a challenge. Highly stretchable and sensitive strain sensors are in great demand for human motion monitoring and human-machine interface. This paper reports the fabrication and characterization of a new type of strain sensors based on a stretchable fluoropolymer / CNT nanocomposite system made via melt-mixing technique. Electrical and mechanical characterizations were obtained. The results showed that this nanocomposite sensor has high stretchability up to 280% of strain at an optimum level of filler concentration. The piezoresistive properties and the strain sensing mechanism of the strain sensor were investigated using Electrochemical Impedance Spectroscopy (EIS). High sensitivity was obtained (gauge factor as large as 12000 under 120% applied strain) in particular at the concentrations above the percolation threshold. Due to the tunneling effect, a non- linear piezoresistivity was observed at high concentrations of CNT loading. The nanocomposites with good conductivity and lightweight could be a promising candidate for strain sensing applications.

Keywords: carbon nanotubes, fluoropolymer, piezoresistive, strain sensor

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3723 Ozone Therapy for Disc Herniation: A Non-surgical Option

Authors: Shahzad Karim Bhatti

Abstract:

Background: Ozone is a combination of oxygen and can be used in treatment of low back pain due to herniated disc. It is a minimally invasive procedure using biochemical properties of ozone resulting in reduced volume of disc and inflammation resulting in significant pain relief. Aim: The purpose of this study was to evaluate the effectiveness of ozone therapy in combination with peri-ganglionic injection of local anesthetic and corticosteroid. Material and Methods: This retrospective study was done at the Interventional Radiology Department of Mayo Hospital, Lahore. A total of 49000 patients were included from January 2008 to March 2022. All the patients presented with clinical signs and symptoms of lumber disc herniation, which was confirmed by a MRI scan of the lumbar sacral spine. The pain reduction was calculated using modified MacNab method. All the patients underwent percutaneous injection of ozone at a concentration of 27 micrograms/ml to lumber disc under fluoroscopic guidance with combination of local anesthetic and corticosteroid in peri-ganglionic space. Results were evaluated by two expert observers who were blinded to patient treatment. Results A satisfactory therapeutic outcome was obtained. 55% of the patients showed complete recovery with resolution of symptoms. 20% of the patients complained of occasional episodic pain with no limitation of occupational activity. 15% of cases showed insufficient improvement. 5% of cases had insufficient improvement and went for surgery. 10% of cases never turned up after the first visit. Conclusion Intradiscal ozone for the treatment of herniated discs has revolutionized percutaneous approach to nerve root compression making it safer, economical and easier to repeat without any side effects than treatments currently used in Pakistan.

Keywords: pain, prolapse, Ozone, backpain

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3722 The Role of Flowering Pesticidal Plants for Sustainable Pest Management

Authors: Baltazar Ndakidemi

Abstract:

The resource-constrained farmers, especially those in sub-Saharan Africa, encounter significant challenges related to agriculture, notably diseases and pests. The sustainable means of pest management are not well known to farmers. As a result, some farmers use synthetic pesticides whose environmental impacts, ill health, and other negative impacts of synthetic pesticides on natural enemies have posed a great need for more sustainable means of pest management. Pesticidal plant resources can replace synthetic pesticides because their secondary metabolites can exhibit insecticidal activities such as deterrence, repellence, and pests' mortality. Additionally, the volatiles from these plants can have positive effects of attracting populations of natural enemies. Pesticidal plants can be grown as field margin plants or in strips for supporting natural enemies' populations. However, this is practically undetermined. Hence, there is a need to investigate the roles played by pesticidal plants in supporting natural enemies of pests and their applications in different cropping systems such as legumes. This study investigates different pesticidal plants with a high potential for pest control in agricultural fields. The information sheds light on potential plants that can be used for different crop pests.

Keywords: natural enemies, biological control, synthetic pesticides, pesticidal plants, predators, parasitoids

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3721 Investigation the Effect of Quenching Media on Abrasive Wear in Grade Medium Carbon Steel

Authors: Abbas S. Alwan, Waleed K. Hussan

Abstract:

In this paper, a general verification of possible heat treatment of steel has been done with the view of conditions of real abrasive wear of rotivater with soil texture. This technique is found promising to improve the quality of agriculture components working with the soil in dry condition. Abrasive wear resistance is very important in many applications and in most cases it is directly correlated with the hardness of materials surface. Responded of heat treatments were carried out in various media (Still air, Cottonseed oil, and Brine water 10 %) and follow by low-temperature tempering (250°C) was applied on steel type (AISI 1030). After heat treatment was applied wear with soil texture by using tillage process to determine the (actual wear rate) of the specimens depending on weight loss method. It was found; the wear resistance Increases with increase hardness with varying quenching media as follows; 30 HRC, 45 HRC, 52 HRC, and 60 HRC for nontreated (as received) cooling media as still air, cottonseed oil, and Brine water 10 %, respectively. Martensitic structure with retained austenite can be obtained depending on the quenching medium. Wear was presented on the worn surfaces of the steels which were used in this work.

Keywords: microstructures, hardness, abrasive wear, heat treatment, soil texture

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3720 Exploring the Application of Additive Manufacturing in the Production of Aerogels for the Purpose of Creating Environmentally Friendly Agricultural Formulations with Controlled Release Properties

Authors: Pram Abhayawardhana, Ali Reza Nazmi, Hossein Najaf Zadeh

Abstract:

This study examines the use of additive manufacturing (AM) to develop sustainable and intelligent agricultural formulations that can gradually release fertilisers. AM offers the ability to design customised formulations with precise geometries and controlled release properties while taking into account their mechanical, chemical, and environmental properties. The study specifically investigates the use of an aerogel matrix mixed with a potential fertiliser in agriculture. Highly porous 3D printed aerogel structures were designed to enable the slow release of fertilisers. The performance of the formulated mixture is evaluated against other commonly used materials for slow-release applications. The findings suggest that the 3D printed gel made has great potential for slow-release fertilisers, providing an environmentally friendly solution for agricultural practices. The combination of AM technology and sustainable materials can play a vital role in mitigating the negative environmental impact of traditional fertilisers, as well as improving the efficiency and sustainability of agricultural production.

Keywords: 3D printing, hydrogel, aerogel, fertiliser, agriculture

Procedia PDF Downloads 86