Search results for: four great elements
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6980

Search results for: four great elements

2450 Evaluation of the Discoloration of Methyl Orange Using Black Sand as Semiconductor through Photocatalytic Oxidation and Reduction

Authors: P. Acosta-Santamaría, A. Ibatá-Soto, A. López-Vásquez

Abstract:

Organic compounds in wastewaters coming from textile and pharmaceutical industry generated multiple harmful effects on the environment and the human health. One of them is the methyl orange (MeO), an azoic dye considered to be a recalcitrant compound. The heterogeneous photocatalysis emerges as an alternative for treating this type of hazardous compounds, through the generation of OH radicals using radiation and a semiconductor oxide. According to the author’s knowledge, catalysts such as TiO2 doped with metals show high efficiency in degrading MeO; however, this presents economic limitations on industrial scale. Black sand can be considered as a naturally doped catalyst because in its structure is common to find compounds such as titanium, iron and aluminum oxides, also elements such as zircon, cadmium, manganese, etc. This study reports the photocatalytic activity of the mineral black sand used as semiconductor in the discoloration of MeO by oxidation and reduction photocatalytic techniques. For this, magnetic composites from the mineral were prepared (RM, M1, M2 and NM) and their activity were tested through MeO discoloration while TiO2 was used as reference. For the fractions, chemical, morphological and structural characterizations were performed using Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM-EDX), X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) analysis. M2 fraction showed higher MeO discoloration (93%) in oxidation conditions at pH 2 and it could be due to the presence of ferric oxides. However, the best result to reduction process was using M1 fraction (20%) at pH 2, which contains a higher titanium percentage. In the first process, hydrogen peroxide (H2O2) was used as electron donor agent. According to the results, black sand mineral can be used as natural semiconductor in photocatalytic process. It could be considered as a photocatalyst precursor in such processes, due to its low cost and easy access.

Keywords: black sand mineral, methyl orange, oxidation, photocatalysis, reduction

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2449 Analysis of Practical Guidelines for Mobile Device Security in Indonesia Based on NIST SP 1800-4

Authors: Mardiyansyah Mardiyansyah, Hendrik Maulana, Eka Kurnia Sari, Imam Baehaki, Mohammad Agus Prihandono

Abstract:

Mobile device has become a key feature in Indonesian society and the economy, including government and private sector. Enterprises and government agencies already have a concern about mobile device security. However, small and medium enterprises (SME) do not have that sense yet, especially the new startups company. Indonesia has several laws, regulations, and standards for managing security in mobile devices. Currently, Indonesian information security policies have not been harmonized, each government organization and large enterprise has its own rules and policies. It leads to a conflict of interest among government agencies. This will certainly cause ineffectiveness in the implementation of policies. Therefore, an analysis of various government policies, regulations, and standards related to information security, especially on mobile devices, is carried out. This analysis is conducted to map the existing regulatory policies and standards into practical guidelines regarding NIST's information security to show the effectiveness of NIST SP 1800-4 towards existing policies. This work focused on the mapping of the NIST SP 1800-4 framework towards existing regulations, standards, and guidelines in Indonesia. The research approach is literature study to identify existing regulations, standards, and guidelines then the regulation mapped into the NIST SP 1800-4 framework and analyzed whether the framework could be applied to the organization in Indonesia. Finally, the finding and recommendations by documenting the security characteristics can be concluded. Based on the research finding, some of the regulations, standards, and guidelines in Indonesia are relevant to the elements in the NIST SP 1800-4 framework. From mapping analysis, the strength and weakness of mobile device security in Indonesia can be reported. It also can be concluded that the application of NIST SP 1800-4 can improve the effectiveness of mobile device security policies in Indonesia.

Keywords: mobile security, mobile security framework, NIST SP 1800-4, regulations

Procedia PDF Downloads 152
2448 Assessing the Cumulative Impact of PM₂.₅ Emissions from Power Plants by Using the Hybrid Air Quality Model and Evaluating the Contributing Salient Factor in South Taiwan

Authors: Jackson Simon Lusagalika, Lai Hsin-Chih, Dai Yu-Tung

Abstract:

Particles with an aerodynamic diameter of 2.5 meters or less are referred to as "fine particulate matter" (PM₂.₅) are easily inhaled and can go deeper into the lungs than other particles in the atmosphere, where it may have detrimental health consequences. In this study, we use a hybrid model that combined CMAQ and AERMOD as well as initial meteorological fields from the Weather Research and Forecasting (WRF) model to study the impact of power plant PM₂.₅ emissions in South Taiwan since it frequently experiences higher PM₂.₅ levels. A specific date of March 3, 2022, was chosen as a result of a power outage that prompted the bulk of power plants to shut down. In some way, it is not conceivable anywhere in the world to turn off the power for the sole purpose of doing research. Therefore, this catastrophe involving a power outage and the shutdown of power plants offers a great occasion to evaluate the impact of air pollution driven by this power sector. As a result, four numerical experiments were conducted in the study using the Continuous Emission Data System (CEMS), assuming that the power plants continued to function normally after the power outage. The hybrid model results revealed that power plants have a minor impact in the study region. However, we examined the accumulation of PM₂.₅ in the study and discovered that once the vortex at 925hPa was established and moved to the north of Taiwan's coast, the study region experienced higher observed PM₂.₅ concentrations influenced by meteorological factors. This study recommends that decision-makers take into account not only control techniques, specifically emission reductions, but also the atmospheric and meteorological implications for future investigations.

Keywords: PM₂.₅ concentration, powerplants, hybrid air quality model, CEMS, Vorticity

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2447 Integration Between Seismic Planning and Urban Planning for Improving the City Image of Tehran - Case of Tajrish

Authors: Samira Eskandari

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The image of Tehran has been impacted in recent years due to poor urban management and fragmented governance. There is no cohesive urban beautification framework in Tehran to enforce builders take aesthetic factors seriously when design and construct new buildings. The existing guidelines merely provide people with recommendations, not regulations. Obviously, Tehran needs a more comprehensive and strict urban beautification framework to restore its image. The damaged image has impacted the city’s social, economic and environmental growth. This research aims to find and examine a solution by which the employment of urban beautification regulation would be guaranteed, and city image would be organized. The methodology is based on a qualitative approach associated with analytical methods, in-depth surveys and interviews with Tehran citizens, authorities and experts, and use of academic resources as well as simulation. As a result, one practical solution is to incorporate aesthetic guidelines into a survival-related framework like a seismic guideline. Tehran is a seismic site, and all the buildings in Tehran have to be retrofitted against earthquake during construction. Hence, by integrating seismic regulations and aesthetic disciplines, urban beautification will be somehow guaranteed. Besides, the seismic image can turn into Tehran’s brand and enhances city identity. This research is trying to increase the social, environmental, and economic interconnectedness between urban planning and seismic planning by the usage of landscape architecture methods. As a case study, the potential outcomes are simulated in Tajrish, a suburb located in the north of Tehran. The result is that, by the redefinition of the morphology of seismic retrofitting systems, used in the significant city image elements, and re-function them in accordance with the Iranian culture and traditions, the city image would become more harmonized and legible.

Keywords: earthquake, retrofitting systems, Tehran image, urban beautification

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2446 Bifurcations of a System of Rotor-Ball Bearings with Waviness and Squeeze Film Dampers

Authors: Sina Modares Ahmadi, Mohamad Reza Ghazavi, Mandana Sheikhzad

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Squeeze film damper systems (SFD) are often used in machines with high rotational speed to reduce non-periodic behavior by creating external damping. These types of systems are frequently used in aircraft gas turbine engines. There are some structural parameters which are of great importance in designing these kinds of systems, such as oil film thickness, C, and outer race mass, mo. Moreover, there is a crucial parameter associated with manufacturing process, under the title of waviness. Geometric imperfections are often called waviness if its wavelength is much longer than Hertzian contact width which is a considerable source of vibration in ball bearings. In this paper, a system of a flexible rotor and two ball bearings with floating ring squeeze film dampers and consideration of waviness has been modeled and solved by a numerical integration method, namely Runge-Kutta method to investigate the dynamic response of the system. The results show that by increasing the number of wave lobes, which is due to inappropriate manufacturing, non- periodic and chaotic behavior increases. This result reveals the importance of manufacturing accuracy. Moreover, as long as C< 1.5×10-4 m, by increasing the oil film thickness, unwanted vibrations and non-periodic behavior of the system have been reduced, On the other hand, when C>1.5×10-4 m, increasing the outer oil film thickness results in the increasing chaotic and non-periodic responses. This result shows that although the presence of oil film results in reduction the non-periodic and chaotic behaviors, but the oil film has an optimal thickness. In addition, with increasing mo, the disc displacement amplitude increases. This result reveals the importance of utilizing light materials in manufacturing the squeeze film dampers.

Keywords: squeeze-film damper, waviness, ball bearing, bifurcation

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2445 Effect of Organophilic Clay on the Stability and Rheological Behavior of Oil-Based Drilling Muds

Authors: Hammadi Larbi

Abstract:

The major problem with oil-based drilling muds (reverse emulsions) is their thermodynamic instability and their high tendency to coalescence over time, irreversibly leading to destabilization. Water/Oil reverse emulsion drilling Muds are highly recommended when significant depths are reached. This study aimed to contribute experimentally to the knowledge of the structure (stability) and rheological behavior of drilling mud systems based on water/crude oil inverse emulsions through the investigation of the effect of organophilic clay. The chemical composition of organophilic clay such as VG69 shows a strong presence of silicon oxide (SiO2), followed by aluminum oxide (Al2O3), so these two elements are considered to be the main constituents of organophilic clays. The study also shows that the SiO2/Al2O3 ratio is equal to 3.52, which can be explained by the high content of free silica contained in the organophile clay used. The particle size analysis of the organophilic clays showed that the size of the of the particles analysed is in the range of 30 to 80 μm, this result ensures the correct particle size quality of organophilic clays and allows these powders to be used in Drilling mud systems.The experimental data of steady-state flow measurements are analyzed in the classic way by the Herschel-Bulkley model. Microscopic observation shows that the addition of quantities of organophilic clay type VG69 less than or equal to 3 g leading to the stability of the water/oil inverse emulsions, on the other hand, for quantities greater than 3 g, the emulsions are destabilized. The results obtained also showed that adding 3 g of organophilic clay to the crude oil drilling mud improves their stability by 70%.

Keywords: drilling muds, inverse emulsions, rheological behavior, yield stress, stability, organophilic clay

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2444 Building Safer Communities through Institutional Collaboration in Ghana: An Appraisal of Existing Arrangement

Authors: Louis Kusi Frimpong, Martin Oteng-Ababio

Abstract:

The problem of crime and insecurity in urban environments are often complex, multilayered, multidimensional and sometimes interwoven. It is from this perspective that recent approaches and strategies aimed at responding to crime and insecurity have looked at the problem from a social, economic, spatial and institutional point of view. In Ghana, there is much understanding of how various elements of the social and spatial setting influence crime and safety concerns of residents in urban areas. However, little research attention has been given to the institutional dimension of the problem of crime and insecurity in urban Ghana. In particular, scholars and policymakers in the area of safety and security have scarcely interrogated the forms of collaboration that exist between the various formal and informal institutions and how gaps and lapses in this collaboration influence vulnerability to crime and feelings of insecurity. Using Sekondi-Takoradi as a case study and drawing on both primary and secondary data, this paper assesses the activities of various institutions both formal and informal in crime control and prevention in the Sekondi-Takoradi metropolis, the third largest city in Ghana. More importantly, the paper seeks to address gaps in the institutional arrangement and coordination between and among institutions at the forefront of crime prevention efforts in the metropolis and by extension Ghanaian cities. The study found that whiles there is some form of collaboration between the police and the community, little collaboration existed between planning authorities and the police on the one hand, and the community on the other hand. The paper concludes that in light of the complex nature of a crime, institutional coordination and an inclusive approach involving formal and informal will be critical in promoting safer cities in Ghana.

Keywords: crime prevention, coordination, Ghana, institutional arrangement

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2443 Screening of Different Native Genotypes of Broadleaf Mustard against Different Diseases

Authors: Nisha Thapa, Ram Prasad Mainali, Prakriti Chand

Abstract:

Broadleaf mustard is a commercialized leafy vegetable of Nepal. However, its utilization is hindered in terms of production and productivity due to the high intensity of insects, pests, and diseases causing great loss. The plant protection part of the crop’s disease and damage intensity has not been studied much from research perspectives in Nepal. The research aimed to evaluate broadleaf mustard genotypes for resistance against different diseases. A total of 35 native genotypes of broadleaf mustard were screened at weekly intervals by scoring the plants for ten weeks. Five different diseases, such as Rhizoctonia root rot, Alternaria blight, black rot, turnip mosaic virus disease, and white rust, were reported from the broad leaf mustard genotypes. Out of 35 genotypes, 23 genotypes were found with very high Rhizoctonia Root Rot severity, whereas 8 genotypes showed very high Alternaria blight severity. Likewise, 3 genotypes were found with high Black rot severity, and 1 genotype was found with very high Turnip mosaic virus disease incidence. Similarly, 2 genotypes were found to have very high White rust severity. Among the disease of national importance, Rhizoctonia root rot was found to be the most severe disease with the greatest loss. Broadleaf mustard genotypes like Rato Rayo, CO 1002, and CO 11007 showed average to the high level of field resistance; therefore, these genotypes should be used, conserved, and stored in a mustard improvement program as the disease resistance quality or susceptibility of these genotypes can be helpful for seed producing farmers, companies and other stakeholders through varietal improvement and developmental works that further aids in sustainable disease management of the vegetable.

Keywords: genotype, disease resistance, Rhizoctonia root rot severity, varietal improvement

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2442 Educational Policies Vis-à-Vis Implementation and Challenges in the Case of Physically Disabled Children in Balochistan, Pakistan

Authors: Mumtaz Ali Baloch

Abstract:

This article aims at to review the policies and gaps including the socioeconomic and institutional factors that affected the enrollment of disabled children and caused drop-outs. It provides insights to scrutinize the gaps in policies, socioeconomic, and institutional factors with the specific concern in enrollment and drop out of disabled children in Pakistan, and Balochistan in particular. The findings of this study revealed that the old-age centralized policies and a number of socio-economic and institutional factors seemed to have significantly affected the enrollment and quality education in the case of physically disabled children. There were only a few schools functional in entire Balochistan. For example, an entire province (Balochistan) there are only two schools for disabled children, established in Quetta city. In the other 31 districts, an estimated population of 300,000 people of each district there were no schools for the disabled children. The findings of this study revealed that there is a great distinction between the policy and practice in the case of physically disabled children in Quetta, Balochistan. Consequently, such children seemed to have been out of schools. Dropout after the class eighth grade is almost 100%, as there are no high schools available for physically/disabled children, in Balochistan. The concerned organizations and authorities need to develop and ratify specific policies, provide required) facilities to the schools including sufficient budget, streamline the academic planning, and an effective monitoring and evaluation system. Only awareness and motivation could not help in improving the enrollment rate and decreasing the dropout in the case of physically disabled children. There is an urgent need to provide the required facilities to the schools. Almost all students needed assistive equipment, effective physical therapy as well as regular medical facilities. Such measures can improve the enrolment and rehabilitation of children.

Keywords: education policy, practices, physically disabled children, challenges, Balochistan, Pakistan

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2441 The Effectiveness of Using Picture Storybooks on Young English as a Foreign Language Learners for English Vocabulary Acquisition and Moral Education: A Case Study

Authors: Tiffany Yung Hsuan Ma

Abstract:

The Whole Language Approach, which gained prominence in the 1980s, and the increasing emphasis on multimodal resources in educational research have elevated the utilization of picture books in English as a foreign language (EFL) instruction. This approach underscores real-world language application, providing EFL learners with a range of sensory stimuli, including visual elements. Additionally, the substantial impact of picture books on fostering prosocial behaviors in children has garnered recognition. These narratives offer opportunities to impart essential values such as kindness, fairness, and respect. Examining how picture books enhance vocabulary acquisition can offer valuable insights for educators in devising engaging language activities conducive to a positive learning environment. This research entails a case study involving two kindergarten-aged EFL learners and employs qualitative methods, including worksheets, observations, and interviews with parents. It centers on three pivotal inquiries: (1) The extent of young learners' acquisition of essential vocabulary, (2) The influence of these books on their behavior at home, and (3) Effective teaching strategies for the seamless integration of picture storybooks into EFL instruction for young learners. The findings can provide guidance to parents, educators, curriculum developers, and policymakers regarding the advantages and optimal approaches to incorporating picture books into language instruction. Ultimately, this research has the potential to enhance English language learning outcomes and promote moral education within the Taiwanese EFL context.

Keywords: EFL, vocabulary acquisition, young learners, picture book, moral education

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2440 Public Policy as a Component of Entrepreneurship Ecosystems: Challenges of Implementation

Authors: José Batista de Souza Neto

Abstract:

This research project has as its theme the implementation of public policies to support micro and small businesses (MSEs). The research problem defined was how public policies for access to markets that drive the entrepreneurial ecosystem of MSEs are implemented. The general objective of this research is to understand the process of implementing a public policy to support the entrepreneurial ecosystem of MSEs by the Support Service for Micro and Small Enterprises of the State of São Paulo (SEBRAESP). Public policies are constituent elements of entrepreneurship ecosystems that influence the creation and development of ventures from the action of the entrepreneur. At the end of the research, it is expected to achieve the results for the following specific objectives: (a) understand how the entrepreneurial ecosystem of MSEs is constituted; (b) understand how market access public policies for MSEs are designed and implemented; (c) understand SEBRAE's role in the entrepreneurship ecosystem; and (d) offer an action plan and monitor its execution up to march, 2023. The field research will be conducted based on Action Research, with a qualitative and longitudinal approach to the data. Data collection will be based on narratives produced since 2019 when the decision to implement Comércio Brasil program, a public policy focused on generating market access for 4280 MSEs yearly, was made. The narratives will be analyzed by the method of document analysis and narrative analysis. It is expected that the research will consolidate the relevance of public policies to market access for MSEs and the role of SEBRAE as a protagonist in the implementation of these public policies in the entrepreneurship ecosystem will be demonstrated. Action research is recognized as an intervention method, it is expected that this research will corroborate its role in supporting management processes.

Keywords: entrepreneurship, entrepreneurship ecosystem, public policies, SEBRAE, action research

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2439 Adsorption of Dyes and Iodine: Reaching Outstanding Kinetics with CuII-Based Metal–Organic Nanoballs

Authors: Eder Amayuelas, Begoña Bazán, M. Karmele Urtiaga, Gotzone Barandika, María I. Arriortua

Abstract:

Metal Organic Frameworks (MOFs) have attracted great interest in recent years, taking a lead role in the field of catalysis, drug delivery, sensors and absorption. In the past decade, promising results have been reported specifically in the field of adsorption, based on the topology and chemical features of this type of porous material. Thus, its application in industry and environment for the adsorption of pollutants is presented as a response to an increasingly important need. In this area, organic dyes are nowadays widely used in many industries including medicine, textile, leather, printing and plastics. The consequence of this fact is that dyes are present as emerging pollutants in soils and water where they remain for long periods of time due to their high stability, with a potential risk of toxicity in wildlife and in humans. On the other hand, the presence of iodine in soils, water and gas as a nuclear activity pollutant product or its extended use as a germicide is still a problem in many countries, which indicates the imperative need for its removal. In this context, this work presents the characterization as an adsorbent of the activated compound αMOP@Ei2-1 obtained from the already reported [Cu₂₄(m-BDC)₂₄(DMF)₂₀(H₂O)₄]•24DMF•40H₂O (MOP@Ei2-1), where m-BDC is the 1,3-benzenedicarboxylic ligand and DMF is N,N′-dimethylformamide. The structure of MOP@Ei2-1 consists of Cu24 clusters arranged in such a way that 12 paddle-wheels are connected through m-BDC ligands. The clusters exhibit an internal cavity where crystallization molecules of DMF and water are located. Adsorption of dyes and iodine as pollutant examples has been carried out, focusing attention on the kinetics of the rapid process.

Keywords: adsorption, organic dyes, iodine, metal organic frameworks

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2438 Clay Hydrogel Nanocomposite for Controlled Small Molecule Release

Authors: Xiaolin Li, Terence Turney, John Forsythe, Bryce Feltis, Paul Wright, Vinh Truong, Will Gates

Abstract:

Clay-hydrogel nanocomposites have attracted great attention recently, mainly because of their enhanced mechanical properties and ease of fabrication. Moreover, the unique platelet structure of clay nanoparticles enables the incorporation of bioactive molecules, such as proteins or drugs, through ion exchange, adsorption or intercalation. This study seeks to improve the mechanical and rheological properties of a novel hydrogel system, copolymerized from a tetrapodal polyethylene glycol (PEG) thiol and a linear, triblock PEG-PPG-PEG (PPG: polypropylene glycol) α,ω-bispropynoate polymer, with the simultaneous incorporation of various amounts of Na-saturated, montmorillonite clay (MMT) platelets (av. lateral dimension = 200 nm), to form a bioactive three-dimensional network. Although the parent hydrogel has controlled swelling ability and its PEG groups have good affinity for the clay platelets, it suffers from poor mechanical stability and is currently unsuitable for potential applications. Nanocomposite hydrogels containing 4wt% MMT showed a twelve-fold enhancement in compressive strength, reaching 0.75MPa, and also a three-fold acceleration in gelation time, when compared with the parent hydrogel. Interestingly, clay nanoplatelet incorporation into the hydrogel slowed down the rate of its dehydration in air. Preliminary results showed that protein binding by the MMT varied with the nature of the protein, as horseradish peroxidase (HRP) was more strongly bound than bovine serum albumin. The HRP was no longer active when bound, presumably as a result of extensive structural refolding. Further work is being undertaken to assess protein binding behaviour within the nanocomposite hydrogel for potential diabetic wound healing applications.

Keywords: hydrogel, nanocomposite, small molecule, wound healing

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2437 Graph Neural Network-Based Classification for Disease Prediction in Health Care Heterogeneous Data Structures of Electronic Health Record

Authors: Raghavi C. Janaswamy

Abstract:

In the healthcare sector, heterogenous data elements such as patients, diagnosis, symptoms, conditions, observation text from physician notes, and prescriptions form the essentials of the Electronic Health Record (EHR). The data in the form of clear text and images are stored or processed in a relational format in most systems. However, the intrinsic structure restrictions and complex joins of relational databases limit the widespread utility. In this regard, the design and development of realistic mapping and deep connections as real-time objects offer unparallel advantages. Herein, a graph neural network-based classification of EHR data has been developed. The patient conditions have been predicted as a node classification task using a graph-based open source EHR data, Synthea Database, stored in Tigergraph. The Synthea DB dataset is leveraged due to its closer representation of the real-time data and being voluminous. The graph model is built from the EHR heterogeneous data using python modules, namely, pyTigerGraph to get nodes and edges from the Tigergraph database, PyTorch to tensorize the nodes and edges, PyTorch-Geometric (PyG) to train the Graph Neural Network (GNN) and adopt the self-supervised learning techniques with the AutoEncoders to generate the node embeddings and eventually perform the node classifications using the node embeddings. The model predicts patient conditions ranging from common to rare situations. The outcome is deemed to open up opportunities for data querying toward better predictions and accuracy.

Keywords: electronic health record, graph neural network, heterogeneous data, prediction

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2436 The Role of Semi Open Spaces on Exploitation of Wind-Driven Ventilation

Authors: Paria Saadatjoo

Abstract:

Given that HVAC systems are the main sources of carbon dioxide producers, developing ways to reduce dependence on these systems and making use of natural resources is too important to achieve environmentally friendly buildings. A major part of building potential in terms of using natural energy resources depends on its physical features. So architectural decisions at the first step of the design process can influence the building's energy efficiency significantly. Implementation of semi-open spaces into solid apartment blocks inspired by the concept of courtyard in ancient buildings as a passive cooling strategy is currently enjoying great popularity. However, the analysis of these features and their effect on wind behavior at initial design steps is a difficult task for architects. The main objective of this research was to investigate the influence of semi-open to closed space ratio on airflow patterns in and around midrise buildings and introduce the best ratio in terms of harnessing natural ventilation. The main strategy of this paper was semi-experimental, and the research methodology was descriptive statistics. At the first step, by changing the terrace area, 6 models with various open to closed space ratios were created. These forms were then transferred to CFD software to calculate the primary indicators of natural ventilation potentials such as wind force coefficient, air flow rate, age of air distribution, etc. Investigations indicated that modifying the terrace area and, in other words, the open to closed space ratio influenced the wind force coefficient, airflow rate, and age of air distribution.

Keywords: natural ventilation, wind, midrise, open space, energy

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2435 Review of Numerical Models for Granular Beds in Solar Rotary Kilns for Thermal Applications

Authors: Edgar Willy Rimarachin Valderrama, Eduardo Rojas Parra

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Thermal energy from solar radiation is widely present in power plants, food drying, chemical reactors, heating and cooling systems, water treatment processes, hydrogen production, and others. In the case of power plants, one of the technologies available to transform solar energy into thermal energy is by solar rotary kilns where a bed of granular matter is heated through concentrated radiation obtained from an arrangement of heliostats. Numerical modeling is a useful approach to study the behavior of granular beds in solar rotary kilns. This technique, once validated with small-scale experiments, can be used to simulate large-scale processes for industrial applications. This study gives a comprehensive classification of numerical models used to simulate the movement and heat transfer for beds of granular media within solar rotary furnaces. In general, there exist three categories of models: 1) continuum, 2) discrete, and 3) multiphysics modeling. The continuum modeling considers zero-dimensional, one-dimensional and fluid-like models. On the other hand, the discrete element models compute the movement of each particle of the bed individually. In this kind of modeling, the heat transfer acts during contacts, which can occur by solid-solid and solid-gas-solid conduction. Finally, the multiphysics approach considers discrete elements to simulate grains and a continuous modeling to simulate the fluid around particles. This classification allows to compare the advantages and disadvantages for each kind of model in terms of accuracy, computational cost and implementation.

Keywords: granular beds, numerical models, rotary kilns, solar thermal applications

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2434 Investigation on Reducing the Bandgap in Nanocomposite Polymers by Doping

Authors: Sharvare Palwai, Padmaja Guggilla

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Smart materials, also called as responsive materials, undergo reversible physical or chemical changes in their properties as a consequence of small environmental variations. They can respond to a single or multiple stimuli such as stress, temperature, moist, electric or magnetic fields, light, or chemical compounds. Hence smart materials are the basis of many applications, including biosensors and transducers, particularly electroactive polymers. As the polymers exhibit good flexibility, high transparency, easy processing, and low cost, they would be promising for the sensor material. Polyvinylidene Fluoride (PVDF), being a ferroelectric polymer, exhibits piezoelectric and pyro electric properties. Pyroelectric materials convert heat directly into electricity, while piezoelectric materials convert mechanical energy into electricity. These characteristics of PVDF make it useful in biosensor devices and batteries. However, the influence of nanoparticle fillers such as Lithium Tantalate (LiTaO₃/LT), Potassium Niobate (KNbO₃/PN), and Zinc Titanate (ZnTiO₃/ZT) in polymer films will be studied comprehensively. Developing advanced and cost-effective biosensors is pivotal to foresee the fullest potential of polymer based wireless sensor networks, which will further enable new types of self-powered applications. Finally, nanocomposites films with best set of properties; the sensory elements will be designed and tested for their performance as electric generators under laboratory conditions. By characterizing the materials for their optical properties and investigate the effects of doping on the bandgap energies, the science in the next-generation biosensor technologies can be advanced.

Keywords: polyvinylidene fluoride, PVDF, lithium tantalate, potassium niobate, zinc titanate

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2433 Electrochemistry and Performance of Bryophylum pinnatum Leaf (BPL) Electrochemical Cell

Authors: M. A. Mamun, M. I. Khan, M. H. Sarker, K. A. Khan, M. Shajahan

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The study was carried out to investigate on an innovative invention, Pathor Kuchi Leaf (PKL) cell, which is fueled with PKL sap of widely available plant called Bryophyllum pinnatum as an energy source for use in PKL battery to generate electricity. This battery, a primary source of electricity, has several order of magnitude longer shelf-lives than the traditional Galvanic cell battery, is still under investigation. In this regard, we have conducted some experiments using various instruments including Atomic Absorption Spectrophotometer (AAS), Ultra-Violet Visible spectrophotometer (UV-Vis), pH meter, Ampere-Volt-Ohm Meter (AVO Meter), etc. The AAS, UV-Vis, and pH-metric analysis data provided that the potential and current were produced as the Zn electrode itself acts as reductant while Cu2+ and H+ ions are behaving as the oxidant. The significant influence of secondary salt on current and potential leads to the dissociation of weak organic acids in PKL juice, and subsequent enrichment to the reactant ions by the secondary salt effects. However, the liquid junction potential was not as great as minimized with the opposite transference of organic acid anions and H+ ions as their dissimilar ionic mobilities. Moreover, the large value of the equilibrium constant (K) implies the big change in Gibbs free energy (∆G), the more electromotive force works in electron transfer during the forward electrochemical reaction which coincides with the fast reduction of the weight of zinc plate, revealed the additional electrical work in the presence of PKL sap. This easily fabricated high-performance PKL battery can show an excellent promise during the off-peak across the countryside.

Keywords: Atomic Absorption Spectrophotometer (AAS), Bryophylum Pinnatum Leaf (BPL), electricity, electrochemistry, organic acids

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2432 Social and Digital Transformation of the Saudi Education System: A Cyberconflict Analysis

Authors: Mai Alshareef

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The Saudi government considers the modernisation of the education system as a critical component of the national development plan, Saudi Vision 2030; however, this sudden reform creates tension amongst Saudis. This study examines first the reflection of the social and digital education reform on stakeholders and the general Saudi public, and second, the influence of information and communication technologies (ICTs) on the ethnoreligious conflict in Saudi Arabia. This study employs Cyberconflict theory to examine conflicts in the real world and cyberspace. The findings are based on a qualitative case study methodology that uses netnography, an analysis of 3,750 Twitter posts and semi-structural interviews with 30 individuals, including key actors in the Saudi education sector and Twitter activists during 2019\2020. The methods utilised are guided by thematic analysis to map an understanding of factors that influence societal conflicts in Saudi Arabia, which in this case include religious, national, and gender identity. Elements of Cyberconflict theory are used to better understand how conflicting groups build their identities in connection to their ethnic/religious/cultural differences and competing national identities. The findings correspond to the ethnoreligious components of the Cyberconflict theory. Twitter became a battleground for liberals, conservatives, the Saudi public and elites, and it is used in a novel way to influence public opinion and to challenge the media monopoly. Opposing groups relied heavily on a discourse of exclusion and inclusion and showed ethnic and religious affiliations, national identity, and chauvinism. The findings add to existing knowledge in the cyberconflict field of study, and they also reveal outcomes that are critical to the Saudi Arabian national context.

Keywords: education, cyberconflict, Twitter, national identity

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2431 Relevance of Reliability Approaches to Predict Mould Growth in Biobased Building Materials

Authors: Lucile Soudani, Hervé Illy, Rémi Bouchié

Abstract:

Mould growth in living environments has been widely reported for decades all throughout the world. A higher level of moisture in housings can lead to building degradation, chemical component emissions from construction materials as well as enhancing mould growth within the envelope elements or on the internal surfaces. Moreover, a significant number of studies have highlighted the link between mould presence and the prevalence of respiratory diseases. In recent years, the proportion of biobased materials used in construction has been increasing, as seen as an effective lever to reduce the environmental impact of the building sector. Besides, bio-based materials are also hygroscopic materials: when in contact with the wet air of a surrounding environment, their porous structures enable a better capture of water molecules, thus providing a more suitable background for mould growth. Many studies have been conducted to develop reliable models to be able to predict mould appearance, growth, and decay over many building materials and external exposures. Some of them require information about temperature and/or relative humidity, exposure times, material sensitivities, etc. Nevertheless, several studies have highlighted a large disparity between predictions and actual mould growth in experimental settings as well as in occupied buildings. The difficulty of considering the influence of all parameters appears to be the most challenging issue. As many complex phenomena take place simultaneously, a preliminary study has been carried out to evaluate the feasibility to sadopt a reliability approach rather than a deterministic approach. Both epistemic and random uncertainties were identified specifically for the prediction of mould appearance and growth. Several studies published in the literature were selected and analysed, from the agri-food or automotive sectors, as the deployed methodology appeared promising.

Keywords: bio-based materials, mould growth, numerical prediction, reliability approach

Procedia PDF Downloads 46
2430 Effect of Distance Education Students Motivation with the Turkish Language and Literature Course

Authors: Meva Apaydin, Fatih Apaydin

Abstract:

Role of education in the development of society is great. Teaching and training started with the beginning of the history and different methods and techniques which have been applied as the time passed and changed everything with the aim of raising the level of learning. In addition to the traditional teaching methods, technology has been used in recent years. With the beginning of the use of internet in education, some problems which could not be soluted till that time has been dealt and it is inferred that it is possible to educate the learners by using contemporary methods as well as traditional methods. As an advantage of technological developments, distance education is a system which paves the way for the students to be educated individually wherever and whenever they like without the needs of physical school environment. Distance education has become prevalent because of the physical inadequacies in education institutions, as a result; disadvantageous circumstances such as social complexities, individual differences and especially geographical distance disappear. What’s more, the high-speed of the feedbacks between teachers and learners, improvement in student motivation because there is no limitation of time, low-cost, the objective measuring and evaluation are on foreground. In spite of the fact that there is teaching beneficences in distance education, there are also limitations. Some of the most important problems are that : Some problems which are highly possible to come across may not be solved in time, lack of eye-contact between the teacher and the learner, so trust-worthy feedback cannot be got or the problems stemming from the inadequate technological background are merely some of them. Courses are conducted via distance education in many departments of the universities in our country. In recent years, giving lectures such as Turkish Language, English, and History in the first grades of the academic departments in the universities is an application which is constantly becoming prevalent. In this study, the application of Turkish Language course via distance education system by analyzing advantages and disadvantages of the distance education system which is based on internet.

Keywords: distance education, Turkish language, motivation, benefits

Procedia PDF Downloads 436
2429 Reflecting and Teaching on the Dialectical Nature of Social Work

Authors: Eli Buchbinder

Abstract:

Dialectics theory perceives two or more forces or themes as mutually opposed and negating on the one hand and as interdependent for their definition, existence, and resolution on the other. Such opposites might never be fully reconciled but might, simultaneously, continue to produce a higher level of integration and synthesis as well as tension, contradictions, and paradoxes. The identity of social work is constructed by poles; an understanding that emerges through key concepts that shape the profession. The key concept of person-in-environment creates dialectical tensions between the psychological versus the social pole. Important examples that reflect this focus on the psychological versus the social nature of human beings. This meta-perspective influences and constructs the implementation of values, ways of intervention, and professional relationships, e.g., creating a conflict between personal/social empowerment and social control and correction as the aims of the profession. Social work is dynamic and changing, with a unique way of perceiving and conceptualizing human behavior. Social workers must be able to face and accept the contradicting elements inherent in practicing social work. The basic philosophy for social work education is a dialectic conceptualization. In light of the above, social work students require dialectics as a critical mode of perception, reflection, and intervention. In the presentation, the focus will be on reflection on teaching students to conceptualize dialectics as a frame when training to be social workers. It is believed that the focus should emphasis two points: 1) the need to assist students to identify poles and to analyze the interrelationships created between them while coping emotionally with the tension and difficulties involved in containing these poles; 2) teaching students to integrate poles as a basis for assessment, planning, and intervention.

Keywords: professional ontology, a generic social work education, skills and values of social work, reflecting on social work teaching methods

Procedia PDF Downloads 85
2428 Metrology in Egyptian Architecture, Interrelation with Archaeology

Authors: Monica M. Marcos

Abstract:

In the framework of Archaeological Research, Heritage Conservation and Restoration, the object of study is metrology applied in composition of religious architecture in ancient Egypt, and usefulness in Archaology. The objective is the determination of the geometric and metrological relations in architectural models and the module used in the initial project of the buildings. The study and data collection of religious buildings, tombs and temples of the ancient Egypt, is completed with plans. The measurements systematization and buildings modulation makes possible to establish common compositional parameters, with a module determined by the measurement unit used. The measurement system corresponding to the main period of egyptian history, was the Egyptian royal cubit. The analysis of units measurements, used in architectural design, provides exact numbers on buildable spaces dimensions. It allows establishing proportional relationships between them, and finding a geometric composition module, on which the original project was based. This responds to a philosophical and functional concept of projected spaces. In the heritage rehabilitation and restoration field, knowledge of metrology helps in excavation, reconstruction and restoration of construction elements. The correct use of metrology contributes to the identification of possible work areas, helping to locate where the damaged or missing areas are. Also in restoration projects, metrology is useful for reordering and locating decontextualized parts of buildings. The conversion of measurements taken in the current International System to the ancient egyptian measurements, allows understand its conceptual purpose and its functionality, which makes easier to carry out archaeological intervention. In the work carried out in archaeological excavations, metrology is an essential tool for locating sites and establishing work zones.

Keywords: egyptology, metrology, archaeology, measurements, Egyptian cubit

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2427 Producing of Amorphous-Nanocrystalline Composite Powders

Authors: K. Tomolya, D. Janovszky, A. Sycheva, M. Sveda, A. Roosz

Abstract:

CuZrAl amorphous alloys have attracted high interest due to unique physical and mechanical properties, which can be enhanced by adding of Ni and Ti elements. It is known that this properties can be enhanced by crystallization of amorphous alloys creating nanocrystallines in the matrix. The present work intends to produce nanosized crystalline parti-cle reinforced amorphous matrix composite powders by crystallization of amorphous powders. As the first step the amorphous powders were synthe-tized by ball-milling of crystalline powders. (Cu49Zr45Al6) 80Ni10Ti10 and (Cu49Zr44Al7) 80Ni10Ti10 (at%) alloys were ball-milled for 12 hours in order to reach the fully amorphous structure. The impact en-ergy of the balls during milling causes the change of the structure in the powders. Scanning electron microscopical (SEM) images shows that the phases mixed first and then changed into a fully amorphous matrix. Furthermore, nanosized particles in the amorphous matrix were crystallized by heat treatment of the amorphous powders that was confirmed by TEM measurement. It was of importance to define the tem-perature when the amorphous phase starts to crystal-lize. Amorphous alloys have a special heating curve and characteristic temperatures, which can be meas-ured by differential scanning calorimetry (DSC). A typical DSC curve of an amorphous alloy exhibits an endothermic event characteristic of the equilibrium glass transition (Tg) and a distinct undercooled liquid region, followed by one or two exothermic events corresponding to crystallization processes (Tp). After measuring the DSC traces of the amorphous powders, the annealing temperatures should be determined between Tx and Tp. In our experiments several temperatures from the annealing temperature range were selected and de-pendency of crystallized nanoparticles fraction on their hardness was investigated.

Keywords: amorphous structure, composite, mechanical milling, powder, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), transmission electronmocroscopy (TEM)

Procedia PDF Downloads 450
2426 In a Situation of Great Distress: Cross Border Migration and the Quest for Enduring Security in North-East Nigeria

Authors: Nuhu Bitrus Mailabari

Abstract:

Nigeria is a highly multifarious nation trapped between affluence and affliction. On one hand, the state has vast territorial size, economic strength, relative internal cohesion, and good external linkages. On the other, it is bedeviled with enormous challenges. It is common knowledge that the North-East geo-political zone has suffered colossal destruction for the most part of the last ten years due to the activities of the insurgent group Boko Haram. Several factors (political, economic, religious, socio-cultural) have been credited with the heightened insecurity in the region. Without a doubt, the security crisis in the region has rekindled several discussions critical to Nigeria’s security architecture. However, the debate on finding an enduring solution to the devastation in the North East continually neglects the nexus between cross border migration and national security. Using content analysis, this paper debates two main issues that continue to affect security in the North East. One, the cumulative impact of the Economic Community of West African States (ECOWAS) protocol on the free movement of people and goods. Two, the porous nature of Nigeria’s borders. Theoretically, the paper will rely on the systems theory because of its broad focus on structure, linkage, and process. The work concludes in twofold. First, that cross border migration and poor border management processes further worsened the political and socio-economic conditions of a region that is already in a bad state. Secondly, in addition to the existing strategies, Nigeria must develop a holistic approach including new methods of handling cross border movements in solving the security issues.

Keywords: border, cross border, migration, Nigeria, northeast region, security

Procedia PDF Downloads 164
2425 Harnessing Earth's Electric Field and Transmission of Electricity

Authors: Vaishakh Medikeri

Abstract:

Energy in this Universe is the most basic characteristic of every particle. Since the birth of life on this planet, there has been a quest undertaken by the living beings to analyze, understand and harness the precious natural facts of the nature. In this quest, one of the greatest undertaken is the process of harnessing the naturally available energy. Scientists around the globe have discovered many ways to harness the freely available energy. But even today we speak of “Power Crisis”. Nikola Tesla once said “Nature has stored up in this universe infinite energy”. Energy is everywhere around us in unlimited quantities; all of it waiting to be harnessed by us. Here in this paper a method has been proposed to harness earth's electric field and transmit the stored electric energy using strong magnetic fields and electric fields. In this paper a new technique has been proposed to harness earth's electric field which is everywhere around the world in infinite quantities. Near the surface of the earth there is an electric field of about 120V/m. This electric field is used to charge a capacitor with high capacitance. Later the energy stored is allowed to pass through a device which converts the DC stored into AC. The AC so produced is then passed through a step down transformer to magnify the incoming current. Later the current passes through the RLC circuit. Later the current can be transmitted wirelessly using the principle of resonant inductive coupling. The proposed apparatus can be placed in most of the required places and any circuit tuned to the frequency of the transmitted current can receive the energy. The new source of renewable energy is of great importance if implemented since the apparatus is not costly and can be situated in most of the required places. And also the receiver which receives the transmitted energy is just an RLC circuit tuned to the resonant frequency of the transmitted energy. By using the proposed apparatus the energy losses can be reduced to a very large extent.

Keywords: capacitor, inductive resonant coupling, RLC circuit, transmission of electricity

Procedia PDF Downloads 373
2424 The Development of Student Core Competencies through the STEM Education Opportunities in Classroom

Authors: Z. Dedovets, M. Rodionov

Abstract:

The goal of the modern education system is to prepare students to be able to adapt to ever-changing life situations. They must be able to acquire required knowledge independently; apply such knowledge in practice to solve various problems by using modern technologies; think critically and creatively; competently use information; be communicative, work in a team; and develop their own moral values, intellect and cultural awareness. As a result, the status of education significantly increases; new requirements to its quality have been formed. In recent years, the competency-based approach in education has become of significant interest. This approach is a strengthening of applied and practical characteristics of a school education and leads to the forming of the key students’ competencies which define their success in future life. In this article, the authors’ attention focuses on a range of key competencies, educational, informational and communicative and on the possibility to develop such competencies via STEM education. This research shows the change in students’ attitude towards scientific disciplines such as mathematics, general science, technology and engineering as a result of STEM education. Two-staged analyzes questionnaires completed by students of forms II to IV in the republic of Trinidad and Tobago allowed the authors to categorize students between two levels that represent students’ attitude to various disciplines. The significance of differences between selected levels was confirmed with the use of Pearsons’ chi-squared test. In summary, the analysis of obtained data makes it possible to conclude that STEM education has a great potential for development of core students’ competencies and encourages the development of positive student attitude towards the above mentioned above scientific disciplines.

Keywords: STEM, science, technology, engineering, mathematics, students’ competency, Pearson's chi-squared test

Procedia PDF Downloads 387
2423 Metaphors Underlying Idiomatic Expressions in Trilingual Perspective: Contributions to the Teaching of Lexicon and to Materials Development

Authors: Marilei Amadeu Sabino

Abstract:

Idiomatic expressions are linguistic phraseologisms present in natural languages. Known to be metaphorical linguistic combinations, a good majority of them provide elements that reveal important cultural aspects of their linguistic community through their metaphors. With the advent of Cognitive Linguistics (more specifically of Cognitive Semantics), the metaphor ceased to be related to poetic language and rhetorical embellishment and came to be seen as part of simple everyday language, reflecting the way human beings think, act and conceive reality, i. e., a fundamental mechanism of human conceptualizations of the world. In this sense, it came to be conceived as an inevitable mechanism for representing the nature of thought and language. The speakers, in conceptualizing reality, often use metaphorically parts of the body in expressions known as somatic. Several conceptual metaphors appear to be potentially universal or near-universal, because people across the world share certain bodily experiences. In these terms, many linguistic metaphors may be identical or very similar in several languages. These similarities, according to the Theory of Conceptual Metaphor, derive from universal aspects of the human body. Thus, this research aims to investigate the nature of some metaphors underlying somatic idiomatic expressions of Portuguese, Italian and English languages, establishing a pattern of similarities and differences among them from a trilingual perspective. The analysis shows that much of the studied expressions are really structurally, semantically and metaphorically identical or similar in the three languages. These findings incite relevant discussions concerning mother and foreign language learning and aim to contribute to the teaching of phraseological Lexicon as well as to materials development in mono and multilingual perspectives.

Keywords: idiomatic expressions, materials development, metaphors, phraseological lexicon, teaching and learning

Procedia PDF Downloads 192
2422 A Review of the Handling and Disposal of Botulinum Toxin in a Maxillofacial Unit

Authors: Ashana Gupta

Abstract:

Aim: In the UK, Botulinum Toxin (botox) is authorised for treating chronic myofascial pain secondary to masseter muscle hypertrophy (Fedorowicz et al. 2013). This audit aimed to ensure the Maxillofacial Unit is meeting the trust guidelines for the safe storage and disposal of botox. Method: The trust upholds a strict policy for botox handling. The audit was designed to optimise several elements including Staff awareness of regulations around botox handling A questionnaire was designed to test knowledge of advised storage temperatures, reporting of adverse events, disposal procedures and regulatory authorities. Steps taken to safely delivertoxin and eliminate unused toxin. A checklist was completed. These include marks for storagetemperature, identification checks, disposal of sharps, deactivation of toxin, and disposal. Results: All staff correctly stated storage requirements for toxin. 75% staff (n=8) were unsure about reporting and regulations. Whilst all staff knew how to dispose of vials, 0% staff showed awareness for the crucial step of deactivating toxin. All checklists (n=20) scored 100% for adequate storage, ID checks, and toxin disposal. However, there were no steps taken to deactivate toxin in any cases. Staff training took place with revision to clinical protocols. In line with Trust guidelines, an additional clinical step has been introduced including use of 0.5% sodium hypochlorite to deactivate botox. Conclusion: Deactivation is crucial to ensure residual toxin is not misused. There are cases of stolen botox within South-Tees Hospital (Woodcock, 2014). This audit was successful in increasing compliance to safe handling and disposal of botox by 100% and ensured our hospitalmeets Trust guidance.

Keywords: botulinum toxin, aesthetics, handling, disposal

Procedia PDF Downloads 209
2421 Crab Shell Waste Chitosan-Based Thin Film for Acoustic Sensor Applications

Authors: Maydariana Ayuningtyas, Bambang Riyanto, Akhiruddin Maddu

Abstract:

Industrial waste of crustacean shells, such as shrimp and crab, has been considered as one of the major issues contributing to environmental pollution. The waste processing mechanisms to form new, practical substances with added value have been developed. Chitosan, a derived matter from chitin, which is obtained from crab and shrimp shells, performs prodigiously in broad range applications. A chitosan composite-based diaphragm is a new inspiration in fiber optic acoustic sensor advancement. Elastic modulus, dynamic response, and sensitivity to acoustic wave of chitosan-based composite film contribute great potentials of organic-based sound-detecting material. The objective of this research was to develop chitosan diaphragm application in fiber optic microphone system. The formulation was conducted by blending 5% polyvinyl alcohol (PVA) solution with dissolved chitosan at 0%, 1% and 2% in 1:1 ratio, respectively. Composite diaphragms were characterized for the morphological and mechanical properties to predict the desired acoustic sensor sensitivity. The composite with 2% chitosan indicated optimum performance with 242.55 µm thickness, 67.9% relative humidity, and 29-76% light transmittance. The Young’s modulus of 2%-chitosan composite material was 4.89×104 N/m2, which generated the voltage amplitude of 0.013V and performed sensitivity of 3.28 mV/Pa at 1 kHz. Based on the results above, chitosan from crustacean shell waste can be considered as a viable alternative material for fiber optic acoustic sensor sensing pad development. Further, the research in chitosan utilisation is proposed as novel optical microphone development in anthropogenic noise controlling effort for environmental and biodiversity conservation.

Keywords: acoustic sensor, chitosan, composite, crab shell, diaphragm, waste utilisation

Procedia PDF Downloads 257