Search results for: variable range of small polaron hopping
Commenced in January 2007
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Edition: International
Paper Count: 12704

Search results for: variable range of small polaron hopping

8444 Improvement of the Traditional Techniques of Artistic Casting through the Development of Open Source 3D Printing Technologies Based on Digital Ultraviolet Light Processing

Authors: Drago Diaz Aleman, Jose Luis Saorin Perez, Cecile Meier, Itahisa Perez Conesa, Jorge De La Torre Cantero

Abstract:

Traditional manufacturing techniques used in artistic contexts compete with highly productive and efficient industrial procedures. The craft techniques and associated business models tend to disappear under the pressure of the appearance of mass-produced products that compete in all niche markets, including those traditionally reserved for the work of art. The surplus value derived from the prestige of the author, the exclusivity of the product or the mastery of the artist, do not seem to be sufficient reasons to preserve this productive model. In the last years, the adoption of open source digital manufacturing technologies in small art workshops can favor their permanence by assuming great advantages such as easy accessibility, low cost, and free modification, adapting to specific needs of each workshop. It is possible to use pieces modeled by computer and made with FDM (Fused Deposition Modeling) 3D printers that use PLA (polylactic acid) in the procedures of artistic casting. Models printed by PLA are limited to approximate minimum sizes of 3 cm, and optimal layer height resolution is 0.1 mm. Due to these limitations, it is not the most suitable technology for artistic casting processes of smaller pieces. An alternative to solve size limitation, are printers from the type (SLS) "selective sintering by laser". And other possibility is a laser hardens, by layers, metal powder and called DMLS (Direct Metal Laser Sintering). However, due to its high cost, it is a technology that is difficult to introduce in small artistic foundries. The low-cost DLP (Digital Light Processing) type printers can offer high resolutions for a reasonable cost (around 0.02 mm on the Z axis and 0.04 mm on the X and Y axes), and can print models with castable resins that allow the subsequent direct artistic casting in precious metals or their adaptation to processes such as electroforming. In this work, the design of a DLP 3D printer is detailed, using backlit LCD screens with ultraviolet light. Its development is totally "open source" and is proposed as a kit made up of electronic components, based on Arduino and easy to access mechanical components in the market. The CAD files of its components can be manufactured in low-cost FDM 3D printers. The result is less than 500 Euros, high resolution and open-design with free access that allows not only its manufacture but also its improvement. In future works, we intend to carry out different comparative analyzes, which allow us to accurately estimate the print quality, as well as the real cost of the artistic works made with it.

Keywords: traditional artistic techniques, DLP 3D printer, artistic casting, electroforming

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8443 The Diversity of Contexts within Which Adolescents Engage with Digital Media: Contributing to More Challenging Tasks for Parents and a Need for Third Party Mediation

Authors: Ifeanyi Adigwe, Thomas Van der Walt

Abstract:

Digital media has been integrated into the social and entertainment life of young children, and as such, the impact of digital media appears to affect young people of all ages and it is believed that this will continue to shape the world of young children. Since, technological advancement of digital media presents adolescents with diverse contexts, platforms and avenues to engage with digital media outside the home environment and from parents' supervision, a wide range of new challenges has further complicated the already difficult tasks for parents and altered the landscape of parenting. Despite the fact that adolescents now have access to a wide range of digital media technologies both at home and in the learning environment, parenting practices such as active, restrictive, co-use, participatory and technical mediations are important in mitigating of online risks adolescents may encounter as a result of digital media use. However, these mediation practices only focus on the home environment including digital media present in the home and may not necessarily transcend outside the home and other learning environments where adolescents use digital media for school work and other activities. This poses the question of who mediates adolescent's digital media use outside the home environment. The learning environment could be a ''loose platform'' where an adolescent can maximise digital media use considering the fact that there is no restriction in terms of content and time allotted to using digital media during school hours. That is to say that an adolescent can play the ''bad boy'' online in school because there is little or no restriction of digital media use and be exposed to online risks and play the ''good boy'' at home because of ''heavy'' parental mediation. This is the reason why parent mediation practices have been ineffective because a parent may not be able to track adolescents digital media use considering the diversity of contexts, platforms and avenues adolescents use digital media. This study argues that due to the diverse nature of digital media technology, parents may not be able to monitor the 'whereabouts' of their children in the digital space. This is because adolescent digital media usage may not only be confined to the home environment but other learning environments like schools. This calls for urgent attention on the part of teachers to understand the intricacies of how digital media continue to shape the world in which young children are developing and learning. It is, therefore, imperative for parents to liaise with the schools of their children to mediate digital media use during school hours. The implication of parents- teachers mediation practices are discussed. The article concludes by suggesting that third party mediation by teachers in schools and other learning environments should be encouraged and future research needs to consider the emergent strategy of teacher-children mediation approach and the implication for policy for both the home and learning environments.

Keywords: digital media, digital age, parent mediation, third party mediation

Procedia PDF Downloads 154
8442 Factors Affecting eHealth Literacy among Nursing Students in Jordan

Authors: Laila Habiballah, Ahmad Tubaishat

Abstract:

Background: with the development of information and communication technology, using the internet as a source to obtain health information is increasing. Nursing students as future health care providers should have the skills of locating, evaluating and using online health information. This will enable them to help their patients and families to make informed decisions. Aim: this study has a two-fold aim. The first is to assess the eHealth literacy among nursing students in Jordan. The second aim is to explore the factors that have an effect on the eHealth literacy. Methods: this is a descriptive cross-sectional survey that conducted in two universities in Jordan; public and private one. A number of 541 students from both universities were completed the eHEALS scale, which is an instrument designed to measure the eHealth literacy. Some additional personal and demographical variable were collected to explore its effect on eHealth literacy. Results: Students have a high perceived level of e-Health literacy (M=3.62, SD=0.58). They are aware of the available online health resources, know how to search, locate, and use these resources. But, they do not have the skills to evaluate these resources and cannot differentiate between the high and low-quality resources. The results showed as well that type of university, type of students' admission, academic level, students' skills of using the internet, and the perception of usefulness and importance of internet have an effect on the eHealth literacy. While the age, gender, GPA, and the frequency of using the internet was no significant factors. Conclusion: This study represents a baseline reference for the eHealth literacy in Jordan. Students have some skills of eHealth literacy and other skills need to be improved. Nursing educators and administrators should integrate and incorporate the skills of eHealth literacy in the curriculum.

Keywords: eHealth, literacy, nursing, students, Jordan

Procedia PDF Downloads 388
8441 Diversity and Use of Agroforestry Yards of Family Farmers of Ponte Alta – Gama, Federal District, Brazil

Authors: Kever Bruno Paradelo Gomes, Rosana Carvalho Martins

Abstract:

The home gardens areas are production systems, which are located near the homes and are quite common in the tropics. They consist of agricultural and forest species and may also involve the raising of small animals to produce food for subsistence as well as income generation, with a special focus on the conservation of biodiversity. Home gardens are diverse Agroforestry systems with multiple uses, among many, food security, income aid, traditional medicine. The work was carried out on rural properties of the family farmers of the Ponte Alta Rural Nucleus, Gama Administrative Region, in the city of Brasília, Federal District- Brazil. The present research is characterized methodologically as a quantitative, exploratory and descriptive nature. The instruments used in this research were: bibliographic survey and semi-structured questionnaire. The data collection was performed through the application of a semi-structured questionnaire, containing questions that referred to the perception and behavior of the interviewed producer on the subject under analysis. In each question, the respondent explained his knowledge about sustainability, agroecological practices, environmental legislation, conservation methods, forest and medicinal species, ago social and socioeconomic characteristics, use and purpose of agroforestry and technical assistance. The sample represented 55.62% of the universe of the study. We interviewed 99 people aged 18-83 years, with a mean age of 49 years. The low level of education, coupled with the lack of training and guidance for small family farmers in the Ponte Alta Rural Nucleus, is one of the limitations to the development of practices oriented towards sustainable and agroecological agriculture in the nucleus. It is observed that 50.5% of the interviewed people landed with agroforestry yards less than 20 years ago, and only 16.17% of them are older than 35 years. In identifying agriculture as the main activity of most of the rural properties studied, attention is drawn to the cultivation of medicinal plants, fruits and crops as the most extracted products. However, it is verified that the crops in the backyards have the exclusive purpose of family consumption, which could be complemented with the marketing of the surplus, as well as with the aggregation of value to the cultivated products. Initiatives such as this may contribute to the increase in family income and to the motivation and value of the crop in agroecological gardens. We conclude that home gardens of Ponte Alta are highly diverse thus contributing to local biodiversity conservation of are managed by women to ensure food security and allows income generation. The tradition of existing knowledge on the use and management of the diversity of resources used in agroforestry yards is of paramount importance for the development of sustainable alternative practices.

Keywords: agriculture, agroforestry system, rural development, sustainability

Procedia PDF Downloads 140
8440 An AK-Chart for the Non-Normal Data

Authors: Chia-Hau Liu, Tai-Yue Wang

Abstract:

Traditional multivariate control charts assume that measurement from manufacturing processes follows a multivariate normal distribution. However, this assumption may not hold or may be difficult to verify because not all the measurement from manufacturing processes are normal distributed in practice. This study develops a new multivariate control chart for monitoring the processes with non-normal data. We propose a mechanism based on integrating the one-class classification method and the adaptive technique. The adaptive technique is used to improve the sensitivity to small shift on one-class classification in statistical process control. In addition, this design provides an easy way to allocate the value of type I error so it is easier to be implemented. Finally, the simulation study and the real data from industry are used to demonstrate the effectiveness of the propose control charts.

Keywords: multivariate control chart, statistical process control, one-class classification method, non-normal data

Procedia PDF Downloads 420
8439 Graphene-Based Reconfigurable Lens Antenna for 5G/6G and Satellite Networks

Authors: André Lages, Victor Dmitriev, Juliano Bazzo, Gianni Portela

Abstract:

This work evaluates the feasibility of the graphene application to perform as a wideband reconfigurable material for lens antennas in 5G/6G and satellite applications. Based on transformation optics principles, the electromagnetic waves can be efficiently guided by modifying the effective refractive index. Graphene behavior can range between a lossy dielectric and a good conductor due to the variation of its chemical potential bias, thus arising as a promising solution for electromagnetic devices. The graphene properties and a lens antenna comprising multiples layers and periodic arrangements of graphene patches were analyzed using full-wave simulations. A dipole directivity was improved from 7 to 18.5 dBi at 29 GHz. In addition, the realized gain was enhanced 7 dB across a 14 GHz bandwidth within the Ka/5G band.

Keywords: 5G/6G, graphene, lens, reconfigurable, satellite

Procedia PDF Downloads 142
8438 Evidence Based Approach on Beliefs and Perceptions on Mental Health Disorder and Substance Abuse: The Role of a Social Worker

Authors: Helena Baffoe

Abstract:

The US has developed numerous programs over the past 50 years to enhance the lives of those who suffer from mental health illnesses and substance abuse, as well as the effectiveness of their treatments. Despite these advances over the past 50 years, there hasn't been a corresponding improvement in American public attitudes and beliefs about mental health disorders and substance abuse. Highly publicized acts of violence frequently elicit comments that blame the perpetrator's perceived mental health disorder since such people are thought to be substance abusers. Despite these strong public beliefs and perception about mental disorder and substance abuse, concreate empirical evidence that entail this perception is lacking, and evidence of their effectiveness has not been integrated. A rich data was collected from Substance Abuse and Mental Health Services Administration (SAMHSA) with a hypothesis that people who are diagnosed with a mental health disorder are likely to be diagnosed with substance abuse using logit regression analysis and Instrumental Variable. It was found that depressive, anxiety, and trauma/stressor mental disorders constitute the most common mental disorder in the United States, and the study could not find statistically significant evidence that being diagnosed with these leading mental health disorders in the United States does necessarily imply that such a patient is diagnosed with substances abuse. Thus, the public has a misconception of mental health and substance abuse issues, and social workers' responsibilities are outlined in order to assist ameliorate this attitude and perception.

Keywords: mental health disorder, substance use, empirical evidence, logistic regression

Procedia PDF Downloads 74
8437 Effect of Quenching Medium on the Hardness of Dual Phase Steel Heat Treated at a High Temperature

Authors: Tebogo Mabotsa, Tamba Jamiru, David Ibrahim

Abstract:

Dual phase(DP) steel consists essentially of fine grained equiaxial ferrite and a dispersion of martensite. Martensite is the primary precipitate in DP steels, it is the main resistance to dislocation motion within the material. The objective of this paper is to present a relation between the intercritical annealing holding time and the hardness of a dual phase steel. The initial heat treatment involved heating the specimens to 1000oC and holding the sample at that temperature for 30 minutes. After the initial heat treatment, the samples were heated to 770oC and held for a varying amount of time at constant temperature. The samples were held at 30, 60, and 90 minutes respectively. After heating and holding the samples at the austenite-ferrite phase field, the samples were quenched in water, brine, and oil for each holding time. The experimental results proved that an equation for predicting the hardness of a dual phase steel as a function of the intercritical holding time is possible. The relation between intercritical annealing holding time and hardness of a dual phase steel heat treated at high temperatures is parabolic in nature. Theoretically, the model isdependent on the cooling rate because the model differs for each quenching medium; therefore, a universal hardness equation can be derived where the cooling rate is a variable factor.

Keywords: quenching medium, annealing temperature, dual phase steel, martensite

Procedia PDF Downloads 78
8436 Spectrophotometric Determination of 5-Aminosalicylic Acid in Pharmaceutical Samples

Authors: Chand Pasha

Abstract:

A Simple, accurate and precise spectrophotometric method for the quantitative analysis of determination of 5-aminosalicylic acid is described. This method is based on the reaction of 5-aminosalicylic acid with nitrite in acid medium to form diazonium ion, which is coupled with acetylacetone in basic medium to form azo dyes, which shows absorption maxima at 470 nm. The method obeys Beer’s law in the concentration range of 0.5-11.2 gml-1 of 5-aminosalicylic acid with acetylacetone. The molar absorptivity and Sandell’s sensitivity of 5-aminosalicylic acid -acetylacetone azo dye is 2.672 ×104 lmol-1cm-1, 5.731 × 10-3 gcm-2 respectively. The dye formed is stable for 10 hrs. The optimum reaction conditions and other analytical parameters are evaluated. Interference due to foreign organic compounds have been investigated. The method has been successfully applied to the determination of 5-aminosalicylic acid in pharmaceutical samples.

Keywords: spectrophotometry, diazotization, mesalazine, nitrite, acetylacetone

Procedia PDF Downloads 184
8435 Economic Characteristics of Bitcoin: "An Analytical Study"

Authors: Abdelhalem Shahen

Abstract:

The world is now experiencing a digital revolution and greatly accelerated technological developments, in addition to the transition from the economy in its traditional form to the digital economy, which has resulted in the emergence of new tools that are appropriate to those developments, and from this, this paper attempts to explore the economic characteristics of the bitcoin currency that circulated recently. Due to the many advantages that distinguish it from money in its traditional forms, which have a range of economic effects. The study found that Bitcoin is among the technological innovations, which contain a set of characteristics that are worth studying, those that make it the focus of attention, such as the digital currency, the peer-to-peer property, Lower and Faster Transaction Costs, transparency, decentralized control, privacy, and Double-Spending, as well as security and Cryptographic, and finally mining.

Keywords: Digital Economics, Digital Currencies, Bitcoin, Features of Bitcoin

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8434 Mapping of Electrical Energy Consumption Yogyakarta Province in 2014-2025

Authors: Alfi Al Fahreizy

Abstract:

Yogyakarta is one of the provinces in Indonesia that often get a power outage because of high load electrical consumption. The authors mapped the electrical energy consumption [GWh] for the province of Yogyakarta in 2014-2025 using LEAP (Long-range Energy Alternatives Planning system) software. This paper use BAU (Business As Usual) scenario. BAU scenario in which the projection is based on the assumption that growth in electricity consumption will run as normally as before. The goal is to be able to see the electrical energy consumption in the household sector, industry , business, social, government office building, and street lighting. The data is the data projected statistical population and consumption data electricity [GWh] 2010, 2011, 2012 in Yogyakarta province.

Keywords: LEAP, energy consumption, Yogyakarta, BAU

Procedia PDF Downloads 595
8433 Fuzzy Logic and Control Strategies on a Sump

Authors: Nasser Mohamed Ramli, Nurul Izzati Zulkifli

Abstract:

Sump can be defined as a reservoir which contains slurry; a mixture of solid and liquid or water, in it. Sump system is an unsteady process owing to the level response. Sump level shall be monitored carefully by using a good controller to avoid overflow. The current conventional controllers would not be able to solve problems with large time delay and nonlinearities, Fuzzy Logic controller is tested to prove its ability in solving the listed problems of slurry sump. Therefore, in order to justify the effectiveness and reliability of these controllers, simulation of the sump system was created by using MATLAB and the results were compared. According to the result obtained, instead of Proportional-Integral (PI) and Proportional-Integral and Derivative (PID), Fuzzy Logic controller showed the best result by offering quick response of 0.32 s for step input and 5 s for pulse generator, by producing small Integral Absolute Error (IAE) values that are 0.66 and 0.36 respectively.

Keywords: fuzzy, sump, level, controller

Procedia PDF Downloads 240
8432 An Eigen-Approach for Estimating the Direction-of Arrival of Unknown Number of Signals

Authors: Dia I. Abu-Al-Nadi, M. J. Mismar, T. H. Ismail

Abstract:

A technique for estimating the direction-of-arrival (DOA) of unknown number of source signals is presented using the eigen-approach. The eigenvector corresponding to the minimum eigenvalue of the autocorrelation matrix yields the minimum output power of the array. Also, the array polynomial with this eigenvector possesses roots on the unit circle. Therefore, the pseudo-spectrum is found by perturbing the phases of the roots one by one and calculating the corresponding array output power. The results indicate that the DOAs and the number of source signals are estimated accurately in the presence of a wide range of input noise levels.

Keywords: array signal processing, direction-of-arrival, antenna arrays, Eigenvalues, Eigenvectors, Lagrange multiplier

Procedia PDF Downloads 331
8431 Vapour Liquid Equilibrium Measurement of CO₂ Absorption in Aqueous 2-Aminoethylpiperazine (AEP)

Authors: Anirban Dey, Sukanta Kumar Dash, Bishnupada Mandal

Abstract:

Carbondioxide (CO2) is a major greenhouse gas responsible for global warming and fossil fuel power plants are the main emitting sources. Therefore the capture of CO2 is essential to maintain the emission levels according to the standards. Carbon capture and storage (CCS) is considered as an important option for stabilization of atmospheric greenhouse gases and minimizing global warming effects. There are three approaches towards CCS: Pre combustion capture where carbon is removed from the fuel prior to combustion, Oxy-fuel combustion, where coal is combusted with oxygen instead of air and Post combustion capture where the fossil fuel is combusted to produce energy and CO2 is removed from the flue gases left after the combustion process. Post combustion technology offers some advantage as existing combustion technologies can still be used without adopting major changes on them. A number of separation processes could be utilized part of post –combustion capture technology. These include (a) Physical absorption (b) Chemical absorption (c) Membrane separation (d) Adsorption. Chemical absorption is one of the most extensively used technologies for large scale CO2 capture systems. The industrially important solvents used are primary amines like Monoethanolamine (MEA) and Diglycolamine (DGA), secondary amines like diethanolamine (DEA) and Diisopropanolamine (DIPA) and tertiary amines like methyldiethanolamine (MDEA) and Triethanolamine (TEA). Primary and secondary amines react fast and directly with CO2 to form stable carbamates while Tertiary amines do not react directly with CO2 as in aqueous solution they catalyzes the hydrolysis of CO2 to form a bicarbonate ion and a protonated amine. Concentrated Piperazine (PZ) has been proposed as a better solvent as well as activator for CO2 capture from flue gas with a 10 % energy benefit compared to conventional amines such as MEA. However, the application of concentrated PZ is limited due to its low solubility in water at low temperature and lean CO2 loading. So following the performance of PZ its derivative 2-Aminoethyl piperazine (AEP) which is a cyclic amine can be explored as an activator towards the absorption of CO2. Vapour liquid equilibrium (VLE) in CO2 capture systems is an important factor for the design of separation equipment and gas treating processes. For proper thermodynamic modeling accurate equilibrium data for the solvent system over a wide range of temperatures, pressure and composition is essential. The present work focuses on the determination of VLE data for (AEP + H2O) system at 40 °C for various composition range.

Keywords: absorption, aminoethyl piperazine, carbondioxide, vapour liquid equilibrium

Procedia PDF Downloads 264
8430 Electrochemical Response Transductions of Graphenated-Polyaniline Nanosensor for Environmental Anthracene

Authors: O. Tovide, N. Jahed, N. Mohammed, C. E. Sunday, H. R. Makelane, R. F. Ajayi, K. M. Molapo, A. Tsegaye, M. Masikini, S. Mailu, A. Baleg, T. Waryo, P. G. Baker, E. I. Iwuoha

Abstract:

A graphenated–polyaniline (GR-PANI) nanocomposite sensor was constructed and used for the determination of anthracene. The direct electro-oxidation behavior of anthracene on the GR-PANI modified glassy carbon electrode (GCE) was used as the sensing principle. The results indicate thatthe response profile of the oxidation of anthracene on GR-PANI-modified GCE provides for the construction of sensor systems based onamperometric and potentiometric signal transductions. A dynamic linear range of 0.12- 100 µM anthracene and a detection limit of 0.044 µM anthracene were established for the sensor system.

Keywords: electrochemical sensors, environmental pollutants, graphenated-polymers, polyaromatic hydrocarbon

Procedia PDF Downloads 354
8429 Equivalent Circuit Modelling of Active Reflectarray Antenna

Authors: M. Y. Ismail, M. Inam

Abstract:

This paper presents equivalent circuit modeling of active planar reflectors which can be used for the detailed analysis and characterization of reflector performance in terms of lumped components. Equivalent circuit representation has been proposed for PIN diodes and liquid crystal based active planar reflectors designed within X-band frequency range. A very close agreement has been demonstrated between equivalent circuit results, 3D EM simulated results as well as measured scattering parameter results. In the case of measured results, a maximum discrepancy of 1.05dB was observed in the reflection loss performance, which can be attributed to the losses occurred during measurement process.

Keywords: Equivalent circuit modelling, planar reflectors, reflectarray antenna, PIN diode, liquid crystal

Procedia PDF Downloads 282
8428 Robust and Transparent Spread Spectrum Audio Watermarking

Authors: Ali Akbar Attari, Ali Asghar Beheshti Shirazi

Abstract:

In this paper, we propose a blind and robust audio watermarking scheme based on spread spectrum in Discrete Wavelet Transform (DWT) domain. Watermarks are embedded in the low-frequency coefficients, which is less audible. The key idea is dividing the audio signal into small frames, and magnitude of the 6th level of DWT approximation coefficients is modifying based upon the Direct Sequence Spread Spectrum (DSSS) technique. Also, the psychoacoustic model for enhancing in imperceptibility, as well as Savitsky-Golay filter for increasing accuracy in extraction, is used. The experimental results illustrate high robustness against most common attacks, i.e. Gaussian noise addition, Low pass filter, Resampling, Requantizing, MP3 compression, without significant perceptual distortion (ODG is higher than -1). The proposed scheme has about 83 bps data payload.

Keywords: audio watermarking, spread spectrum, discrete wavelet transform, psychoacoustic, Savitsky-Golay filter

Procedia PDF Downloads 194
8427 Statistically Significant Differences of Carbon Dioxide and Carbon Monoxide Emission in Photocopying Process

Authors: Kiurski S. Jelena, Kecić S. Vesna, Oros B. Ivana

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Experimental results confirmed the temporal variation of carbon dioxide and carbon monoxide concentration during the working shift of the photocopying process in a small photocopying shop in Novi Sad, Serbia. The statistically significant differences of target gases were examined with two-way analysis of variance without replication followed by Scheffe's post hoc test. The existence of statistically significant differences was obtained for carbon monoxide emission which is pointed out with F-values (12.37 and 31.88) greater than Fcrit (6.94) in contrary to carbon dioxide emission (F-values of 1.23 and 3.12 were less than Fcrit).  Scheffe's post hoc test indicated that sampling point A (near the photocopier machine) and second time interval contribute the most on carbon monoxide emission.

Keywords: analysis of variance, carbon dioxide, carbon monoxide, photocopying indoor, Scheffe's test

Procedia PDF Downloads 323
8426 Latent Factors of Severity in Truck-Involved and Non-Truck-Involved Crashes on Freeways

Authors: Shin-Hyung Cho, Dong-Kyu Kim, Seung-Young Kho

Abstract:

Truck-involved crashes have higher crash severity than non-truck-involved crashes. There have been many studies about the frequency of crashes and the development of severity models, but those studies only analyzed the relationship between observed variables. To identify why more people are injured or killed when trucks are involved in the crash, we must examine to quantify the complex causal relationship between severity of the crash and risk factors by adopting the latent factors of crashes. The aim of this study was to develop a structural equation or model based on truck-involved and non-truck-involved crashes, including five latent variables, i.e. a crash factor, environmental factor, road factor, driver’s factor, and severity factor. To clarify the unique characteristics of truck-involved crashes compared to non-truck-involved crashes, a confirmatory analysis method was used. To develop the model, we extracted crash data from 10,083 crashes on Korean freeways from 2008 through 2014. The results showed that the most significant variable affecting the severity of a crash is the crash factor, which can be expressed by the location, cause, and type of the crash. For non-truck-involved crashes, the crash and environment factors increase severity of the crash; conversely, the road and driver factors tend to reduce severity of the crash. For truck-involved crashes, the driver factor has a significant effect on severity of the crash although its effect is slightly less than the crash factor. The multiple group analysis employed to analyze the differences between the heterogeneous groups of drivers.

Keywords: crash severity, structural structural equation modeling (SEM), truck-involved crashes, multiple group analysis, crash on freeway

Procedia PDF Downloads 378
8425 Review of Various Designs and Development in Hydropower Turbines

Authors: Fatemeh Behrouzi, Adi Maimun, Mehdi Nakisa

Abstract:

The growth of population, rising fossil fuel prices which the fossil fuels are limited and decreased day by day, pollution problem due to use of fossil fuels and electrical demand are important role to encourage of using the green energy and renewable technologies. Among different renewable energy technologies, hydro power generation (large and small scale) is the prime choice in terms of contribution to the world's electricity generation by using water current turbines. Nowadays, researchers focus on design and development of different kind of turbines to capture hydro-power electricity generation as clean and reliable energy. This article is review about statues of water current turbines carried out to generate electricity from hydro-kinetic energy especially places that they do not have electricity, but they have access to the current water.

Keywords: water current turbine, renewable energy, hydro-power, mechanic

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8424 Ayurvastra: A Study on the Ancient Indian Textile for Healing

Authors: Reena Aggarwal

Abstract:

The use of textile chemicals in the various pre and post-textile manufacturing processes has made the textile industry conscious of its negative contribution to environmental pollution. Popular environmentally friendly fibers such as recycled polyester and organic cotton have been now increasingly used by fabrics and apparel manufacturers. However, after these textiles or the finished apparel are manufactured, they have to be dyed in the same chemical dyes that are harmful and toxic to the environment. Dyeing is a major area of concern for the environment as well as for people who have chemical sensitivities as it may cause nausea, breathing difficulties, seizures, etc. Ayurvastra or herbal medical textiles are one step ahead of the organic lifestyle, which supports the core concept of holistic well-being and also eliminates the impact of harmful chemicals and pesticides. There is a wide range of herbs that can be used not only for dyeing but also for providing medicinal properties to the textiles like antibacterial, antifungal, antiseptic, antidepressant and for treating insomnia, skin diseases, etc. The concept of herbal dyeing of fabric is to manifest herbal essence in every aspect of clothing, i.e., from production to end-use, additionally to eliminate the impact of harmful chemical dyes and chemicals which are known to result in problems like skin rashes, headache, trouble concentrating, nausea, diarrhea, fatigue, muscle and joint pain, dizziness, difficulty breathing, irregular heartbeat and seizures. Herbal dyeing or finishing on textiles will give an extra edge to the textiles as it adds an extra function to the fabric. The herbal extracts can be applied to the textiles by a simple process like the pad dry cure method and mainly acts on the human body through the skin for aiding in the treatment of disease or managing the medical condition through its herbal properties. This paper, therefore, delves into producing Ayurvastra, which is a perfect amalgamation of cloth and wellness. The aim of the paper is to design and create herbal disposable and non-disposable medical textile products acting mainly topically (through the skin) for providing medicinal properties/managing medical conditions. Keeping that in mind, a range of antifungal socks and antibacterial napkins treated with turmeric and aloe vera were developed, which are recommended for the treatment of fungal and bacterial infections, respectively. Both Herbal Antifungal socks and Antibacterial napkins have proved to be efficient enough in managing and treating fungal and bacterial infections of the skin, respectively.

Keywords: ayurvastra, ayurveda, herbal, pandemic, sustainable

Procedia PDF Downloads 126
8423 Force Sensing Resistor Testing of Hand Forces and Grasps during Daily Functional Activities in the Covid-19 Pandemic

Authors: Monique M. Keller, Roline Barnes, Corlia Brandt

Abstract:

Introduction Scientific evidence on the hand forces and the types of grasps measurement during daily tasks are lacking, leaving a gap in the field of hand rehabilitation and robotics. Measuring the grasp forces and types produced by the individual fingers during daily functional tasks is valuable to inform and grade rehabilitation practices for second to fifth metacarpal fractures with robust scientific evidence. Feix et al, 2016 identified the most extensive and complete grasp study that resulted in the GRASP taxonomy. Covid-19 virus changed data collection across the globe and safety precautions in research are essential to ensure the health of participants and researchers. Methodology A cross-sectional study investigated six healthy adults aged 20 to 59 years, pilot participants’ hand forces during 105 tasks. The tasks were categorized into five sections namely, personal care, transport and moving around, home environment and inside, gardening and outside, and office. The predominant grasp of each task was identified guided by the GRASP Taxonomy. Grasp forces were measured with 13mm force-sensing resistors glued onto a glove attached to each of the dominant and non-dominant hand’s individual fingers. Testing equipment included Flexiforce 13millimetres FSR .5" circle, calibrated prior to testing, 10k 1/4w resistors, Arduino pro mini 5.0v – compatible, Esp-01-kit, Arduino uno r3 – compatible board, USB ab cable - 1m, Ftdi ft232 mini USB to serial, Sil 40 inline connectors, ribbon cable combo male header pins, female to female, male to female, two gloves, glue to attach the FSR to glove, Arduino software programme downloaded on a laptop. Grip strength measurements with Jamar dynamometer prior to testing and after every 25 daily tasks were taken to will avoid fatigue and ensure reliability in testing. Covid-19 precautions included wearing face masks at all times, screening questionnaires, temperatures taken, wearing surgical gloves before putting on the testing gloves 1.5 metres long wires attaching the FSR to the Arduino to maintain social distance. Findings Predominant grasps observed during 105 tasks included, adducted thumb (17), lateral tripod (10), prismatic three fingers (12), small diameter (9), prismatic two fingers (9), medium wrap (7), fixed hook (5), sphere four fingers (4), palmar (4), parallel extension (4), index finger extension (3), distal (3), power sphere (2), tripod (2), quadpod (2), prismatic four fingers (2), lateral (2), large-diameter (2), ventral (2), precision sphere (1), palmar pinch (1), light tool (1), inferior pincher (1), and writing tripod (1). Range of forces applied per category, personal care (1-25N), transport and moving around (1-9 N), home environment and inside (1-41N), gardening and outside (1-26.5N), and office (1-20N). Conclusion Scientifically measurements of finger forces with careful consideration to types of grasps used in daily tasks should guide rehabilitation practices and robotic design to ensure a return to the full participation of the individual into the community.

Keywords: activities of daily living (ADL), Covid-19, force-sensing resistors, grasps, hand forces

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8422 Leveraging Remote Assessments and Central Raters to Optimize Data Quality in Rare Neurodevelopmental Disorders Clinical Trials

Authors: Pamela Ventola, Laurel Bales, Sara Florczyk

Abstract:

Background: Fully remote or hybrid administration of clinical outcome measures in rare neurodevelopmental disorders trials is increasing due to the ongoing pandemic and recognition that remote assessments reduce the burden on families. Many assessments in rare neurodevelopmental disorders trials are complex; however, remote/hybrid trials readily allow for the use of centralized raters to administer and score the scales. The use of centralized raters has many benefits, including reducing site burden; however, a specific impact on data quality has not yet been determined. Purpose: The current study has two aims: a) evaluate differences in data quality between administration of a standardized clinical interview completed by centralized raters compared to those completed by site raters and b) evaluate improvement in accuracy of scoring standardized developmental assessments when scored centrally compared to when scored by site raters. Methods: For aim 1, the Vineland-3, a widely used measure of adaptive functioning, was administered by site raters (n= 52) participating in one of four rare disease trials. The measure was also administered as part of two additional trials that utilized central raters (n=7). Each rater completed a comprehensive training program on the assessment. Following completion of the training, each clinician completed a Vineland-3 with a mock caregiver. Administrations were recorded and reviewed by a neuropsychologist for administration and scoring accuracy. Raters were able to certify for the trials after demonstrating an accurate administration of the scale. For site raters, 25% of each rater’s in-study administrations were reviewed by a neuropsychologist for accuracy of administration and scoring. For central raters, the first two administrations and every 10th administration were reviewed. Aim 2 evaluated the added benefit of centralized scoring on the accuracy of scoring of the Bayley-3, a comprehensive developmental assessment widely used in rare neurodevelopmental disorders trials. Bayley-3 administrations across four rare disease trials were centrally scored. For all administrations, the site rater who administered the Bayley-3 scored the scale, and a centralized rater reviewed the video recordings of the administrations and also scored the scales to confirm accuracy. Results: For aim 1, site raters completed 138 Vineland-3 administrations. Of the138 administrations, 53 administrations were reviewed by a neuropsychologist. Four of the administrations had errors that compromised the validity of the assessment. The central raters completed 180 Vineland-3 administrations, 38 administrations were reviewed, and none had significant errors. For aim 2, 68 administrations of the Bayley-3 were reviewed and scored by both a site rater and a centralized rater. Of these administrations, 25 had errors in scoring that were corrected by the central rater. Conclusion: In rare neurodevelopmental disorders trials, sample sizes are often small, so data quality is critical. The use of central raters inherently decreases site burden, but it also decreases rater variance, as illustrated by the small team of central raters (n=7) needed to conduct all of the assessments (n=180) in these trials compared to the number of site raters (n=53) required for even fewer assessments (n=138). In addition, the use of central raters dramatically improves the quality of scoring the assessments.

Keywords: neurodevelopmental disorders, clinical trials, rare disease, central raters, remote trials, decentralized trials

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8421 Development of 420 mm Diameter Silicon Crystal Growth Using Continuous Czochralski Process

Authors: Ilsun Pang, Kwanghun Kim, Sungsun Baik

Abstract:

Large diameter Si wafer is used as semiconductor substrate. Large diameter Si crystal ingot should be needed in order to increase wafer size. To make convection of large silicon melt stable, magnetic field is normally applied, but magnetic field is expensive and it is not proper to stabilize the large Si melt. To solve the problem, we propose a continuous Czochralski process which can be applied to small melt without magnetic field. We used granule poly, which has size distribution of 1~3 mm and is easily supplied in double crucible during silicon ingot growth. As the result, we produced 420 mm diameter ingot. In this paper, we describe an experimental study on crystal growth of large diameter silicon by Continuous Czochralski process.

Keywords: Czochralski, ingot, silicon crystal, wafer

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8420 Fluid Flow and Heat Transfer Characteristics Investigation in Spray Cooling Systems Using Nanofluids

Authors: Lee Derk Huan, Nur Irmawati

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This paper aims to investigate the heat transfer and fluid flow characteristics of nanofluids used in spray cooling systems. The effect of spray height, type of nanofluids and concentration of nanofluids are numerically investigated. Five different nanofluids such as AgH2O, Al2O3, CuO, SiO2 and TiO2 with volume fraction range of 0.5% to 2.5% are used. The results revealed that the heat transfer performance decreases as spray height increases. It is found that TiO2 has the highest transfer coefficient among other nanofluids. In dilute spray conditions, low concentration of nanofluids is observed to be more effective in heat removal in a spray cooling system.

Keywords: numerical investigation, spray cooling, heat transfer, nanofluids

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8419 Endothelin Cells and Its Molecular Biology and Microbiology

Authors: Chro Kawyan

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Endothelin-1 (ET-1), the principal individual from the newfound mammalian endothelin group of organically dynamic peptides, was initially distinguished as a 21 buildup powerful vasoconstrictor peptide in vascular endothelial cells. However, it has since been demonstrated to have a wide range of pharmacological activities in tissues both inside and outside the cardiovascular system. Additionally, peptides that have a striking resemblance to ET-1 have been identified as the primary toxic component of snake venom. In addition, late examinations have proposed that warm blooded creatures, including people, produce three unmistakable individuals from this peptide family, ET-1, ET-2 and ET-J, which might have various profiles of organic action and may follow up on particular subtypes of endothelin receptor. Masashi Yanagisawa and Tomoh Masaki survey the ongoing status of the organic chemistry and sub-atomic science of endothelin.

Keywords: thelin, microbiology, molecular biology, cell

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8418 An Efficient Automated Radiation Measuring System for Plasma Monopole Antenna

Authors: Gurkirandeep Kaur, Rana Pratap Yadav

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This experimental study is aimed to examine the radiation characteristics of different plasma structures of a surface wave-driven plasma antenna by an automated measuring system. In this study, a 30 cm long plasma column of argon gas with a diameter of 3 cm is excited by surface wave discharge mechanism operating at 13.56 MHz with RF power level up to 100 Watts and gas pressure between 0.01 to 0.05 mb. The study reveals that a single structured plasma monopole can be modified into an array of plasma antenna elements by forming multiple striations or plasma blobs inside the discharge tube by altering the values of plasma properties such as working pressure, operating frequency, input RF power, discharge tube dimensions, i.e., length, radius, and thickness. It is also reported that plasma length, electron density, and conductivity are functions of operating plasma parameters and controlled by changing working pressure and input power. To investigate the antenna radiation efficiency for the far-field region, an automation-based radiation measuring system has been fabricated and presented in detail. This developed automated system involves a combined setup of controller, dc servo motors, vector network analyzer, and computing device to evaluate the radiation intensity, directivity, gain and efficiency of plasma antenna. In this system, the controller is connected to multiple motors for moving aluminum shafts in both elevation and azimuthal plane whereas radiation from plasma monopole antenna is measured by a Vector Network Analyser (VNA) which is further wired up with the computing device to display radiations in polar plot forms. Here, the radiation characteristics of both continuous and array plasma monopole antenna have been studied for various working plasma parameters. The experimental results clearly indicate that the plasma antenna is as efficient as a metallic antenna. The radiation from plasma monopole antenna is significantly influenced by plasma properties which provides a wider range in radiation pattern where desired radiation parameters like beam-width, the direction of radiation, radiation intensity, antenna efficiency, etc. can be achieved in a single monopole. Due to its wide range of selectivity in radiation pattern; this can meet the demands of wider bandwidth to get high data speed in communication systems. Moreover, this developed system provides an efficient and cost-effective solution for measuring the radiation pattern in far-field zone for any kind of antenna system.

Keywords: antenna radiation characteristics, dynamically reconfigurable, plasma antenna, plasma column, plasma striations, surface wave

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8417 Effective Counseling Techniques Working with At-Risk Youth in Residential and Outpatient Settings

Authors: David A. Scott, Michelle G. Scott

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The problem of juvenile crime, school suspensions and oppositional behaviors indicates a need for a wide range of intervention programs for at-risk youth. Juvenile court systems and mental health agencies are examining alternative ways to deal with at-risk youth that will allow the adolescent to live within their home community. The previous trend that treatment away from home is more effective than treatment near one's community has shifted. Research now suggests that treatment be close to home for several reasons, such as increased treatment success, parental involvement, and reduced costs. Treatment options consist of a wide range of interventions, including outpatient, inpatient, and community-based services (therapeutic group homes, foster care and in-home preservation services). The juvenile justice system, families and other mental health agencies continue to seek the most effective treatment for at-risk youth in their communities. This research examines two possible treatment modalities, a multi-systemic outpatient program and a residential program. Research examining effective, evidence- based counseling will be discussed during this presentation. The presenter recently completed a three-year research grant examining effective treatment modalities for at-risk youth participating in a multi-systemic program. The presenter has also been involved in several research activities gathering data on effective techniques used in residential programs. The data and discussion will be broken down into two parts, each discussing one of the treatment modalities mentioned above. Data on the residential programs was collected on both a sample of 740 at- risk youth over a five-year period and also a sample of 63 participants during a one-year period residing in a residential programs. The effectiveness of these residential services was measured in three ways: services are evaluated by primary referral sources; follow-up data is obtained at various intervals after program participation to measure recidivism (what percentage got back into trouble with the Department of Juvenile Justice); and a more sensitive, "Offense Seriousness Score", has been computed and analyzed prior to, during and after treatment in the residential program. Data on the multi-systemic program was gathered over the past three years on 190 participants. Research will discuss pre and post test results, recidivism rates, academic performance, parental involvement, and effective counseling treatment modalities.

Keywords: at-risk youth, group homes, therapeutic group homes, recidivism rates

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8416 Influence of Kneading Conditions on the Textural Properties of Alumina Catalysts Supports for Hydrotreating

Authors: Lucie Speyer, Vincent Lecocq, Séverine Humbert, Antoine Hugon

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Mesoporous alumina is commonly used as a catalyst support for the hydrotreating of heavy petroleum cuts. The process of fabrication usually involves: the synthesis of the boehmite AlOOH precursor, a kneading-extrusion step, and a calcination in order to obtain the final alumina extrudates. Alumina is described as a complex porous medium, generally agglomerates constituted of aggregated nanocrystallites. Its porous texture directly influences the active phase deposition and mass transfer, and the catalytic properties. Then, it is easy to figure out that each step of the fabrication of the supports has a role on the building of their porous network, and has to be well understood to optimize the process. The synthesis of boehmite by precipitation of aluminum salts was extensively studied in the literature and the effect of various parameters, such as temperature or pH, are known to influence the size and shape of the crystallites and the specific surface area of the support. The calcination step, through the topotactic transition from boehmite to alumina, determines the final properties of the support and can tune the surface area, pore volume and pore diameters from those of boehmite. However, the kneading extrusion step has been subject to a very few studies. It generally consists in two steps: an acid, then a basic kneading, where the boehmite powder is introduced in a mixer and successively added with an acid and a base solution to form an extrudable paste. During the acid kneading, the induced positive charges on the hydroxyl surface groups of boehmite create an electrostatic repulsion which tends to separate the aggregates and even, following the conditions, the crystallites. The basic kneading, by reducing the surface charges, leads to a flocculation phenomenon and can control the reforming of the overall structure. The separation and reassembling of the particles constituting the boehmite paste have a quite obvious influence on the textural properties of the material. In this work, we are focused on the influence of the kneading step on the alumina catalysts supports. Starting from an industrial boehmite, extrudates are prepared using various kneading conditions. The samples are studied by nitrogen physisorption in order to analyze the evolution of the textural properties, and by synchrotron small-angle X-ray scattering (SAXS), a more original method which brings information about agglomeration and aggregation of the samples. The coupling of physisorption and SAXS enables a precise description of the samples, as same as an accurate monitoring of their evolution as a function of the kneading conditions. These ones are found to have a strong influence of the pore volume and pore size distribution of the supports. A mechanism of evolution of the texture during the kneading step is proposed and could be attractive in order to optimize the texture of the supports and then, their catalytic performances.

Keywords: alumina catalyst support, kneading, nitrogen physisorption, small-angle X-ray scattering

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8415 Developing Motorized Spectroscopy System for Tissue Scanning

Authors: Tuba Denkceken, Ayse Nur Sarı, Volkan Ihsan Tore, Mahmut Denkceken

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The aim of the presented study was to develop a newly motorized spectroscopy system. Our system is composed of probe and motor parts. The probe part consists of bioimpedance and fiber optic components that include two platinum wires (each 25 micrometer in diameter) and two fiber cables (each 50 micrometers in diameter) respectively. Probe was examined on tissue phantom (polystyrene microspheres with different diameters). In the bioimpedance part of the probe current was transferred to the phantom and conductivity information was obtained. Adjacent two fiber cables were used in the fiber optic part of the system. Light was transferred to the phantom by fiber that was connected to the light source and backscattered light was collected with the other adjacent fiber for analysis. It is known that the nucleus expands and the nucleus-cytoplasm ratio increases during the cancer progression in the cell and this situation is one of the most important criteria for evaluating the tissue for pathologists. The sensitivity of the probe to particle (nucleus) size in phantom was tested during the study. Spectroscopic data obtained from our system on phantom was evaluated by multivariate statistical analysis. Thus the information about the particle size in the phantom was obtained. Bioimpedance and fiber optic experiments results which were obtained from polystyrene microspheres showed that the impedance value and the oscillation amplitude were increasing while the size of particle was enlarging. These results were compatible with the previous studies. In order to motorize the system within the motor part, three driver electronic circuits were designed primarily. In this part, supply capacitors were placed symmetrically near to the supply inputs which were used for balancing the oscillation. Female capacitors were connected to the control pin. Optic and mechanic switches were made. Drivers were structurally designed as they could command highly calibrated motors. It was considered important to keep the drivers’ dimension as small as we could (4.4x4.4x1.4 cm). Then three miniature step motors were connected to each other along with three drivers. Since spectroscopic techniques are quantitative methods, they yield more objective results than traditional ones. In the future part of this study, it is planning to get spectroscopic data that have optic and impedance information from the cell culture which is normal, low metastatic and high metastatic breast cancer. In case of getting high sensitivity in differentiated cells, it might be possible to scan large surface tissue areas in a short time with small steps. By means of motorize feature of the system, any region of the tissue will not be missed, in this manner we are going to be able to diagnose cancerous parts of the tissue meticulously. This work is supported by The Scientific and Technological Research Council of Turkey (TÜBİTAK) through 3001 project (115E662).

Keywords: motorized spectroscopy, phantom, scanning system, tissue scanning

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