Search results for: functional properties
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11076

Search results for: functional properties

5076 Geometrically Linear Symmetric Free Vibration Analysis of Sandwich Beam

Authors: Ibnorachid Zakaria, El Bikri Khalid, Benamar Rhali, Farah Abdoun

Abstract:

The aim of the present work is to study the linear free symmetric vibration of three-layer sandwich beam using the energy method. The zigzag model is used to describe the displacement field. The theoretical model is based on the top and bottom layers behave like Euler-Bernoulli beams while the core layer like a Timoshenko beam. Based on Hamilton’s principle, the governing equation of motion sandwich beam is obtained in order to calculate the linear frequency parameters for a clamped-clamped and simple supported-simple-supported beams. The effects of material properties and geometric parameters on the natural frequencies are also investigated.

Keywords: linear vibration, sandwich, shear deformation, Timoshenko zig-zag model

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5075 From User's Requirements to UML Class Diagram

Authors: Zeineb Ben Azzouz, Wahiba Ben Abdessalem Karaa

Abstract:

The automated extraction of UML class diagram from natural language requirements is a highly challenging task. Many approaches, frameworks and tools have been presented in this field. Nonetheless, the experiments of these tools have shown that there is no approach that can work best all the time. In this context, we propose a new accurate approach to facilitate the automatic mapping from textual requirements to UML class diagram. Our new approach integrates the best properties of statistical Natural Language Processing (NLP) techniques to reduce ambiguity when analysing natural language requirements text. In addition, our approach follows the best practices defined by conceptual modelling experts to determine some patterns indispensable for the extraction of basic elements and concepts of the class diagram. Once the relevant information of class diagram is captured, a XMI document is generated and imported with a CASE tool to build the corresponding UML class diagram.

Keywords: class diagram, user’s requirements, XMI, software engineering

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5074 Analysis of Extracellular Vesicles Interactomes of two Isoforms of Tau Protein via SHSY-5Y Cell Lines

Authors: Mohammad Aladwan

Abstract:

Alzheimer’s disease (AD) is a widespread dementing illness with a complex and poorly understood etiology. An important role in improving our understanding of the AD process is the modeling of disease-associated changes in tau protein phosphorylation, a protein known to mediate events essential to the onset and progression of AD. A main feature of AD is the abnormal phosphorylation of tau protein and the presence of neurofibrillary tangles. In order to evaluate the respective roles of the microtubule-binding region (MTBR) and alternatively spliced exons in the N-terminal projection domains in AD, we have constructed SHSY-5Y cell lines that stably overexpress four different species of tau protein (4R2N, 4R0N, N(E-2), N(E+2)). Since the toxicity and spreading of tau lesions in AD depends on the interactions of tau with other proteins, we have performed a proteomic analysis of exosome-fraction interactomes for cell lysates and media samples that were isolated from SHSY-5Y cell lines. Functional analysis of tau interactomes based on gene ontology (GO) terms was performed using the String 10.5 database program. The highest number of exosomes proteomes and tau associated proteins were found with 4R2N isoform (2771 and 159) in cell lysate and they have a high strength of connectivity (78%) between proteins, while N(E-2) isoform in the media proteomes has the highest number of proteins and tau associated protein (1829 and 205). Moreover, known AD markers were significantly enriched in secreted interactomes relative to lysate interactomes in the SHSY-5Y cells of tau isoforms lacking exons 2 and 3 in the N-terminal. The lack of exon 2 (E-2) from tau protein can be mediated by tau secretion and spreading to different cells. Enriched functions in the secreted E-2 interactome include signaling and developmental pathways that have been linked to a) tau misprocessing and lesion development and b) tau secretion and which, therefore, could play novel roles in AD pathogenesis.

Keywords: Alzheimer's disease, dementia, tau protein, neurodegenration disease

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5073 Psychometric Validation of Czech Version of Spiritual Needs Assessment for Patients: The First Part of Research

Authors: Lucie Mrackova, Helena Kisvetrova

Abstract:

Spirituality is an integral part of human life. In a secular environment, spiritual needs are often overlooked, especially in acute nursing care. Spiritual needs assessment for patients (SNAP), which also exists in the Czech version (SNAP-CZ), can be used for objective evaluation. The aim of this study was to measure the psychometric properties of SNAP-CZ and to find correlations between SNAP-CZ and sociodemographic and clinical variables. A cross-sectional study with tools assessing spiritual needs (SNAP-CZ), anxiety (Beck Anxiety Inventory; BAI), depression (Beck Depression Inventory; BDI), pain (Visual Analogue Scale; VAS), self-sufficiency (Barthel Index; BI); cognitive function (Montreal Cognitive Test; MoCa) and selected socio-demographic data was performed. The psychometric properties of SNAP-CZ were tested using factor analysis, reliability and validity tests, and correlations between the questionnaire and sociodemographic data and clinical variables. Internal consistency was established with Cronbach’s alfa for the overall score, respective domains, and individual items. Reliability was assessed by test-retest by Interclass correlation coefficient (ICC). Data for correlation analysis were processed according to Pearson's correlation coefficient. The study included 172 trauma patients (the mean age = 40.6 ± 12.1 years) who experienced polytrauma or severe monotrauma. There were a total of 106 (61.6%) male subjects, 140 (81.4%) respondents identified themselves as non-believers. The full-scale Cronbach's alpha was 0.907. The test-retest showed the reliability of the individual domains in the range of 0.924 to 0.960 ICC. Factor analysis resulted in a three-factor solution (psychosocial needs (alfa = 0.788), spiritual needs (alfa = 0.886) and religious needs (alfa = 0.841)). Correlation analysis using Pearson's correlation coefficient showed that the domain of psychosocial needs significantly correlated only with gender (r = 0.178, p = 0.020). Males had a statistically significant lower average value in this domain (mean = 12.5) compared to females (mean = 13.8). The domain of spiritual needs significantly correlated with gender (r = 0.199, p = 0.009), social status (r = 0.156, p = 0.043), faith (r = -0.250, p = 0.001), anxiety (r = 0.194, p = 0.011) and depression (r = 0.155, p = 0.044). The domain of religious needs significantly correlated with age (r = 0,208, p = 0,007), education (r = -0,161, p = 0,035), faith (r = -0,575, p < 0,0001) and depression (r = 0,179, p = 0,019). Overall, the whole SNAP scale significantly correlated with gender (r = 0.219, p = 0.004), social status (r = 0.175, p = 0.023), faith (r = -0.334, p <0.0001), anxiety (r = 0.177, p = 0.022) and depression (r = 0.173, p = 0.025). The results of this study corroborate the reliability of the SNAP-CZ and support its future use in the nursing care of trauma patients in a secular society. Acknowledgment: The study was supported by grant nr. IGA_FZV_2020_003.

Keywords: acute nursing care, assessment of spiritual needs, patient, psychometric validation, spirituality

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5072 Development of a Quick On-Site Pass/Fail Test for the Evaluation of Fresh Concrete Destined for Application as Exposed Concrete

Authors: Laura Kupers, Julie Piérard, Niki Cauberg

Abstract:

The use of exposed concrete (sometimes referred to as architectural concrete), keeps gaining popularity. Exposed concrete has the advantage to combine the structural properties of concrete with an aesthetic finish. However, for a successful aesthetic finish, much attention needs to be paid to the execution (formwork, release agent, curing, weather conditions…), the concrete composition (choice of the raw materials and mix proportions) as well as to its fresh properties. For the latter, a simple on-site pass/fail test could halt the casting of concrete not suitable for architectural concrete and thus avoid expensive repairs later. When architects opt for an exposed concrete, they usually want a smooth, uniform and nearly blemish-free surface. For this choice, a standard ‘construction’ concrete does not suffice. An aesthetic surface finishing requires the concrete to contain a minimum content of fines to minimize the risk of segregation and to allow complete filling of more complex shaped formworks. The concrete may neither be too viscous as this makes it more difficult to compact and it increases the risk of blow holes blemishing the surface. On the other hand, too much bleeding may cause color differences on the concrete surface. An easy pass/fail test, which can be performed on the site just before the casting, could avoid these problems. In case the fresh concrete fails the test, the concrete can be rejected. Only in case the fresh concrete passes the test, the concrete would be cast. The pass/fail tests are intended for a concrete with a consistency class S4. Five tests were selected as possible onsite pass/fail test. Two of these tests already exist: the K-slump test (ASTM C1362) and the Bauer Filter Press Test. The remaining three tests were developed by the BBRI in order to test the segregation resistance of fresh concrete on site: the ‘dynamic sieve stability test’, the ‘inverted cone test’ and an adapted ‘visual stability index’ (VSI) for the slump and flow test. These tests were inspired by existing tests for self-compacting concrete, for which the segregation resistance is of great importance. The suitability of the fresh concrete mixtures was also tested by means of a laboratory reference test (resistance to segregation) and by visual inspection (blow holes, structure…) of small test walls. More than fifteen concrete mixtures of different quality were tested. The results of the pass/fail tests were compared with the results of this laboratory reference test and the test walls. The preliminary laboratory results indicate that concrete mixtures ‘suitable’ for placing as exposed concrete (containing sufficient fines, a balanced grading curve etc.) can be distinguished from ‘inferior’ concrete mixtures. Additional laboratory tests, as well as tests on site, will be conducted to confirm these preliminary results and to set appropriate pass/fail values.

Keywords: exposed concrete, testing fresh concrete, segregation resistance, bleeding, consistency

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5071 Perceptual Organization within Temporal Displacement

Authors: Michele Sinico

Abstract:

The psychological present has an actual extension. When a sequence of instantaneous stimuli falls in this short interval of time, observers perceive a compresence of events in succession and the temporal order depends on the qualitative relationships between the perceptual properties of the events. Two experiments were carried out to study the influence of perceptual grouping, with and without temporal displacement, on the duration of auditory sequences. The psychophysical method of adjustment was adopted. The first experiment investigated the effect of temporal displacement of a white noise on sequence duration. The second experiment investigated the effect of temporal displacement, along the pitch dimension, on temporal shortening of sequence. The results suggest that the temporal order of sounds, in the case of temporal displacement, is organized along the pitch dimension.

Keywords: time perception, perceptual present, temporal displacement, Gestalt laws of perceptual organization

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5070 Numerical Investigation on Transient Heat Conduction through Brine-Spongy Ice

Authors: S. R. Dehghani, Y. S. Muzychka, G. F. Naterer

Abstract:

The ice accretion of salt water on cold substrates creates brine-spongy ice. This type of ice is a mixture of pure ice and liquid brine. A real case of creation of this type of ice is superstructure icing which occurs on marine vessels and offshore structures in cold and harsh conditions. Transient heat transfer through this medium causes phase changes between brine pockets and pure ice. Salt rejection during the process of transient heat conduction increases the salinity of brine pockets to reach a local equilibrium state. In this process the only effect of passing heat through the medium is not changing the sensible heat of the ice and brine pockets; latent heat plays an important role and affects the mechanism of heat transfer. In this study, a new analytical model for evaluating heat transfer through brine-spongy ice is suggested. This model considers heat transfer and partial solidification and melting together. Properties of brine-spongy ice are obtained using properties of liquid brine and pure ice. A numerical solution using Method of Lines discretizes the medium to reach a set of ordinary differential equations. Boundary conditions are chosen using one of the applicable cases of this type of ice; one side is considered as a thermally isolated surface, and the other side is assumed to be suddenly affected by a constant temperature boundary. All cases are evaluated in temperatures between -20 C and the freezing point of brine-spongy ice. Solutions are conducted using different salinities from 5 to 60 ppt. Time steps and space intervals are chosen properly to maintain the most stable and fast solution. Variation of temperature, volume fraction of brine and brine salinity versus time are the most important outputs of this study. Results show that transient heat conduction through brine-spongy ice can create a various range of salinity of brine pockets from the initial salinity to that of 180 ppt. The rate of variation of temperature is found to be slower for high salinity cases. The maximum rate of heat transfer occurs at the start of the simulation. This rate decreases as time passes. Brine pockets are smaller at portions closer to the colder side than that of the warmer side. A the start of the solution, the numerical solution tends to increase instabilities. This is because of sharp variation of temperature at the start of the process. Changing the intervals improves the unstable situation. The analytical model using a numerical scheme is capable of predicting thermal behavior of brine spongy ice. This model and numerical solutions are important for modeling the process of freezing of salt water and ice accretion on cold structures.

Keywords: method of lines, brine-spongy ice, heat conduction, salt water

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5069 Poly(Lactic Acid) Based Flexible Films

Authors: Fathilahbinti Ali, Jamarosliza Jamaluddin, Arun Kumar Upadhyay

Abstract:

Poly(lactic acid) (PLA) is a biodegradable polymer which has good mechanical properties, however, its brittleness limits its usage especially in packaging materials. Therefore, in this work, PLA based polyurethane films were prepared by synthesizing with different types of isocyanates; methylene diisocyanate (MDI) and hexamethylene diisocyanates (HDI). For this purpose, PLA based polyurethane must have good strength and flexibility. Therefore, polycaprolactone which has better flexibility were prepared with PLA. An effective way to endow polylactic acid with toughness is through chain-extension reaction of the polylactic acid pre-polymer with polycaprolactone used as chain extender. Polyurethane prepared from MDI showed brittle behaviour, while, polyurethane prepared from HDI showed flexibility at same concentrations.

Keywords: biodegradable polymer, flexible, poly(lactic acid), polyurethane

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5068 Research of Interaction between Layers of Compressed Composite Columns

Authors: Daumantas Zidanavicius

Abstract:

In order to investigate the bond between concrete and steel in the circular steel tube column filled with concrete, the 7 series of specimens were tested with the same geometrical parameters but different concrete properties. Two types of specimens were chosen. For the first type, the expansive additives to the concrete mixture were taken to increase internal forces. And for the second type, mechanical components were used. All 7 series of the short columns were modeled by FEM and tested experimentally. In the work, big attention was taken to the bond-slip models between steel and concrete. Results show that additives to concrete let increase the bond strength up to two times and the mechanical anchorage –up to 6 times compared to control specimens without additives and anchorage.

Keywords: concrete filled steel tube, push-out test, bond slip relationship, bond stress distribution

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5067 Exchange Rate Variation and Balance of Payments: The Nigerian Experience (1970-2012)

Authors: Vitus Onyebuchim Onyemailu, Olive Obianuju Okalibe

Abstract:

The study tried to examine relationship between exchange rate variations on the balance of payments in Nigeria from 1970 to 2012. Using time series on econometric measures such as Granger causality and ordinary least square (OLS), the study found that exchange rate movements especially the depreciation of naira has not contributed significantly on the balance of payments under the year of the study. The granger result conform the Marshall-Lerner short and long run prepositions that exchange rate devaluation enhances balance of payments. On disaggregation exchange rate granger causes current and capital account balances give the Nigeria data from 1970 to 2012. Overall in the long run OLS regression analysis, exchange rate on semi log functional form, exchange rate variation did not record significant effect on balance of payment equation. This height was also maintained in the current or trade balance which does not match the Marshall-Lerner. The capital account balance in reverse reported a significant impact of exchange rate variability on the capital account balance. Finally, on exchange rate determination equation, where many fundamentals were considered including lagged of exchange rate. Thus, the lagged of exchange rate recorded a positive and significant influence on the present exchange rate. This means that players in the financial markets usually out plays authority’s policy’s stances through their speculative tendencies. The work therefore, recommend that effort should be made by the authorities to providing enabling environment for production of goods and services to triumph in order to take advantages of steady devaluation of its currency. This is done by providing infrastructure, provision of science and technology. Thus, when this is done Nigeria would be able to have competitive power against the rest of the world.

Keywords: exchange rate variation, balance of payments, current account, capital account, Marshall-Lerner hypothesis

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5066 Mapping the Early History of Common Law Education in England, 1292-1500

Authors: Malcolm Richardson, Gabriele Richardson

Abstract:

This paper illustrates how historical problems can be studied successfully using GIS even in cases in which data, in the modern sense, is fragmentary. The overall problem under investigation is how early (1300-1500) English schools of Common Law moved from apprenticeship training in random individual London inns run in part by clerks of the royal chancery to become what is widely called 'the Third University of England,' a recognized system of independent but connected legal inns. This paper focuses on the preparatory legal inns, called the Inns of Chancery, rather than the senior (and still existing) Inns of Court. The immediate problem studied in this paper is how the junior legal inns were organized, staffed, and located from 1292 to about 1500, and what maps tell us about the role of the chancery clerks as managers of legal inns. The authors first uncovered the names of all chancery clerks of the period, most of them unrecorded in histories, from archival sources in the National Archives, Kew. Then they matched the names with London property leases. Using ArcGIS, the legal inns and their owners were plotted on a series of maps covering the period 1292 to 1500. The results show a distinct pattern of ownership of the legal inns and suggest a narrative that would help explain why the Inns of Chancery became serious centers of learning during the fifteenth century. In brief, lower-ranking chancery clerks, always looking for sources of income, discovered by 1370 that legal inns could be a source of income. Since chancery clerks were intimately involved with writs and other legal forms, and since the chancery itself had a long-standing training system, these clerks opened their own legal inns to train fledgling lawyers, estate managers, and scriveners. The maps clearly show growth patterns of ownership by the chancery clerks for both legal inns and other London properties in the areas of Holborn and The Strand between 1450 and 1417. However, the maps also show that a royal ordinance of 1417 forbidding chancery clerks to live with lawyers, law students, and other non-chancery personnel had an immediate effect, and properties in that area of London leased by chancery clerks simply stop after 1417. The long-term importance of the patterns shown in the maps is that while the presence of chancery clerks in the legal inns likely created a more coherent education system, their removal forced the legal profession, suddenly without a hostelry managerial class, to professionalize the inns and legal education themselves. Given the number and social status of members of the legal inns, the effect on English education was to free legal education from the limits of chancery clerk education (the clerks were not practicing common lawyers) and to enable it to become broader in theory and practice, in fact, a kind of 'finishing school' for the governing (if not noble) class.

Keywords: GIS, law, London, education

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5065 Quantitative Detection of the Conformational Transitions between Open and Closed Forms of Cytochrome P450 Oxidoreductase (CYPOR) at the Membrane Surface in Different Functional States

Authors: Sara Arafeh, Kovriguine Evguine

Abstract:

Cytochromes P450 are enzymes that require a supply of electrons to catalyze the synthesis of steroid hormones, fatty acids, and prostaglandin hormone. Cytochrome P450 Oxidoreductase (CYPOR), a membrane bound enzyme, provides these electrons in its open conformation. CYPOR has two cytosolic domains (FAD domain and FMN domain) and an N-terminal in the membrane. In its open conformation, electrons flow from NADPH, FAD, and finally to FMN where cytochrome P450 picks up these electrons. In the closed conformation, cytochrome P450 does not bind to the FMN domain to take the electrons. It was found that when the cytosolic domains are isolated, CYPOR could not bind to cytochrome P450. This suggested that the membrane environment is important for CYPOR function. This project takes the initiative to better understand the dynamics of CYPOR in its full length. Here, we determine the distance between specific sites in the FAD and FMN binding domains in CYPOR by Forster Resonance Energy Transfer (FRET) and Ultrafast TA spectroscopy with and without NADPH. The approach to determine these distances will rely on labeling these sites with red and infrared fluorophores. Mimic membrane attachment is done by inserting CYPOR in lipid nanodiscs. By determining the distances between the donor-acceptor sites in these domains, we can observe the open/closed conformations upon reducing CYPOR in the presence and absence of cytochrome P450. Such study is important to better understand CYPOR mechanism of action in various endosomal membranes including hepatic CYPOR which is vital in plasma cholesterol homeostasis. By investigating the conformational cycles of CYPOR, we can synthesize drugs that would be more efficient in affecting the steroid hormonal levels and metabolism of toxins catalyzed by Cytochrome P450.

Keywords: conformational cycle of CYPOR, cytochrome P450, cytochrome P450 oxidoreductase, FAD domain, FMN domain, FRET, Ultrafast TA Spectroscopy

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5064 Validating the Cerebral Palsy Quality of Life for Children (CPQOL-Child) Questionnaire for Use in Sri Lanka

Authors: Shyamani Hettiarachchi, Gopi Kitnasamy

Abstract:

Background: The potentially high level of physical need and dependency experienced by children with cerebral palsy could affect the quality of life (QOL) of the child, the caregiver and his/her family. Poor QOL in children with cerebral palsy is associated with the parent-child relationship, limited opportunities for social participation, limited access to healthcare services, psychological well-being and the child's physical functioning. Given that children experiencing disabilities have little access to remedial support with an inequitable service across districts in Sri Lanka, and given the impact of culture and societal stigma, there may be differing viewpoints across respondents. Objectives: The aim of this study was to evaluate the psychometric properties of the Tamil version of the Cerebral Palsy Quality of Life for Children (CPQOL-Child) Questionnaire. Design: An instrument development and validation study. Methods: Forward and backward translations of the CPQOL-Child were undertaken by a team comprised of a physiotherapist, speech and language therapist and two linguists for the primary caregiver form and the child self-report form. As part of a pilot phase, the Tamil version of the CPQOL was completed by 45 primary caregivers with children with cerebral palsy and 15 children with cerebral palsy (GMFCS level 3-4). In addition, the primary caregivers commented on the process of filling in the questionnaire. The psychometric properties of test-retest reliability, internal consistency and construct validity were undertaken. Results: The test-retest reliability and internal consistency were high. A significant association (p < 0.001) was found between limited motor skills and poor QOL. The Cronbach's alpha for the whole questionnaire was at 0.95.Similarities and divergences were found between the two groups of respondents. The child respondents identified limited motor skills as associated with physical well-being and autonomy. Akin to this, the primary caregivers associated the severity of motor function with limitations of physical well-being and autonomy. The trend observed was that QOL was not related to the level of impairment but connected to environmental factors by the child respondents. In addition to this, the main concern among primary caregivers about the child's future and on the child's lack of independence was not fully captured by the QOL questionnaire employed. Conclusions: Although the initial results of the CPQOL questionnaire show high test-retest reliability and internal consistency of the instrument, it does not fully reflect the socio-cultural realities and primary concerns of the caregivers. The current findings highlight the need to take child and caregiver perceptions of QOL into account in clinical practice and research. It strongly indicates the need for culture-specific measures of QOL.

Keywords: cerebral palsy, CPQOL, culture, quality of life

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5063 TutorBot+: Automatic Programming Assistant with Positive Feedback based on LLMs

Authors: Claudia Martínez-Araneda, Mariella Gutiérrez, Pedro Gómez, Diego Maldonado, Alejandra Segura, Christian Vidal-Castro

Abstract:

The purpose of this document is to showcase the preliminary work in developing an EduChatbot-type tool and measuring the effects of its use aimed at providing effective feedback to students in programming courses. This bot, hereinafter referred to as tutorBot+, was constructed based on chatGPT and is tasked with assisting and delivering timely positive feedback to students in the field of computer science at the Universidad Católica de Concepción. The proposed working method consists of four stages: (1) Immersion in the domain of Large Language Models (LLMs), (2) Development of the tutorBot+ prototype and integration, (3) Experiment design, and (4) Intervention. The first stage involves a literature review on the use of artificial intelligence in education and the evaluation of intelligent tutors, as well as research on types of feedback for learning and the domain of chatGPT. The second stage encompasses the development of tutorBot+, and the final stage involves a quasi-experimental study with students from the Programming and Database labs, where the learning outcome involves the development of computational thinking skills, enabling the use and measurement of the tool's effects. The preliminary results of this work are promising, as a functional chatBot prototype has been developed in both conversational and non-conversational versions integrated into an open-source online judge and programming contest platform system. There is also an exploration of the possibility of generating a custom model based on a pre-trained one tailored to the domain of programming. This includes the integration of the created tool and the design of the experiment to measure its utility.

Keywords: assessment, chatGPT, learning strategies, LLMs, timely feedback

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5062 The Friction and Wear Behaviour of Ti2AlC MAX Phase

Authors: M. Hadji, A. Haddad, Y. Hadji

Abstract:

The effects of boronizing treatment on the friction coefficient and wear behavior of Ti2AlC were investigated. In order to modify the surface properties of Ti2AlC, boronizing treatment was carried out through powder pack cementation in the 1150-1350 °C temperature range. After boronizing treatment, one mixture layer, composed of TiB2 and SiC, forms on the surface of Ti2AlC. The growth of the coating is processed by inward diffusion of Boron and obeys a linear rule. The Boronizing treatment increases the hardness of Ti2AlC from 6 GPa to 13GPa. In the pin-on-disc test, it was found that the material undergoes a steady-state coefficient of friction of around 0.8 and 0.45 in case of Ti2AlC/Al2O3 tribocouple under 7N load for the non treated and the boronized samples, respectively. The wear resistance of Ti2AlC under Al2O3 ball sliding has been significantly improved, which indicated that the boronizing treatment is a promising surface modification way of Ti2AlC.

Keywords: MAX phase, wear, hardness, boronizing

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5061 Definition of Quality Indicators for Damascus Rose Oil (Rosa damascena) Flora of Morocco

Authors: Serebryanaya Fatima, Essaih Hind

Abstract:

The Rosa damascena (Rosa damascena Mill.) is an interesting medicinal plant; it is famous in different countries and has medicinal use in many cultures. The main groups of pharmacological actions of rose oil are connected with anti-inflammatory, antifungal activity, also antioxidant and antibacterial, and antiparasitic properties. We have prepared the quality indicators analysis of the Damascus rose oil. An iodine number, acid number, and oil peroxide number were determined. The following indicators of the quality of rose oil have been studied. The determination was carried out according to the pharmacopoeic methods of analysis of essential oils, the definition of peroxide number (1,971%), iodine number (3,365%), and acid number (0,0526%).

Keywords: Rosa damascene, Rosa damascena Mill., iodine number, acid number, oil peroxide number

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5060 Investigating The Effects of Utilizing Different Curing Agents on High-Performance Concrete

Authors: Mostafa M. Ahmed, Kotaro Nose, Takashi Fujii, Toshiki Ayano

Abstract:

The Study shed the light on the effects of employing varied curing agents (No.1-No.6): bleeding water, and sprinkling water, aqueous basic silica compound, modified acrylic resin, the emulsion of solid wax and nonionic surfactant, and water-based paraffin wax, on the properties of high-performance concrete (HPC) in comparison with the cured specimens according to the standard curing at 20 ± 3°C (JIS A 0203:2019). The specimens cured in accordance with standard curing exhibit a better compressive strength and higher freeze-thaw resistance compared to most non-standard-cured samples.

Keywords: curing agents, high-performance concrete, compressive strength, cumulative scaling, freeze-thaw resistance

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5059 Effect of Natural Binder on Pang-Rum Hardness

Authors: Pattaranut Eakwaropas, Khemjira Jarmkom, Warachate Khobjai, Surachai Techaoei

Abstract:

The aim of this study is to improve Pang-Rum (PR) hardness by adding natural binders. PR is one of Thai tradition aroma products. In the past, it was used for aesthetic propose on face and body with good odor. Nowadays, PR is not popular and going to be disappeared. Five natural materials, i.e. agar, rice flour, glutinous flour, corn starch, and tapioca starch were selected to use as binders. Binders were dissolved with boiled water into concentration 5% and 10% w/w except agar that was prepared 0.5% and 1% w/w. PR with and without binder were formulated. Physical properties, i.e. weight, shape, color, and hardness were evaluated. PR with 10% of corn starch solution had suitable hardness (14.2±0.9 kg) and the best appearance. In the future, it would be planned to study about odor and physical stability for decorated product development.

Keywords: aromatic water, hardness, natural binder, pang-rum

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5058 Second Language Development with an Intercultural Approach: A Pilot Program Applied to Higher Education Students from a Escuela Normal in Atequiza, Mexico

Authors: Frida C. Jaime Franco, C. Paulina Navarro Núñez, R. Jacob Sánchez Nájera

Abstract:

The importance of developing multi-language abilities in our global society is noteworthy. However, the necessity, interest, and consciousness of the significance that the development of another language represents, apart from the mother tongue, is not always the same in all contexts as it is in multicultural communities, especially in rural higher education institutions immersed in small communities. Leading opportunities for digital interaction among learners from Mexico and abroad partners represents scaffolding towards, not only language skills development but also intercultural communicative competences (ICC). This study leads us to consider what should be the best approach to work while applying a program of ICC integrated into the practice of EFL. While analyzing the roots of the language, it is possible to obtain the main objective of learning another language, to communicate with a functional purpose, as well as attaching social practices to the learning process, giving a result of functionality and significance to the target language. Hence, the collateral impact that collaborative learning leads to, aims to contribute to a better global understanding as well as a means of self and other cultural awareness through intercultural communication. While communicating through the target language by online collaboration among students in platforms of long-distance communication, language is used as a tool of interaction to broaden students’ perspectives reaching a substantial improvement with the help of their differences. This process should consider the application of the target language in the inquiry of sociocultural information, expecting the learners to integrate communicative skills to handle cultural differentiation at the same time they apply the knowledge of their target language in a real scenario of communication, despite being through virtual resources.

Keywords: collaborative learning, communicative approach, culture, interaction, interculturalism, target language, virtual partnership

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5057 Effect of Synthesis Method on Structural, Morphological Properties of Zr0.8Y0.2-xLax Oxides (x=0, 0.1, 0.2)

Authors: Abdelaziz Ghrib, Samir Hattali, Mouloud Ghrib, Mohamed Lamine Aouissia, David Ruch

Abstract:

In the present study, the solid solutions with a chemical composition of Zr0.8Y0.2-xLaxO2 (x=0, 0.1, 0.2) were synthesized via two routes, by hydrothermal method using NaOH as precipitating agent at 230°C for 15h and by the sol–gel process using citric acid as complexing agent. Compounds have been characterized by powder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Thermo gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) techniques for appropriate characterization of the distinct thermal events occurring during synthesis. All the compounds crystallize in cubic fluorite structure, as indicated by X-ray diffraction studie. The microstructure of oxides synthesized by sol-gel showed porosity that increased with the lanthanum La3+ contents compared to hydrothermal method which gives a single crystal oxide.

Keywords: oxide, hydrothermal, rare earth, solubility, sol-gel, ternary mixture

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5056 Physicochemical Properties of Moringa oleifera Seeds

Authors: Oyewusi Peter Ayodele, Onipede Ayodeji

Abstract:

Our research focuses on some physicochemical parameters of Moringa Oleifera seed meal and its seed oil to determine its nutritional quality. Proximate, mineral, and vitamin analyses were performed on the defatted seed meal, while fatty acid determination was carried out on the seed oil. The results of the proximate composition show moisture content (3.52 ± 0.01), ash (2.80 ± 0.33), crude fibre (3.92 ± 0.01), protein (42.96 ± 0.05), crude fat (7.04 ± 0.01) and carbohydrate (36.79 ± 0.04). The mineral composition shows that the seed is rich in Ca, K, and Na with 220ppm, 205ppm, and 118ppm, respectively. The seed has vitamins A and C with 2.17 ± 0.01mg/100g and 6.95 ± 0.00 mg/100g respectively. The seed also contains 56.62 %, 38.50 %, and 5.24 % saturated, monounsaturated, and polyunsaturated fatty acids, respectively. It could be illustrated that Moringa seeds and their oil can be considered potential sources for both dietary and industrial purposes.

Keywords: Moringa oleifera seed, chemical composition, fatty acid, proximate, minerals and vitamins compositions

Procedia PDF Downloads 281
5055 Performance Evaluation and Kinetics of Artocarpus heterophyllus Seed for the Purification of Paint Industrial Wastewater by Coagulation-Flocculation Process

Authors: Ifeoma Maryjane Iloamaeke, Kelvin Obazie, Mmesoma Offornze, Chiamaka Marysilvia Ifeaghalu, Cecilia Aduaka, Ugomma Chibuzo Onyeije, Claudine Ifunanaya Ogu, Ngozi Anastesia Okonkwo

Abstract:

This work investigated the effects of pH, settling time, and coagulant dosages on the removal of color, turbidity, and heavy metals from paint industrial wastewater using the seed of Artocarpus heterophyllus (AH) by the coagulation-flocculation process. The paint effluent was physicochemically characterized, while AH coagulant was instrumentally characterized by Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), and X-ray diffraction (XRD). A Jar test experiment was used for the coagulation-flocculation process. The result showed that paint effluent was polluted with color, turbidity (36000 NTU), mercury (1.392 mg/L), lead (0.252 mg/L), arsenic (1.236 mg/L), TSS (63.40mg/L), and COD (121.70 mg/L). The maximum color removal efficiency was 94.33% at the dosage of 0.2 g/L, pH 2 at a constant time of 50 mins, and 74.67% at constant pH 2, coagulant dosage of 0.2 g/L and 50 mins. The highest turbidity removal efficiency was 99.94% at 0.2 g/L and 50 mins at constant pH 2 and 96.66% at pH 2 and 0.2 g/L at constant time of 50 mins. The mercury removal efficiency of 99.29% was achieved at the optimal condition of 0.8 g/L coagulant dosage, pH 8, and constant time of 50 mins and 99.57% at coagulant dosage of 0.8 g/L, time of 50 mins constant pH 8. The highest lead removal efficiency was 99.76% at a coagulant dosage of 10 g/L, time of 40 mins at constant pH 10, and 96.53% at pH 10, coagulant dosage of 10 g/L and constant time of 40 mins. For arsenic, the removal efficiency is 75.24 % at 0.8 g/L coagulant dosage, time of 40 mins, and constant pH of 8. XRD imaging before treatment showed that Artocarpus heterophyllus coagulant was crystalline and changed to amorphous after treatment. The SEM and FTIR results of the AH coagulant and sludge suggested there were changes in the surface morphology and functional groups before and after treatment. The reaction kinetics were modeled best in the second order.

Keywords: Artocarpus heterophyllus, coagulation-flocculation, coagulant dosages, setting time, paint effluent

Procedia PDF Downloads 89
5054 Peat Soil Stabilization Methods: A Review

Authors: Mohammad Saberian, Mohammad Ali Rahgozar, Reza Porhoseini

Abstract:

Peat soil is formed naturally through the accumulation of organic matter under water and it consists of more than 75% organic substances. Peat is considered to be in the category of problematic soil, which is not suitable for construction, due to its high compressibility, high moisture content, low shear strength, and low bearing capacity. Since this kind of soil is generally found in many countries and different regions, finding desirable techniques for stabilization of peat is absolutely essential. The purpose of this paper is to review the various techniques applied for stabilizing peat soil and discuss outcomes of its improved mechanical parameters and strength properties. Recognizing characterization of stabilized peat is one of the most significant factors for architectural structures; as a consequence, various strategies for stabilization of this susceptible soil have been examined based on the depth of peat deposit.

Keywords: peat soil, stabilization, depth, strength, unconfined compressive strength (USC)

Procedia PDF Downloads 566
5053 The Role of Universities in Saudi Arabia in Environmental Awareness

Authors: Hamad Albadr

Abstract:

With the growth that has occurred in the orientation of universities from liability cognitive and maintain the culture of the community to liability functional creating graduates to work according to the needs of the community development; representing the university in today's world, the prime mover of the wheel of development in the community and find appropriate solutions to the problems they are facing and adapt to the demands of the changing environment. This paper deals with the role of Saudi universities as institutions, government agencies, non-governmental organizations and the extent of its responsibility to the environmental awareness of the community members in various segments, where it will use the research methodology descriptive and analytical, to gather information, data and analysis answers the study sample consisting of 1500 people from the staff of the Saudi universities: The members of the faculty, and members of the administrative and technical bodies, and current students, 500 of them are responsible for employment in the labor sector and graduates. Where will review the paper to identify the extent to which the objectives of the academic programs in Saudi universities to the needs of the community, and the extent to which the course content submitted to the characteristics of the local environment for the community and how he benefited them to ensure its conformity with the changing needs of society, and how to address the research presented in academic programs to the needs of society and its problems , and the extent to which graduate students to deal enough of social responsibility and commitment to community service and the preservation of the environment, and the availability of a clear policy to serve the community with the academic programs, and how to encourage faculty, staff and students to participate in community service. And the availability of counseling services for school students for vocational guidance, scientific, environmental, and the contribution of Academic Programs publishes scientific and technical culture and the environmental community members.

Keywords: universities in Saudi Arabia, environmental awareness, academic programs, environmental community

Procedia PDF Downloads 311
5052 A Pull-Out Fiber/Matrix Interface Characterization of Vegetal Fibers Reinforced Thermoplastic Polymer Composites, the Influence of the Processing Temperature

Authors: Duy Cuong Nguyen, Ali Makke, Guillaume Montay

Abstract:

This work presents an improved single fiber pull-out test for fiber/matrix interface characterization. This test has been used to study the Inter-Facial Shear Strength ‘IFSS’ of hemp fibers reinforced polypropylene (PP). For this aim, the fiber diameter has been carefully measured using a tomography inspired method. The fiber section contour can then be approximated by a circle or a polygon. The results show that the IFSS is overestimated if the circular approximation is used. The Influence of the molding temperature on the IFSS has also been studied. We find a molding temperature of 183°C leads to better interface properties. Above or below this temperature the interface strength is reduced.

Keywords: composite, hemp, interface, pull-out, processing, polypropylene, temperature

Procedia PDF Downloads 386
5051 Adding a Degree of Freedom to Opinion Dynamics Models

Authors: Dino Carpentras, Alejandro Dinkelberg, Michael Quayle

Abstract:

Within agent-based modeling, opinion dynamics is the field that focuses on modeling people's opinions. In this prolific field, most of the literature is dedicated to the exploration of the two 'degrees of freedom' and how they impact the model’s properties (e.g., the average final opinion, the number of final clusters, etc.). These degrees of freedom are (1) the interaction rule, which determines how agents update their own opinion, and (2) the network topology, which defines the possible interaction among agents. In this work, we show that the third degree of freedom exists. This can be used to change a model's output up to 100% of its initial value or to transform two models (both from the literature) into each other. Since opinion dynamics models are representations of the real world, it is fundamental to understand how people’s opinions can be measured. Even for abstract models (i.e., not intended for the fitting of real-world data), it is important to understand if the way of numerically representing opinions is unique; and, if this is not the case, how the model dynamics would change by using different representations. The process of measuring opinions is non-trivial as it requires transforming real-world opinion (e.g., supporting most of the liberal ideals) to a number. Such a process is usually not discussed in opinion dynamics literature, but it has been intensively studied in a subfield of psychology called psychometrics. In psychometrics, opinion scales can be converted into each other, similarly to how meters can be converted to feet. Indeed, psychometrics routinely uses both linear and non-linear transformations of opinion scales. Here, we analyze how this transformation affects opinion dynamics models. We analyze this effect by using mathematical modeling and then validating our analysis with agent-based simulations. Firstly, we study the case of perfect scales. In this way, we show that scale transformations affect the model’s dynamics up to a qualitative level. This means that if two researchers use the same opinion dynamics model and even the same dataset, they could make totally different predictions just because they followed different renormalization processes. A similar situation appears if two different scales are used to measure opinions even on the same population. This effect may be as strong as providing an uncertainty of 100% on the simulation’s output (i.e., all results are possible). Still, by using perfect scales, we show that scales transformations can be used to perfectly transform one model to another. We test this using two models from the standard literature. Finally, we test the effect of scale transformation in the case of finite precision using a 7-points Likert scale. In this way, we show how a relatively small-scale transformation introduces both changes at the qualitative level (i.e., the most shared opinion at the end of the simulation) and in the number of opinion clusters. Thus, scale transformation appears to be a third degree of freedom of opinion dynamics models. This result deeply impacts both theoretical research on models' properties and on the application of models on real-world data.

Keywords: degrees of freedom, empirical validation, opinion scale, opinion dynamics

Procedia PDF Downloads 118
5050 Psychological Alarm among Individuals Suffering from Irritable Bowel Syndrome

Authors: Selim A., Albasher N., Bakrmom G., Alanzi S.

Abstract:

Irritable bowel syndrome (IBS) is a chronic functional bowel disorder characterized by abdominal discomfort or pain and associated with alteration in frequency and/or form of bowel habit among other symptoms. This diagnosis is associated with increased levels of psychological distress, maladaptive coping, genetic risk factors, abnormal small and colonic intestine transit, change in stool frequency or form and abdominal discomfort or pain. Aim: The aim of the study was to assess psychological alarm among individuals suffering from Irritable Bowel Syndrome (IBS). Methods: A cross-sectional correlational research design was used to conduct the current study. A convenience sample of 504 participants was included in the present study. Data were collected using a self-report questionnaire. The questionnaire included socio-demographic data, ROME III to identify Irritable Bowel Syndrome (IBS) and Psychological Alarm Questionnaire. Results: Out of 504 participants who reported abdominal discomfort, 297 (58.9 %) participants met the diagnostic criteria of IBS. The mean age of the IBS participants was 30.16 years, females composed 75.1% of the IBS participants, and 55.2% did not seek medical help. Psychological alarms such as feeling anxious, feeling depressed, having suicidal ideations, bodily pain, having impaired functioning due to pain and feeling unable to cope with pain were significantly high among IBS individuals when compared to individuals not suffering from IBS. Psychological alarms such as feeling anxious, feeling depressed, having suicidal ideations, bodily pain, having impaired functioning due to pain and feeling unable to cope with pain were significantly high among IBS individuals compared to individuals not suffering from IBS. Conclusion: IBS is highly associated with significant psychological alarms including depression, anxiety and suicidal ideas.

Keywords: abdominal pain , irritable bowel syndrome, distress, psychological alarms

Procedia PDF Downloads 184
5049 Time Delay Estimation Using Signal Envelopes for Synchronisation of Recordings

Authors: Sergei Aleinik, Mikhail Stolbov

Abstract:

In this work, a method of time delay estimation for dual-channel acoustic signals (speech, music, etc.) recorded under reverberant conditions is investigated. Standard methods based on cross-correlation of the signals show poor results in cases involving strong reverberation, large distances between microphones and asynchronous recordings. Under similar conditions, a method based on cross-correlation of temporal envelopes of the signals delivers a delay estimation of acceptable quality. This method and its properties are described and investigated in detail, including its limits of applicability. The method’s optimal parameter estimation and a comparison with other known methods of time delay estimation are also provided.

Keywords: cross-correlation, delay estimation, signal envelope, signal processing

Procedia PDF Downloads 474
5048 Ab Initio Multiscale Catalytic Synthesis/Cracking Reaction Modelling of Ammonia as Liquid Hydrogen Carrier

Authors: Blaž Likozar, Andraž Pavlišič, Matic Pavlin, Taja Žibert, Aleksandra Zamljen, Sašo Gyergyek, Matej Huš

Abstract:

Ammonia is gaining recognition as a carbon-free fuel for energy-intensive applications, particularly transportation, industry, and power generation. Due to its physical properties, high energy density of 3 kWh kg-1, and high gravimetric hydrogen capacity of 17.6 wt%, ammonia is an efficient energy vector for green hydrogen, capable of mitigating hydrogen’s storage, distribution, and infrastructure deployment limitations. Chemicalstorage in the form of ammonia provides an efficient and affordable solution for energy storage, which is currently a critical step in overcoming the intermittency of abundant renewable energy sources with minimal or no environmental impact. Experiments were carried out to validate the modelling in a packed bed reactor, which proved to be agreeing.

Keywords: hydrogen, ammonia, catalysis, modelling, kinetics

Procedia PDF Downloads 65
5047 Vibration of Nonhomogeneous Timoshenko Nanobeam Resting on Winkler-Pasternak Foundation

Authors: Somnath Karmakar, S. Chakraverty

Abstract:

This work investigates the vibration of nonhomogeneous Timoshenko nanobeam resting on the Winkler-Pasternak foundation. Eringen’s nonlocal theory has been used to investigate small-scale effects. The Differential Quadrature method is used to obtain the frequency parameters with various classical boundary conditions. The nonhomogeneous beam model has been considered, where Young’s modulus and density of the beam material vary linearly and quadratically. Convergence of frequency parameters is also discussed. The influence of mechanical properties and scaling parameters on vibration frequencies are investigated for different boundary conditions.

Keywords: Timoshenko beam, Eringen's nonlocal theory, differential quadrature method, nonhomogeneous nanobeam

Procedia PDF Downloads 112