Search results for: instrumented composite material

Authors: Eliska Oberhofnerova, Milos Panek, Stepan Hysek, Martin Lexa

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Nowadays the use of wood, both indoors and outdoors, is constantly increasing. However wood is a natural organic material and in the exterior is subjected to a degradation process caused by abiotic factors (solar radiation, rain, moisture, wind, dust etc.). This process affects only surface layers of wood but neglecting some of the basic rules of wood protection leads to increased possibility of biological agents attack and thereby influences a function of the wood element. The process of wood degradation can be decreased by proper surface treatment, especially in the case of less naturally durable wood species, as spruce. Modern coating systems are subjected to many requirements such as colour stability, hydrophobicity, low volatile organic compound (VOC) content, long service life or easy maintenance. The aim of this study is to evaluate the colour stability of spruce wood (Picea abies), as the basic parameter indicating the coating durability, treated with two layers of transparent natural oil wood stain and exposed to outdoor conditions. The test specimens were exposed for 2 years to natural weathering and 2000 hours to artificial weathering in UV-chamber. The colour parameters were measured before and during exposure to weathering by the spectrophotometer according to CIELab colour space. The comparison between untreated and treated wood and both testing procedures was carried out. The results showed a significant effect of coating on the colour stability of wood, as expected. Nevertheless, increasing colour changes of wood observed during the exposure to weathering differed according to applied testing procedure - natural and artificial.

Keywords: colour stability, natural and artificial weathering, spruce wood, transparent coating

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Authors: Hari Krishna Ayyappa, Reenu Singh

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Rising population and restricted land for development has led towards the growth of vertical buildings and small complexes. It provides many possibilities to change the shape and size of internal space in addition to the social impacts on the commercial spaces. With the increased volatility of necessities of people, the need for mental and physical comfort has continuously increased. . Living in a small space musts minimalist and space- saving cabinetwork results to sustain mortal good. This paper attempts to explore the Influence of Using Minimalist Furniture on the Efficiency of the commercial Space interiors by means of the variable resulting from preceding studies based on literature. A literature review was conducted on research articles to understand the contributing variables in a well designed small commercial spaces. A questionnaire survey was conducted to understand the layout of small commercial spaces with respect to Environmental impact, material, Design elements, Modern approach, Layered lightings, and colours. The problem of small spaces can be resolved by some ways; it's still needed for cabinetwork to develop to be more innovative to accommodate small living spaces. Since cabinetwork is a necessity and not luxury, everybody is in need of it. The spatial factors affecting overall satisfaction at a detailed position were bandied. The variable helped in proposing design ideation and mock ups to explore improved interiors. This paper concludes that most of the principles of the minimalist approach have been overlooked at, which had an impact on the space efficiency in commercial spaces like storage rooms, office area, retail stores, restaurants, and other spaces where business is conducted.

Keywords: materials, modern approach, space efficiency, tall commercial buildings

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Authors: Hong Zhang

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The main purpose of this study is to show that machine translation (MT) post-editing (PE) training can help our Chinese students learn Spanish as a second language. Our hypothesis is that they might make better use of it by learning PE skills specific for foreign language learning. We have developed PE training materials based on the data collected in a previous study. Training material included the special error types of the output of MT and the error types that our Chinese students studying Spanish could not detect in the experiment last year. This year we performed a pilot study in order to evaluate the PE training materials effectiveness and to what extent PE training helps Chinese students who study the Spanish language. We used screen recording to record these moments and made note of every action done by the students. Participants were speakers of Chinese with intermediate knowledge of Spanish. They were divided into two groups: Group A performed PE training and Group B did not. We prepared a Chinese text for both groups, and participants translated it by themselves (human translation), and then used Google Translate to translate the text and asked them to post-edit the raw MT output. Comparing the results of PE test, Group A could identify and correct the errors faster than Group B students, Group A did especially better in omission, word order, part of speech, terminology, mistranslation, official names, and formal register. From the results of this study, we can see that PE training can help Chinese students learn Spanish as a second language. In the future, we could focus on the students’ struggles during their Spanish studies and complete the PE training materials to teach Chinese students learning Spanish with machine translation.

Keywords: machine translation, post-editing, post-editing training, Chinese, Spanish, foreign language learning

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Authors: Richard Briginshaw, Hana Alaojeli, Javaria Ahmad, Hamza Gaffar, Nourtan Murad

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Sustainable renovations to cultural buildings and sites require a high level of competency in the sometimes conflicting areas of social/historical demands, environmental concerns, and the programmatic and technical requirements of the project. A detailed analysis of the existing site, building and client program are critical to reveal both challenges and opportunities. This forms the starting point for the design process – empirical explorations that search for a balanced and inspired architectural solution to the project. The Red Bay National Historic Site on the Labrador Coast of eastern Canada is a challenging project to explore and resolve these ideas. Originally the site of a 16ᵗʰ century whaling station occupied by Basque sailors from France and Spain, visitors now experience this history at the interpretive center, along with the unique geography, climate, local culture and vernacular architecture of the area. Working with our client, Parks Canada, the project called for significant alterations and expansion to the existing facility due to an increase in the number of annual visitors. Sustainable aspects of the design are focused on sensitive site development, passive energy strategies such as building orientation and building envelope efficiency, active renewable energy systems, carefully considered material selections, water efficiency, and interiors that respond to human comfort and a unique visitor experience.

Keywords: sustainability, renovations and expansion, cultural project, architectural design, green building

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Authors: Yamkela Zitwana

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Soil erosion along the roads and/or road riparian areas has become a norm in the Eastern Cape. Soil erosion refers to the detachment and transportation of soil from one area (onsite) to another (offsite). This displacement or removal of soil can be caused by water, air and sometimes gravity. This will focus on accelerated soil erosion which is the result of human interference with the environment. Engcobo local municipality falls within the Eastern Cape Province in the eastern side of CHRIS HANI District municipality. The focus road is R61 protruding from the Engcobo town outskirts along the Nyanga SSS on the way to Umtata although it will cover few Kilometers away from Engcobo. This research aims at looking at the contribution made by road construction to soil erosion. Steps to achieve the result will involve revisiting the phases of road construction through unstructured interviews, identifying the types of soil erosion evident in the area by doing a checklist, checking the material, utensils and equipment used for road construction and the contribution of road construction through stratified random sampling checking the soil color and texture. This research will use a pragmatic approach which combines related methods and consider the flaws of each method so as to ensure validity, precision and accuracy. Both qualitative and quantitative methods will be used. Statistical methods and GIS analysis will be used to analyze the collected data.

Keywords: soil erosion, road riparian, accelerated soil erosion, road construction, sampling, universal soil loss model, GIS analysis, focus groups, qualitative, quantitative method, research, checklist questionnaires, unstructured interviews, pragmatic approach

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Authors: John Lloyd Angolluan, Jennile Caday, Crystal Mae Estrella, Reike Alliyah Taladua, Zion Michael Ysulat

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One of the requirements of having the ability to communicate in English is by having adequate vocabulary. Nowadays, people are more engaged in watching movie streams on which they can watch movies in a very portable way, such as Netflix. Wherein Netflix became global demand for online media has taken off in recent years. This research aims to know whether the use of bimodal subtitles on Netflix English movies can enhance vocabulary. This study is quantitative and utilizes a descriptive method, and this study aims to explore the use of bimodal subtitles on Netflix English movies to enhance the vocabulary of students. The respondents of the study were the selected Second-year English majors of Rizal Technological University Pasig and Boni Campus using the purposive sampling technique. The researcher conducted a survey questionnaire through the use of Google Forms. In this study, the weighted mean was used to evaluate the student's responses to the statement of the problems of the study of the use of bimodal subtitles on Netflix English movies. The findings of this study revealed that the bimodal subtitle on Netflix English movies enhanced students’ vocabulary learning acquisition by providing learners with access to large amounts of real and comprehensible language input, whether accidentally or intentionally, and it turns out that bimodal subtitles on Netflix English movies help students recognize vocabulary, which has a positive impact on their vocabulary building. Therefore, the researchers advocate that watching English Netflix movies enhances students' vocabulary by using bimodal subtitled movie material during their language learning process, which may increase their motivation and the usage of bimodal subtitles in learning new vocabulary. Bimodal subtitles need to be incorporated into educational film activities to provide students with a vast amount of input to expand their vocabulary.

Keywords: bimodal subtitles, Netflix, English movies, vocabulary, subtitle, language, media

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Authors: Rafał Kamiński, Joel Rech, Philippe Bertrand, Christophe Desrayaud

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Additive manufacturing is a hot topic for industry. Among the additive techniques, Selective Laser Melting (SLM) becomes even more popular, especially for making parts for aerospace applications, thanks to its design freedom (customized and light structures) and its reduced time to market. However, some functional surfaces have to be machined to achieve small tolerances and low surface roughness to fulfill industry specifications. The complex shapes designed for SLM (ex: titanium turbine blades) necessitate the use of ball end milling operations like in the conventional process after forging. However, the metallurgical state of TA6V is very different from the one obtained usually from forging, because of the laser sintering layer by layer. So this paper aims to investigate the influence of new TA6V metallurgies produced by SLM on the machinability in ball end milling. Machinability is considered as the property of a material to obtain easily and by a cheap way a functional surface. This means, for instance, the property to limit cutting tool wear rate and to get smooth surfaces. So as to reach this objective, SLM parts have been produced and heat treated with various conditions leading to various metallurgies that are compared with a standard equiaxed α+β wrought microstructure. The machinability is analyzed by measuring surface roughness, tool wear and cutting forces for a range of cutting conditions (depth of cut 'ap', feed per tooth 'fz', spindle speed 'N') in accordance with industrial practices. This work has revealed that TA6V produced by SLM can lead to a better machinability that standard wrought alloys.

Keywords: ball milling, selective laser melting, surface roughness, titanium, wear

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Authors: Ekere E. Kokonne, Isimi C. Yetunde, Okoh E. Judith, Okafor E. Ijeoma, Ajeh J. Isaac, Olobayo O. Kunle, Emeje O. Martins

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NIPRIMAL® is a mono herbal formulation of Nauclea latifolia used in the treatment of malaria. The stability of extracts made from plant material is essential to ensure the quality, safety and efficacy of the finished product. This study assessed the stability of the formulation under three different storage conditions; normal room temperature, infrared and under refrigeration. Differential Scanning Calorimetry (DSC) and Thin Layer Chromatography (TLC) were used to monitor the formulations. The DSC analysis was done from 0oC to 350oC under the three storage conditions. Results obtained indicate that NIPRIMAL® was stable at all the storage conditions investigated. Thin layer chromatography (TLC) after 6 months showed there was no significant difference between retention factor (RF) values for the various storage conditions. The reference sample had four spots with RF values of 0.47, 0.68, 0.76, 0.82 respectively and these spots were retained in the test formulations with corresponding RF values were after 6 months at room temperature and refrigerated temperature been 0.56, 0.73, 0.80, 0.92 and 0.47, 0.68, 0.76, 0.82 respectively. On the other hand, the RF values (0.55, 0.74, 0.77, 0.93) obtained under infrared after 1 month varied slightly from the reference. The sample exposed to infrared had a lower heat capacity compared to that stored under room temperature or refrigeration. A combination of TLC and DSC measurements has been applied for assessing the stability of NIPRIMAL®. Both methods were found to be rapid, sensitive and reliable in determining its stability. It is concluded that NIPRIMAL® can be stored under any of the tested conditions without degradation. This study is a major contribution towards developing appropriate stability monitoring parameters for herbal products.

Keywords: differential scanning calorimetry, formulation, NIPRIMAL®, stability, thin layer hromatography

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Authors: Qi Wang

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In the classroom, teachers have been trained to complete the target task within the limited lecture time, meanwhile learners need to receive a lot of new knowledge, however, most of the time the learners come without the proper pre-class preparation to efficiently take in the contents taught in class. Under this circumstance, teachers do have no time to check whether the learners fully understand the content or not, how the learners communicate in the different contexts, until teachers see the results when the learners are tested. In the past decade, the teaching of Chinese has taken a trend. Teaching focuses less on the use of proper grammatical terms/punctuation and is now placing a heavier focus on the materials from real life contexts. As a result, it has become a greater challenge to teachers, as this requires teachers to fully understand/prepare what they teach and explain the content with simple and understandable words to learners. On the other hand, the same challenge also applies to the learners, who come from different countries. As they have to use what they learnt, based on their personal understanding of the material to effectively communicate with others in the classroom, even in the contexts of a day to day communication. To reach this win-win stage, Feynman’s Technique plays a very important role. This practical report presents you how the Feynman’s Technique is applied into Chinese courses, both writing & oral, to motivate the learners to practice more on writing, reading and speaking in the past few years. Part 1, analysis of different teaching styles and different types of learners, to find the most efficient way to both teachers and learners. Part 2, based on the theory of Feynman’s Technique, how to let learners build the knowledge from knowing the name of something to knowing something, via different designed target tasks. Part 3. The outcomes show that Feynman’s Technique is the interaction of learning style and teaching style, the double-edged sword of Teaching & Learning Chinese as a Second Language.

Keywords: Chinese, Feynman’s technique, learners, teachers

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Authors: L. Sasikala, Bhaarathi Dhurai

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Increase in antibiotic resistance bacteria leads to the development of active wound dressings, which absorb any bodily fluid, evaporation of moisture at a certain rate and can be easily removed after healing. Natural materials like chitosan, herbs, and honey have number of active materials present in them to accelerate wound healing and to arrest wound in infections. Hence with the advantages of biomaterials, a film was prepared using chitosan and honey. There are a lot of practical considerations with respect to honey. Honey exerts many beneficial actions on the wound surface only when it remains. The attempts to hold honey on the surface of the wound remain a question because honey becomes a very runny liquid when it comes to body temperature. Hence, this research was focused on development of a new form of wound dressing, by holding honey on the wound surface in different form and also which has a combined effect of manuka (Leptospermum scoparium) honey and chitosan. Chitosan-honey film was prepared using casting technique. Films were prepared in different variations; with acetic acid and with lactic acid; with and without honey. In summary, the film produced from 2% chitosan- 1% lactic acid as a solvent, with 10% honey shows optimum inclined values in all the tests, like thickness, folding endurance, weight, water vapor transmission, tensile strength, swelling ratio and antimicrobial activity, with specific reference to wound dressings. The film has water vapor transmission of 1680 g/m²/day, water absorption of 225%, tensile strength of 39.1N/mm² and elongation of 50.3%. There is a notable inhibition zone of 29 mm against S. aureus and 24 mm against E. coli in the case of chitosan-lactic acid-honey film. The film also arrests, microbes transmitting from the outside environment to wound bed, which can be used as an effective wound dressing material.

Keywords: casting technique, chitosan, honey, film, wound dressings

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Authors: Rowena Clemino Alcoba

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Thailand is host to the largest number of refugees in the region. The country has been one of the most accessible points of entry to refugees around the world because it has relatively lenient visa requirements, enabling asylum seekers to enter the country and subsequently search for legal assistance. However, because Thailand is not a signatory to the 1951 Geneva Convention on Refugees which governs the refugee status determination and safeguards several rights of the refugees, there are no national laws or administrative framework on the protection of refugees. Refugees are considered as illegal migrants, and certain groups are permitted to stay temporarily only upon executive discretion. Aside from the documented group of refugees from the Myanmar border, there are many others who came from different parts of the world. They are known as urban refugees believed to be in the thousands and are scattered in the impoverished areas of Bangkok and the suburbs. This study aims to advance understanding of the role of civil society organizations in supporting refugees, with particular focus on urban refugees. Using the method of triangulation in qualitative research, the study investigates the life journey of a refugee family from Pakistan, their difficulties and struggles to survive in perilous situations. The study presents the dynamics of how civil society works and collaborates to fill the gap for much-needed social services. It also discusses the depth and scope of the role of faith actors in the protection and support of this vulnerable sector. The engagement of civil society reveals framework and structure that aims to create long-term impact. The help provided is not merely monetary or material dole-outs but a platform for refugees to integrate with community, develop skills and make productive use of their time.

Keywords: asylum seeker, civil society, faith actors, refugees

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Authors: Hossein Askarinejad, Manicka Dhanasekar

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In railway tracks, two adjacent rails are either welded or connected using bolted jointbars. In recent years the number of bolted rail joints is reduced by introduction of longer rail sections and by welding the rails at location of some joints. However, significant number of bolted rail joints remains in railways around the world as they are required to allow for rail thermal expansion or to provide electrical insulation in some sections of track. Regardless of the quality and integrity of the jointbar and bolt connections, the bending stiffness of jointbars is much lower than the rail generating large deflections under the train wheels. In addition, the gap or surface discontinuity on the rail running surface leads to generation of high wheel-rail impact force at the joint gap. These fundamental weaknesses have caused high rate of failure in track components at location of rail joints resulting in significant economic and safety issues in railways. The mechanical behavior of railway track at location of joints has not been fully understood due to various structural and material complexities. Although there have been some improvements in the methods for analysis of track at jointed rails in recent years, there are still uncertainties concerning the accuracy and reliability of the current methods. In this paper the current methods in analysis of track with a rail joint are critically evaluated and the new advances and recent research outcomes in this area are discussed. This research is part of a large granted project on rail joints which was defined by Cooperative Research Centre (CRC) for Rail Innovation with supports from Australian Rail Track Corporation (ARTC) and Queensland Rail (QR).

Keywords: jointed rails, railway mechanics, track dynamics, wheel-rail interaction

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Authors: G. Singh, H.Schuster, U. Füssel

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The stability of electric arc and durability of electrode tip used in Tungsten Inert Gas (TIG) welding demand a metallurgical study about the chemical transport mechanism of emitter oxide particles in tungsten electrode during its real welding conditions. The tungsten electrodes doped with emitter oxides of rare earth oxides such as La₂O₃, Th₂O₃, Y₂O₃, CeO₂ and ZrO₂ feature a comparatively lower work function than tungsten and thus have superior emission characteristics due to lesser surface temperature of the cathode. The local change in concentration of these emitter particles in tungsten electrode due to high temperature diffusion (chemical transport) can change its functional properties like electrode temperature, work function, electron emission, and stability of the electrode tip shape. The resulting increment in tip surface temperature results in the electrode material loss. It was also observed that the tungsten recrystallizes to large grains at high temperature. When the shape of grain boundaries are granular in shape, the intergranular diffusion of oxide emitter particles takes more time to reach the electrode surface. In the experimental work, the microstructure of the used electrode's tip surface will be studied by scanning electron microscope and reflective X-ray technique in order to gauge the extent of the diffusion and chemical reaction of emitter particles. Besides, a simulated model is proposed to explain the effect of oxide particles diffusion on the electrode’s microstructure, electron emission characteristics, and electrode tip erosion. This model suggests metallurgical modifications in tungsten electrode to enhance its erosion resistance.

Keywords: rare-earth emitter particles, temperature-dependent diffusion, TIG welding, Tungsten electrode

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Authors: Nurtati Soewarno, Dian Duhita

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The existence of civilization from the past is recognized by the left objects such as monuments, buildings or even a town. The relics were designed and made well, using the good quality material so it could persist a long period of time. At this moment, those relics are cultural heritage that must be preserved and the authenticity maintained. Indonesia, a country consist of various tribes with many cultural heritages, one of them is the city of Lasem. Lasem city lies in the northern part of Central Java since the Majapahit kingdom era (13th century) poses as a busy harbor city and a trading center. Lasem is one of the residences of Chinese immigrants in Java, seen by the domination of Chinese architectural building styles. The residential was built since the 15th century and the building has the courtyard which is different from other China’s building in another part of Java. This city loses ground since the trade activity experience difficulties during the Japanese colonial era and continues after the Indonesian independence time. Many Chinese people left Lasem city and let the buildings empty not maintained. This paper will present the result of observation to Chinese architectural style buildings in Lasem city which still hold out until this moment. Using typo morphology method, the case study is chosen based on the transformation type. The occurring transformation is parallel with adaptive reuse concept as an effort to revitalize the existence of the buildings. With this concept, it is expected that the buildings could be re functioned and the glory of the foretime Lasem city could be experienced again. Intervention from the local government is expected, issuing regulations, hoping the new building functions won’t ruin the cultural heritage but instead beautifies it.

Keywords: adaptive re-use, brown field area, building transformation, Lasem city

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Authors: Amos Olajide Oluyege, Emmanuel Uchechukwu Opara, Sunday Adeniyi Adedutan, Joseph Adeola Fuwape

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This study was conducted to determine the durability of wood-cement particleboards when exposed to attack by subterranean termites, Macrotermes subhylinus. The boards were made from Terminalia superba and Gmelina arborea wood sawdust at nominal board densities (BD) of 1000, 900, and 800 kg/m³ using wood-cement mixing ratios (MR) of 3:1, 2.5:1, 2:1, and 1:1. Above ground durability tests against termite attack were carried out according to ASTM D 2017 for 14 weeks. Results of visual assessment of the wood cement particleboards show that all the board samples had a visual rating that was not less than 7 (i.e., moderate attack) for both species irrespective of the MR and BD. T. superba boards were found to have higher resistance to termite attack compared to their G. arborea counterparts. The mean values for weight loss following exposure ranged from 1.93 to 6.13% and 3.24 to 12.44%. Analysis of variance (ANOVA) results of the weight loss assessment revealed a significant (p < 0.05) effect of species and mixing ratio on the weight loss of the boards due to termite attack with F(₁,₇₂) = 92.890 and P = 0.000 and F(₃,₇₂) = 8.318 and p = 0.000, while board density did not have any significant effect (p > 0.05) with F (₂,₇₂) = 1.307 and p = 0.277. Thus, boards made from a higher mixing ratio had better resistance against termite attacks. Thus, it can be concluded that the durability of cement-bonded particleboards when exposed to subterranean termite attack is not only dependent on the quality of the wood raw material (species) but also on the enhanced protection imparted by the cement matrix; the protection increased with increase in cement/wood mixing ratio.

Keywords: cement-bonded particleboard, mixing ratio, board density, Gmelina arborea, Terminalia superba

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Authors: Angelos Evangelou, Katerina Loizou, Loukas Koutsokeras, Orestes Marangos, Giorgos Constantinides, Stylianos Yiatros, Katerina Sofocleous, Vasileios Drakonakis

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Owing to their outstanding strength to weight properties, carbon fiber reinforced polymer (CFRPs) composites have attracted significant attention finding use in various fields (sports, automotive, transportation, etc.). The current momentum indicates that there is an increasing demand for their employment in high value bespoke applications such as avionics and electronic casings, damage sensing structures, EMI (electromagnetic interference) structures that dictate the use of materials with increased electrical conductivity both in-plane and through the thickness. Several efforts by research groups have focused on enhancing the through-thickness electrical conductivity of FRPs, in an attempt to combine the intrinsically high relative strengths exhibited with improved z-axis electrical response as well. However, only a limited number of studies deal with printing of nano-enhanced polymer inks to produce a pattern on dry fabric level that could be used to fabricate CFRPs with improved through thickness electrical conductivity. The present study investigates the employment of screen-printing process on technical dry fabrics using nano-reinforced polymer-based inks to achieve the required through thickness conductivity, opening new pathways for the application of fiber reinforced composites in niche products. Commercially available inks and in-house prepared inks reinforced with electrically conductive nanoparticles are employed, printed in different patterns. The aim of the present study is to investigate both the effect of the nanoparticle concentration as well as the droplet patterns (diameter, inter-droplet distance and coverage) to optimize printing for the desired level of conductivity enhancement in the lamina level. The electrical conductivity is measured initially at ink level to pinpoint the optimum concentrations to be employed using a “four-probe” configuration. Upon printing of the different patterns, the coverage of the dry fabric area is assessed along with the permeability of the resulting dry fabrics, in alignment with the fabrication of CFRPs that requires adequate wetting by the epoxy matrix. Results demonstrated increased electrical conductivities of the printed droplets, with increase of the conductivity from the benchmark value of 0.1 S/M to between 8 and 10 S/m. Printability of dense and dispersed patterns has exhibited promising results in terms of increasing the z-axis conductivity without inhibiting the penetration of the epoxy matrix at the processing stage of fiber reinforced composites. The high value and niche prospect of the resulting applications that can stem from CFRPs with increased through thickness electrical conductivities highlights the potential of the presented endeavor, signifying screen printing as the process to to nano-enable z-axis electrical conductivity in composite laminas. This work was co-funded by the European Regional Development Fund and the Republic of Cyprus through the Research and Innovation Foundation (Project: ENTERPRISES/0618/0013).

Keywords: CFRPs, conductivity, nano-reinforcement, screen-printing

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Authors: R. T. Aggangan, R. J. Cabangon

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Bamboo is getting worldwide attention over the last 20 to 30 years due to numerous uses and it is regarded as the closest material that can be used as substitute to wood. In the domestic market, high quality bamboo products are sold in high-end markets while lower quality products are generally sold to medium and low income consumers. The global market in 2006 stands at about 7 billion US dollars and was projected to increase to US$ 17 B from 2015 to 2020. The Philippines had been actively producing and processing bamboo products for the furniture, handicrafts and construction industry. It was however in 2010 that the Philippine bamboo industry was formalized by virtue of Executive Order 879 that stated that the Philippine bamboo industry development is made a priority program of the government and created the Philippine Bamboo Industry Development Council (PBIDC) to provide the overall policy and program directions of the program for all stakeholders. At present, the most extensive use of bamboo is for the manufacture of engineered bamboo for school desks for all public schools as mandated by EO 879. Also, engineered bamboo products are used for high-end construction and furniture as well as for handicrafts. Development of cheap adhesives, preservatives, and finishing chemicals from local species of plants, development of economical methods of drying and preservation, product development and processing of lesser-used species of bamboo, development of processing tools, equipment and machineries are the strategies that will be employed to reduce the price and mainstream engineered bamboo products in the local and foreign market. In addition, processing wastes from bamboo can be recycled into fuel products such as charcoal are already in use. The more exciting possibility, however, is the production of bamboo pellets that can be used as a substitute for wood pellets for heating, cooking and generating electricity.

Keywords: bamboo charcoal and light distillates, engineered bamboo, furniture and handicraft industries, housing and construction, pellets

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Authors: Yetti Marlida, Harnentis, Yuliaty Shafan Nur

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Background: Tempoyak is a dish derived from fermented durian fruit. Tempoyak is a food consumed as a side dish when eating rice. Besides being eaten with rice, tempoyak can also be eaten directly. But this is rarely done because many cannot stand the sour taste and aroma of the tempoyak itself. In addition, tempoyak can also be used as a seasoning. The taste of tempoyak is acidic, this occurs because of the fermentation process in durian fruit meat which is the raw material. Tempoyak is already very well known in Indonesia, especially in Padang, Bengkulu, Palembang, Lampung, and Kalimantan. Besides that, this food is also famous in Malaysia. The purpose of this research is to improvement production of γ-aminobutyric acid (GABA) by Lactobacillus plantarum isolated from indigenous fermented durian (tempoyak). Selected Lactic Acid Bacteria (LAB) previously isolated from indigenous fermented durian (tempoyak) that have ability to produce γ-aminobutyric acid (GABA). The study was started with identification of selected LAB by 16 S RNA, followed optimation of GABA production by culture condition using different initial pH, temperature, glutamate concentration, incubation time, carbon and nitrogen sources. Results: The result from indentification used polymerase chain reaction of 16S rRNA gene sequences and phylogenetic analysis was Lactobacillus plantarum (coded as Y3) with a sequenced length of 1400bp. The improvement of Gaba production was found highest at pH: 6.0; temperature: 30 °C; glutamate concentration: 0.4%; incubation time: 60 h; glucose and yeast extract as carbon and nitrogen sources. Conclusions: GABA can be produced with the optimum condition fermentation were 66.06 mM.

Keywords: lactic acid bacteria, γ-amino butyric acid, indigenous fermented durian, PCR

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Authors: Rodrigo Arnaldo Scarpel

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Trend following is a widely accepted investment strategy that adopts a rule-based trading mechanism that rather than striving to predict market direction or on information gathering to decide when to buy and when to sell a stock. Thus, in trend following one must respond to market’s movements that has recently happen and what is currently happening, rather than on what will happen. Optimally, in trend following strategy, is to catch a bull market at its early stage, ride the trend, and liquidate the position at the first evidence of the subsequent bear market. For applying the trend following strategy one needs to find the trend and identify trade signals. In order to avoid false signals, i.e., identify fluctuations of short, mid and long terms and to separate noise from real changes in the trend, most academic works rely on moving averages and other technical analysis indicators, such as the moving average convergence divergence (MACD) and the relative strength index (RSI) to uncover intelligible stock trading rules following trend following strategy philosophy. Recently, some works has applied machine learning techniques for trade rules discovery. In those works, the process of rule construction is based on evolutionary learning which aims to adapt the rules to the current environment and searches for the global optimum rules in the search space. In this work, instead of focusing on the usage of machine learning techniques for creating trading rules, a time series trend classification employing a semi-supervised approach was used to early identify both the beginning and the end of upward and downward trends. Such classification model can be employed to identify trade signals and the decision-making procedure is that if an up-trend (down-trend) is identified, a buy (sell) signal is generated. Semi-supervised learning is used for model training when only part of the data is labeled and Semi-supervised classification aims to train a classifier from both the labeled and unlabeled data, such that it is better than the supervised classifier trained only on the labeled data. For illustrating the proposed approach, it was employed daily trade information, including the open, high, low and closing values and volume from January 1, 2000 to December 31, 2022, of the São Paulo Exchange Composite index (IBOVESPA). Through this time period it was visually identified consistent changes in price, upwards or downwards, for assigning labels and leaving the rest of the days (when there is not a consistent change in price) unlabeled. For training the classification model, a pseudo-label semi-supervised learning strategy was used employing different technical analysis indicators. In this learning strategy, the core is to use unlabeled data to generate a pseudo-label for supervised training. For evaluating the achieved results, it was considered the annualized return and excess return, the Sortino and the Sharpe indicators. Through the evaluated time period, the obtained results were very consistent and can be considered promising for generating the intended trading signals.

Keywords: evolutionary learning, semi-supervised classification, time series data, trading signals generation

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Authors: Carlos E. Rodríguez-Rodríguez, Karla Ruiz-Hidalgo, Kattia Madrigal-Zúñiga, Juan Salvador Chin-Pampillo, Mario Masís-Mora, Elizabeth Carazo-Rojas

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One of the main causes of contamination linked to agricultural activities is the spillage and disposal of pesticides, especially during the loading, mixing or cleaning of agricultural spraying equipment. One improvement in the handling of pesticides is the use of biopurification systems (BPS), simple and cheap degradation devices where the pesticides are biologically degraded at accelerated rates. The biologically active core of BPS is the biomixture, which is constituted by soil pre-exposed to the target pesticide, a lignocellulosic substrate to promote the activity of ligninolitic fungi and a humic component (peat or compost), mixed at a volumetric proportion of 50:25:25. Considering the known ability of lignocellulosic fungi to degrade a wide range of organic pollutants, and the high amount of lignocellulosic waste used in biomixture preparation, the bioaugmentation of biomixtures with these fungi represents an interesting approach for improving biomixtures. The present work aimed at evaluating the effect of the bioaugmentation of rice husk based biomixtures with the fungus Trametes versicolor in the removal of the insectice/nematicide carbofuran (CFN) and to optimize the composition of the biomixture to obtain the best performance in terms of CFN removal and mineralization, reduction in formation of transformation products and decrease in residual toxicity of the matrix. The evaluation of several lignocellulosic residues (rice husk, wood chips, coconut fiber, sugarcane bagasse or newspaper print) revealed the best colonization by T. versicolor in rice husk. Pre-colonized rice husk was then used in the bioaugmentation of biomixtures also containing soil pre-exposed to CFN and either peat (GTS biomixture) or compost (GCS biomixture). After spiking with 10 mg/kg CBF, the efficiency of the biomixture was evaluated through a multi-component approach that included: monitoring of CBF removal and production of CBF transformation products, mineralization of radioisotopically labeled carbofuran (14C-CBF) and changes in the toxicity of the matrix after the treatment (Daphnia magna acute immobilization test). Estimated half-lives of CBF in the biomixtures were 3.4 d and 8.1 d in GTS and GCS, respectively. The transformation products 3-hydroxycarbofuran and 3-ketocarbofuran were detected at the moment of CFN application, however their concentration continuously disappeared. Mineralization of 14C-CFN was also faster in GTS than GCS. The toxicological evaluation showed a complete toxicity removal in the biomixtures after 48 d of treatment. The composition of the GCS biomixture was optimized using a central composite design and response surface methodology. The design variables were the volumetric content of fungally pre-colonized rice husk and the volumetric ratio compost/soil. According to the response models, maximization of CFN removal and mineralization rate, and minimization in the accumulation of transformation products were obtained with an optimized biomixture of composition 30:43:27 (pre-colonized rice husk:compost:soil), which differs from the 50:25:25 composition commonly employed in BPS. Results suggest that fungal bioaugmentation may enhance the performance of biomixtures in CFN removal. Optimization reveals the importance of assessing new biomixture formulations in order to maximize their performance.

Keywords: bioaugmentation, biopurification systems, degradation, fungi, pesticides, toxicity

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Authors: Saidalavi Kannattippadi

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It is a culture based study on revealing how the indebtedness of the west belongs to the moral and scientific culture of Islam, even to such a way to be said there was no room for renaissance and the enlightment of the west without the active intervention of the Islamic culture in thoughts and activities of the European thinkers. The study focuses on the exact causes that led the west to the renaissance and goes through analyzing each of historical evidences for confirming the continuous cultural assimilations that occurred between east and west, through transmissions of knowledge, translations of unique treatises, study trips and so on. The west had deeply influenced by the thought and culture of Islam after having a long bitter experience from the blind rituals and customs introduced by the church and was expecting for a movement that can raise them upwards from the bankruptcy of morality and spirituality. The sequence of crusades and voyages of thinkers from west to eastern wards made the western people aware of the best culture ever found in the world as in name of Islam and they become ready to assimilate its notable cultural values and to borrow its cultural achievements. The west had two types of influences from the Islam; moral and scientific. the uprooting of untouchablitlity and racism from western society and their accepting the ideologies of equality and fraternity are moral influence and the innumerable inventions and discoveries found in modern science and technology are the scientific influences. Without the frantic efforts of Muslims in translating, modifying and commenting the science and philosophy of the Greek the west would not have even a chance to peep to the cultural values of the Greek. Here the Muslims are the guides and channels through which the west got educated and well cultured. The study also briefly sheds light on the cultural achievements of Muslims in material science, human science, etc.

Keywords: cultural assimilation, culture and civilization, indebtedness, Muslim world, west, translation, transmission

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Authors: Mourad Morsli, Mohamed Tahiri, Azzedine Samdi

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The Cities are the urbanized territories most favorable to the consumption of resources (materials, energy). In Morocco, the economic capital Casablanca is one of them, with its 4M inhabitants and its 60% share in the economic and industrial activity of the kingdom. In the absence of legal status in force, urban development has favored the generation of millions of tons of demolition and construction waste scattered in open spaces causing a significant nuisance to the environment and citizens. Hence the main objective of our work is to valorize concrete waste. The representative wastes are mainly concrete, concrete, and fired clay bricks, ceramic tiles, marble panels, gypsum, and scrap metal. The work carried out includes: geolocation with a combination of artificial intelligence, GIS, and Google Earth, which allowed the estimation of the quantity of these wastes per site; then the sorting, crushing, grinding, and physicochemical characterization of the collected samples allowed the definition of the exploitation ways for each extracted fraction for integrated management of the said wastes. In the present work, we proceeded to the exploitation of the fractions obtained after sieving the representative samples to incorporate them in the manufacture of new ecological materials for construction. These formulations prepared studies have been tested and characterized: physical criteria (specific surface, resistance to flexion and compression) and appearance (cracks, deformation). We will present in detail the main results of our research work and also describe the specific properties of each material developed.

Keywords: demolition and construction waste, GIS combination software, inert waste recovery, ecological materials, Casablanca, Morocco

Procedia PDF Downloads 136

Authors: Piyaorn Wajanatinapart, Diane R. Lauver

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The number of persons with dementia (PWD) has increased. Informal caregivers are the major providing care. They can have perceived gains and burdens. Caregivers who reported high in perceived gains may report low in burdens and better health. Gaps of caregiving literature were: no report psychometrics in a few studies and unclear definitions of gains; most studies with no theory-guided and conducting in Western countries; not fully described relationships among caregiving variables: motivations, satisfaction with psychological needs, social support, gains, burdens, and physical and psycho-emotional health. Those gaps were filled by assessing psychometric properties of selected measures, providing clearly definitions of gains, using self-determination theory (SDT) to guide the study, and developing the study in Thailand. The study purposes were to evaluate six measures for internal consistency reliability, content validity, and construct validity. This study also examined relationships of caregiving variables: motivations (controlled and autonomous motivations), satisfaction with psychological needs (autonomy, competency, and relatedness), perceived social support, perceived gains, perceived burdens, and physical and psycho-emotional health. This study was a cross-sectional and correlational descriptive design with two convenience samples. Sample 1 was five Thai experts to assess content validity of measures. Sample 2 was 146 Thai caregivers of PWD to assess construct validity, reliability, and relationships among caregiving variables. Experts rated questionnaires and sent them back via e-mail. Caregivers answered questionnaires at clinics of four Thai hospitals. Data analysis was used descriptive statistics and bivariate and multivariate analyses using the composite indicator structural equation model to control measurement errors. For study results, most caregivers were female (82%), middle age (M =51.1, SD =11.9), and daughters (57%). They provided care for 15 hours/day with 4.6 years. The content validity indices of items and scales were .80 or higher for clarity and relevance. Experts suggested item revisions. Cronbach’s alphas were .63 to .93 of ten subscales of four measures and .26 to .57 of three subscales. The gain scale was acceptable for construct validity. With controlling covariates, controlled motivations, the satisfaction with three subscales of psychological needs, and perceived social support had positive relationships with physical and psycho-emotional health. Both satisfaction with autonomy subscale and perceived social support had negative relationship with perceived burdens. The satisfaction with three subscales of psychological needs had positive relationships among them. Physical and psycho-emotional health subscales had positive relationships with each other. Furthermore, perceived burdens had negative relationships with physical and psycho-emotional health. This study was the first use SDT to describe relationships of caregiving variables in Thailand. Caregivers’ characteristics were consistent with literature. Four measures were valid and reliable except two measures. Breadth knowledge about relationships was provided. Interpretation of study results was cautious because of using same sample to evaluate psychometric properties of measures and relationships of caregiving variables. Researchers could use four measures for further caregiving studies. Using a theory would help describe concepts, propositions, and measures used. Researchers may examine the satisfaction with psychological needs as mediators. Future studies to collect data with caregivers in communities are needed.

Keywords: caregivers, caregiving, dementia, measures

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Authors: Buğra Sinmez

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In some countries, such as China, Turkey, andseveralEuropeanUnionnations, the therailwaypavementstructuralsystem has recently undergonerapid growth as a vital element of the transportation infrastructure, particularlyfortheuse of high-speed trains. It is vitaltoconsiderthe High-SpeedInfrastructureDemandwhendevelopingandconstructingtherailwaypavementstructure. HSRL can create more substantial ldifficultiestotheballastorbaselayer of regularlyusedballastedrailwaypavementsthanstandardrailwaytrains. The deterioration of the theballastorbaselayermayleadtosubstructuredegradation, which might lead to safety concerns and catastrophicincidents. As a result, the efficiency of railways will be impactedbylargecargoesorhigh-speed trains. A railwaypavement construction can be strengthened using geosyntheticmaterials in theballastorfoundationlayer as a countermeasure. However, there is still a need in the literature to quantifytheinfluence of geosynthetic materials, particularlygeogrid, on the mechanical responses of railwaypavementstructuresto HSRL loads which is essential knowledge in supporting the selection of appropriate material and geogridinstallationposition. As a result, the purpose of this research is to see how a geogridreinforcementlayermayaffectthekeyfeatures of a ballastedrailwaypavementstructure, with a particular focus on the materialtypeandgeogridplacementpositionthatmayassistreducethe rate of degradation of the therailwaypavementstructuresystem. Thisstudyusesnumericalmodeling in a genuinerailwaycontexttovalidatethebenefit of geogrid reinforcement. The usage of geogrids in the railway system has been thoroughly researched in the technical literature. Three distinct types of geogrid installed at two distinct positions (i.e.,withintheballastlayer, betweentheballastandthesub-ballast layer) within a railwaypavementconstructionwereevaluatedunder a variety of verticalwheelloadsusing a three-dimensional (3D) finite element model. As a result, fouralternativegeogridreinforcementsystemsweremodeledtoreflectdifferentconditions in the ballastedrailwaysystems (G0: no reinforcement; G1: reinforcedwithgeogridhavingthelowestdensityandYoung'smodulus; G2: reinforcedwithgeogridhavingtheintermediateYoung'smodulusanddensity; G3: reinforcedwithgeogridhavingthegreatestdensityandYoung'smodulus). Themechanicalreactions of the railway, such as verticalsurfacedeflection, maximumprimarystressandstrain, andmaximumshearstress, werestudiedandcomparedbetweenthefourgeogridreinforcementscenariosandfourverticalwheelloadlevels (i.e., 75, 100, 150, and 200 kN). Differences in the mechanical reactions of railwaypavementconstructionsowingtotheuse of differentgeogridmaterialsdemonstratethebenefits of suchgeosynthetics in ballast. In comparison to a non-reinforcedrailwaypavementconstruction, thereinforcedconstructionsfeaturedecreasedverticalsurfacedeflection, maximum shear stress at the sleeper-ballast contact, and maximum main stress at the bottom of the ballast layer. As a result, addinggeogridtotheballastlayerandbetweentheballastandsub-ballast layer in a ballastedrailwaypavementconstruction has beenfoundtolowercriticalshearand main stresses as well as verticalsurfacedeflection.

Keywords: geosynthetics, geogrid, railway, transportation

Procedia PDF Downloads 182

Authors: Virginia Andrea Garrido Meirelles

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Noah Webster was a lexicographer and a language reformer and is considered the ‘Father of American Scholarship and Education’ because of the exceptional contributions he made as a teacher and grammarian. The goal of this study is to show that the success of his plan can be explained by the fact that it matched the language-in-education policies of his time. To accomplish that goal the present study analyzes the Massachusetts School Laws of 1642, 1647 and 1648 and compares them to the preface of the first edition of The Grammatical Institute of the English Language. The referred laws were three legislative acts enacted in the Massachusetts Colony and replicated almost identically in the other New England colonies. The purpose of those laws was to eradicate pauperism and poverty, on the one side, and to disseminate the idea of right citizenship, on the other. However, until the Declaration of Independence in 1776, all the primers used in the colony were printed in Britain. In 1783, Noah Webster published the first part of his Grammatical Institute of the English Language. In this book, the author states that his goal is to promote the republican principles that guide the civil rights of that time. The material included many texts taken from the Bible to inspire aversion to inadequate behavior and preference for service and good manners. In addition, its goal was to present ‘a new plan of reducing the pronunciation of our language to an easy standard,’ and in that way, create a unified language to abolish ignorance and language corruption. The comparison between the laws and Webster’s Spelling Book shows that the book is the result of the historical and political situation when it was conceived and it satisfied the requirements of the language-in-education policies of the time.

Keywords: American English, language policy, the Massachusetts school laws, webster's spelling book

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Authors: Gulam Anwer Khan, A. Gautam

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Background: The arch of aorta is a large artery that arches over the root of the left lung and connects the ascending aorta and descending aorta. It is situated in the superior mediastinum behind the manubrium sterni. It gives off three major branches i.e. brachiocephalic trunk, left common carotid artery and left subclavian artery arising from the superior surface of arch of aorta from right to left. Material and Methods: This was a descriptive study. It was carried out in 44 cadavers, obtained during dissections for undergraduates of Department of Anatomy, Chitwan Medical College, Bharatpur, Chitwan, between March 2015 to October 2016. Cadavers of both sexes were included in the present study. The arch of aorta was dissected and exposed according to the methods described by Romanes in Cunningham’s manual of practical anatomy. Results: Out of 44 dissected cadavers, 35 (79.54%) were male and 9 (20.46%) were female cadavers. The normal branching pattern of the arch of aorta was encountered in 28 (63.64%) cadavers and the remaining 16 (36.36%) cadavers showed variations in the branching pattern of arch of aorta. Two different types of variations on the branching pattern of arch of aorta were noted in the present study, in which 12 (27.27%) cadavers had common trunk of the Arch of Aorta. In 3 (5.00%) male cadavers, we found the origin of the Thyroid ima artery. This variation was noted in 1(1.66%) female cadaver. Conclusion: The present study carried out on adult human cadavers’ revealed wide variations in the branching pattern of the arch of ao rta. These variations are of clinical significance and also very useful for the anatomists, radiologists, anesthesiologists, surgeons for practice during angiography, instrumentation, supra-aortic thoracic, head and neck surgery.

Keywords: arch of aorta, brachiocephalic trunk, left common carotid artery, left subclavian artery, Thyroidea ima artery

Procedia PDF Downloads 335

Authors: Anam Layla, Qamar Abbas Syed, Tahir Zahoor, Muhammad Shahid

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Brassicaceae sprouts are promising candidates for functional food because of their unique phytochemistry and high nutrient density compared to their seeds and matured vegetables. Despite being admired for their health-promoting properties, white cabbage sprouts have been least explored for their nutritional significance and behavior to lactic acid fermentation. This study aimed to investigate the role of lactic acid fermentation i.e., inoculum vs. spontaneous, in reducing intrinsic toxicants load and improving nutrients delivering potential of the white cabbage sprouts. White cabbage sprouts with a 5 – 7 cm average size were processed as raw, blanched, Lactiplantibacillus plantarum inoculated fermentation and spontaneous fermentation. Plant material was dehydrated at 40˚C and evaluated for microbiological quality, macronutrients, minerals, and anti-nutrient contents. The results indicate L. plantarum inoculum fermentation of blanched cabbage sprouts (IF-BCS) to increase lactic acid bacteria count of the sprouts from 0.97 to 8.47 log CFU/g. Compared with the raw cabbage sprouts (RCS), inoculum fermented-raw cabbage sprouts (IF-RCS), and spontaneous fermented-raw cabbage sprouts (SF-RCS), the highest content of Ca (447 mg/ 100g d.w.), Mg (204 mg/100g d.w.), Fe (9.3 mg/100g d.w.), Zn (5 mg/100g d.w.) and Cu (0.5 mg/100g d.w.) were recorded in IF-BCS. L. plantarum led fermentation of BCS demonstrated a reduction in phytates, tannins, and oxalates contents at a rate of 42%, 66%, and 53%, respectively, while standalone lactic acid fermentation of the raw sprouts reduced the burden of anti-nutrients in a range between 32 to 56%. The results suggest L. plantarum led lactic acid fermentation coupled with sprouts blanching is the most promising way to improve the nutritional quality and safety of the white cabbage sprouts.

Keywords: lactic acid fermentation, anti-nutrients, mineral content, nutritional quality

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Authors: Borja Ruiz de Arbulo Alonso

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This paper analyzes the impact of flipped instruction in adult learners of Spanish as a second language in a face-to-face course at Boston University. Given the limited amount of contact hours devoted to studying world languages in the American higher education system, implementing strategies to free up classroom time for communicative language practice is key to ensure student success in their learning process. In an effort to improve the way adult learners acquire a second language, this paper examines the role that regular pre-class and web-based exposure to Spanish grammar plays in student performance at the end of the academic term. It outlines different types of web-based pre-class activities and compares this approach to more traditional classroom practice. To do so, this study works for three months with two similar groups of adult learners in an intermediate-level Spanish class. Both groups use the same course program and have the same previous language experience, but one receives an additional set of instructor-made online materials containing a variety of grammar explanations and online activities that need to be reviewed before attending class. Since the online activities cover material and concepts that have not yet been studied in class, students' oral and written production in both groups is measured by means of a writing activity and an audio recording at the end of the three-month period. These assessments will ascertain the effects of exposing the control group to the grammar of the target language prior to each lecture throughout and demonstrate where flipped instruction helps adult learners of Spanish achieve higher performance, but also identify potential problems.

Keywords: educational technology, flipped classroom, second language acquisition, student success

Procedia PDF Downloads 125

Authors: Po-Ting Chen, Santhanamoorthi Nachimuthu, Jyh-Chiang Jiang

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Classical molecular dynamics (CMD) simulations are highly efficient for material simulations but have limited accuracy. In contrast, ab initio molecular dynamics (AIMD) provides high precision by solving the Kohn–Sham equations yet requires significant computational resources, restricting the size of systems and time scales that can be simulated. To address these challenges, we employed NequIP, a machine learning model based on an E(3)-equivariant graph neural network, to accelerate molecular dynamics simulations of a 1M LiPF6 in EC/EMC (v/v 3:7) for Li battery applications. AIMD calculations were initially conducted using the Vienna Ab initio Simulation Package (VASP) to generate highly accurate atomic positions, forces, and energies. This data was then used to train the NequIP model, which efficiently learns from the provided data. NequIP achieved AIMD-level accuracy with significantly less training data. After training, NequIP was integrated into the LAMMPS software to enable molecular dynamics simulations of larger systems over longer time scales. This method overcomes the computational limitations of AIMD while improving the accuracy limitations of CMD, providing an efficient and precise computational framework. This study showcases NequIP’s applicability to electrolyte systems, particularly for simulating the dynamics of LiPF6 ionic mixtures. The results demonstrate substantial improvements in both computational efficiency and simulation accuracy, highlighting the potential of machine learning models to enhance molecular dynamics simulations.

Keywords: lithium-ion batteries, electrolyte simulation, molecular dynamics, neural network

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Authors: Syed Dawood M. Taimur

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Background: Peripheral arterial disease (PAD) is under diagnosed in primary care practices, yet the extent of unrecognized PAD in patients with coronary artery disease (CAD) is unknown. Objective: To assess the prevalence of previously unrecognized PAD in patients undergoing coronary angiogram and to determine the relationship between the presence of PAD and severity of CAD. Material & Methods: This five years retrospective study was conducted at an invasive lab of the department of Cardiology, Ibrahim Cardiac Hospital & Research Institute from January 2010 to December 2014. Total 77 patients were included in this study. Study variables were age, sex, risk factors like hypertension, diabetes mellitus, dyslipidaemia, smoking habit and positive family history for ischemic heart disease, coronary artery and peripheral artery profile. Results: Mean age was 56.83±13.64 years, Male mean age was 53.98±15.08 years and female mean age was 54.5±1.73years. Hypertension was detected in 55.8%, diabetes in 87%, dyslipidaemia in 81.8%, smoking habits in 79.2% and 58.4% had a positive family history. After catheterization 88.3% had peripheral arterial disease and 71.4% had coronary artery disease. Out of 77 patients, 52 had both coronary and peripheral arterial disease which was statistically significant (p < .014). Coronary angiogram revealed 28.6% (22) patients had triple vessel disease, 23.3% (18) had single vessel disease, 19.5% (15) had double vessel disease and 28.6% (22) were normal coronary arteries. The peripheral angiogram revealed 54.5% had superficial femoral artery disease, 26% had anterior tibial artery disease, 27.3% had posterior tibial artery disease, 20.8% had common iliac artery disease, 15.6% had common femoral artery disease and 2.6% had renal artery disease. Conclusion: There is a strong and definite correlation between coronary and peripheral arterial disease. We found that cardiovascular risk factors were in fact risk factors for both PAD and CAD.

Keywords: coronary artery disease (CAD), peripheral artery disease(PVD), risk, factors, correlation, cathetarization

Procedia PDF Downloads 427