Search results for: negative transfer

Authors: Maggie Hui

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Risk management is not a new concept; however, it is an uncharted area as applied to the translation process and translator training. Risk managers are responsible for managing risk, i.e. adopting strategies with the intention to minimize loss and maximize gains in spite of uncertainty. Which risk strategy to use often depends on the frequency of an event (i.e. probability) and the severity of its outcomes (i.e. impact). This is basically the way translation/localization project managers handle risk management. Although risk management could involve both positive and negative impacts, impact seems to be always negative in professional translators’ management models, e.g. how many days of project time are lost or how many clients are lost. However, for analysis of translation performance, the impact should be possibly positive (e.g. increased readability of the translation) or negative (e.g. loss of source-text information). In other words, the straight business model of risk management is not directly applicable to the study of risk management in the rendition process. This research aims to explore trainee translators’ risk managing while translating in a simulated setting that involves translator-client relations. A two-cycle experiment involving two roles, the translator and the simulated client, was carried out with a class of translation students to test the effects of the main variable of peer-group interaction. The researcher made use of a user-friendly screen-voice recording freeware to record subjects’ screen activities, including every word the translator typed and every change they made to the rendition, the websites they browsed and the reference tools they used, in addition to the verbalization of their thoughts throughout the process. The research observes the translation procedures subjects considered and finally adopted, and looks into the justifications for their procedures, in order to interpret their risk management. The qualitative and quantitative results of this study have some implications for translator training: (a) the experience of being a client seems to reinforce the translator’s risk aversion; (b) there is a wide gap between the translator’s internal risk management and their external presentation of risk; and (c) the use of role-playing simulation can empower students’ learning by enhancing their attitudinal or psycho-physiological competence, interpersonal competence and strategic competence.

Keywords: risk management, role-playing simulation, translation pedagogy, translator-client relations

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Authors: Alexandra Tucaliuc, Alexandra C. Blaga, Anca I. Galaction, Lenuta Kloetzer, Dan Cascaval

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Ergosterol (ergosta-5,7,22-trien-3β-ol), also known as provitamin D2, is the precursor of vitamin D2 (ergocalciferol), because it is converted under UV radiation to this vitamin. The natural sources of ergosterol are mainly the yeasts (Saccharomyces sp., Candida sp.), but it can be also found in fungus (Claviceps sp.) or plants (orchids). In the yeasts cells, ergosterol is accumulated in membranes, especially in free form in the plasma membrane, but also as esters with fatty acids in membrane lipids. The chemical synthesis of ergosterol does not represent an efficient method for its production, in these circumstances, the most attractive alternative for producing ergosterol at larger-scale remains the aerobic fermentation using S. cerevisiae on glucose or by-products from agriculture of food industry as substrates, in batch or fed-batch operating systems. The aim of this work is to analyze comparatively the influence of aeration efficiency on ergosterol production by S. cerevisiae in batch and fed-batch fermentations, by considering different levels of mixing intensity, aeration rate, and n-dodecane concentration. The effects of the studied factors are quantitatively described by means of the mathematical correlations proposed for each of the two fermentation systems, valid both for the absence and presence of oxygen-vector inside the broth. The experiments were carried out in a laboratory stirred bioreactor, provided with computer-controlled and recorded parameters. n-Dodecane was used as oxygen-vector and the ergosterol content inside the yeasts cells has been considered at the fermentation moment related to the maximum concentration of ergosterol, 9 hrs for batch process and 20 hrs for fed-batch one. Ergosterol biosynthesis is strongly dependent on the dissolved oxygen concentration. The hydrocarbon concentration exhibits a significant influence on ergosterol production mainly by accelerating the oxygen transfer rate. Regardless of n-dodecane addition, by maintaining the glucose concentration at a constant level in the fed-batch process, the amount of ergosterol accumulated into the yeasts cells has been almost tripled. In the presence of hydrocarbon, the ergosterol concentration increased by over 50%. The value of oxygen-vector concentration corresponding to the maximum level of ergosterol depends mainly on biomass concentration, due to its negative influences on broth viscosity and interfacial phenomena of air bubbles blockage through the adsorption of hydrocarbon droplets–yeast cells associations. Therefore, for the batch process, the maximum ergosterol amount was reached for 5% vol. n-dodecane, while for the fed-batch process for 10% vol. hydrocarbon.

Keywords: bioreactors, ergosterol, fermentation, oxygen-vector

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Authors: Anas Alsuhaibani

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Observing debate and discussion over social media has been found to be a promising tool to investigate different types of opinion. On 23 June 2016, Brexit voters in the UK decided to depart from the EU, with 51.9% voting to leave. On Twitter, there had been a massive debate in this context, and the hashtag Brexit was allocated as number six of the most tweeted hashtags across the globe in 2016. The study aimed to investigate the sentiment and themes expressed in a sample of tweets during a political event (Brexit) in 2016. A sentiment and thematic analysis was conducted on 1304 randomly selected tweets tagged with the hashtag Brexit in Twitter for the period from 10 June 2016 to 7 July 2016. The data were coded manually into two code frames, sentiment and thematic, and the reliability of coding was assessed for both codes. The sentiment analysis of the selected sample found that 45.63% of tweets conveyed negative emotions while there were only 10.43% conveyed positive emotions. It also surprisingly resulted that 29.37% were factual tweets, where the tweeter expressed no sentiment and the tweet conveyed a fact. For the thematic analysis, the economic theme dominated by 23.41%, and almost half of its discussion was related to business within the UK and the UK and global stock markets. The study reported that the current UK government and relation to campaign themes were the most negative themes. Both sentiment and thematic analyses found that tweets with more than one opinion or theme were rare, 8.29% and 6.13%, respectively.

Keywords: Brexit, political opinion mining, social media, twitter

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Authors: Vladimir Mantsevich, Natalya Maslova, Petr Arseyev

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We investigated the tunneling current peculiarities in the system of two coupled by means of the external field quantum dots (QDs) weakly connected to the electrodes in the presence of Coulomb correlations between localized electrons by means of Heisenberg equations for pseudo operators with constraint. Special role of multi-electronic states was demonstrated. Various single-electron levels location relative to the sample Fermi level and to the applied bias value in symmetric tunneling contact were investigated. Rabi frequency tuning results in the single-electron energy levels spacing. We revealed the appearance of negative tunneling conductivity and demonstrated multiple switching "on" and "off" of the tunneling current depending on the Coulomb correlations value, Rabi frequency amplitude and energy levels spacing. We proved that Coulomb correlations strongly influence the system behavior. We demonstrated the presence of multi-stability in the coupled QDs with Coulomb correlations when single value of the tunneling current amplitude corresponds to the two values of Rabi frequency in the case when both single-electron energy levels are located slightly above eV and are close to each other. This effect disappears when the single-electron energy levels spacing increases.

Keywords: Coulomb correlations, negative tunneling conductivity, quantum dots, rabi frequency

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Authors: Hoa Thi Hoang, Stephan Sass, Michael U. Kumke

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Concanavalin A (conA) is a protein has been widely used in sensor system based on its specific binding to α-D-Glucose or α-D-Manose. For glucose sensor using conA, either fluoresence based techniques with intensity based or lifetime based are used. In this research, liposomes made from phospholipids were used as a biomimetic membrane system. In a first step, novel building blocks containing perylene labeled glucose units were added to the system and used to decorate the surface of the liposomes. Upon the binding between rhodamine labeled con A to the glucose units at the biomimetic membrane surface, a Förster resonance energy transfer system can be formed which combines unique fluorescence properties of perylene (e.g., high fluorescence quantum yield, no triplet formation) and its high hydrophobicity for efficient anchoring in membranes to form a novel probe for the investigation of sugar-driven binding reactions at biomimetic surfaces. Two glucose-labeled perylene derivatives were synthesized with different spacer length between the perylene and glucose unit in order to probe the binding of conA. The binding interaction was fully characterized by using high-end fluorescence techniques. Steady-state and time-resolved fluorescence techniques (e.g., fluorescence depolarization) in combination with single-molecule fluorescence spectroscopy techniques (fluorescence correlation spectroscopy, FCS) were used to monitor the interaction with conA. Base on the fluorescence depolarization, the rotational correlation times and the alteration in the diffusion coefficient (determined by FCS) the binding of the conA to the liposomes carrying the probe was studied. Moreover, single pair FRET experiments using pulsed interleaved excitation are used to characterize in detail the binding of conA to the liposome on a single molecule level avoiding averaging out effects.

Keywords: concanavalin A, FRET, sensor, biomimetic membrane

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Authors: L. Abubakar, B. M. Sokoto, I. U. Mohammed, M. S. Na’allah, A. Mohammad, A. N. Garba, T. S. Bubuche

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Onion (Allium cepa var. cepa L.), is the most important species of the Allium group belonging to family Alliaceae and genus Allium. It can be regarded as the single important vegetable species in the world after tomatoes. Despite the similarities, which bring the species together, the genus is a strikingly diverse one, with more than five hundred species, which are perennial and mostly bulbous plants. Out of these, only seven species are in cultivation, and five are the most important species of the cultivated Allium. However, Allium cepa (onion) and Allium sativum (Garlic) are the two major cultivated species grown all over the world of which the onion crop is the most important. Heritability defined as the proportion of the observed total variability that is genetic, and its estimates from variance components give more useful information of genotypic variation from the total phenotypic differences and environmental effects on the individuals or families. It therefore guide the breeder with respect to the ease with which selection of traits can be carried out. Heritability estimates guide the breeder with respect to ease of selection of traits while correlations suggest how selection among characters can be practiced. Correlations explain relationship between characters and suggest how selection among characters can be practiced in breeding programmes. Highly significant correlations have been reported, between yield, maturity, rings/bulb and storage loss in onions. Similarly significant positive correlation exists between total bulb yield and plant height, leaf number/plant, bulb diameter and bulb yield/plant. Moderate positive correlations have been observed between maturity date and yield, dry matter content was highly correlated with soluble solids, and higher correlations were also observed between storage loss and soluble solids. The objective of the study is to determine heritability estimates and correlations for characters among onion cultivars of North Western Nigeria. This is envisaged will assist in the breeding of superior onion cultivars within the zone. Thirteen onion cultivars were collected during an expedition covering north western Nigeria and Southern part of Niger Republic during 2013, which are areas noted for onion production. The cultivars were evaluated at two locations; Sokoto, in Sokoto State and Jega in Kebbi State all in Nigeria during the 2013/14 onion season (dry season) under irrigation. Combined analysis of the results revealed fresh bulb yield is highly significantly positively correlated with bulb height and cured bulb yield, and significant positive correlation with plant height and bulb diameter. It also recorded significant negative correlation with mean No. of leaves/plant and non significant negative correlation with bolting %. Cured bulb yield (marketable yield) had highly significant positive correlation with mean bulb weight and fresh bulb yield/ha, with significant positive correlation with bulb height. It also recorded highly significant negative correlation with No. of leaves/plant and significant negative correlation with bolting % and non significant positive correlation with plant height and non significant negative correlation with bulb diameter. High broad sense heritability estimates were recorded for plant height, fresh bulb yield, number of leaves/plant, bolting % and cured bulb yield. Medium to low broad sense heritabilities were also observed for mean bulb weight, plant height and bulb diameter.

Keywords: correlation, heritability, onions, North Western Nigeria

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Authors: J. Munuzuri, L. Onieva, J. Guadix, P. Cortes

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The aeronautical sector represents the main source of industrial development in the South of the Iberian Peninsula, with the establishment of key players like Embraer in Alentejo or Airbus in Andalusia. Subsequently, the economic promotion policies implemented in both neighbouring regions seek to consolidate a trans-border aeronautical cluster to gain critical mass and seek synergies between companies and research centres. The first step of the proposed scheme entails the identification of common interests shared by companies, technological centres and university research groups in both regions. This involves determining the specific type of activities carried out at the different companies established in the two regions (ranging from OEMs to SMEs) and also building a catalogue of available infrastructures and skills on the side of research centres and universities. The results of this first step reveal potential one-to-one partnerships, and also highlight the aggregate strengths and needs of the two regions within the aeronautical sector, taking into account both the current scenario and its expected evolution. The second step of the scheme focuses on the particularly relevant companies identified in the first step, and consists of the completion of in-depth technological audits liable to suggest potential development actions or R&D projects in those companies, counting when possible on the capabilities shown by other members of the cluster. These technological audits follow a three-round process aimed at identifying specific needs, validating those identifications and suggesting possible actions to be taken. The final objective of this methodology is to enhance the economic activity in the aeronautical sector in both regions, always with an innovative perspective. The success of the scheme should be measured in terms of partnerships created, R&D projects initiated, and spin-off companies generated.

Keywords: aeronautical sector, technological audits, technology transfer, trans-border cluster

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Authors: Ioanna Koumi

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The aim of the intervention presented is to show the positive effects a mindfulness programme can have on the behaviour of preschoolers (years 4-6). The programme was implemented as part of the psychologist's work in 5 preschool units on the Greek island of Chios. Classroom-based activities of mindfulness were shown and practiced in 5 sessions, in collaboration with teachers, in order to make preschoolers aware of how their brain affects their behaviour, as well as of how they can have more positive behaviours, especially in instances of negative feelings. The outcomes of the intervention were assessed via questionnaire completion before and after the sessions by the teachers, as well as focus groups procedures with students, teachers, and parents. Implications of how mindfulness programmes can also be implemented at home are further discussed. School year in which the programme is being implemented: 2022-23 Intervention method: based on basic mindfulness theory and practice, the 220 students (age 4-6) in 11 classes of the 5 preschools that participated were given lessons of how to become aware of their states of focusing, regulation, attention, emotional situation, as well as body and social situations. Furthermore, the preschoolers were encouraged to make more mindful choices when it came to negative situations and emotions. Assessment method: The school as a caring community Profile II – Questionnaire completed by 20 preschool teachers prior to and after the intervention, Focus group sessions with teachers, students, parents at the end of the intervention Results: the assessment will be completed in May 2023.

Keywords: preschool, mindfulness training, self-awareness, social-emotional development

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Authors: Mete Kazaz, Birol Gülnar

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Television news has gained a new dimension in terms of ideological approaches as a result of such factors as globalization, cross monopolization, presence of international companies etc. and certain strategies have been developed at the production, presentation and distribution stages of news. In this study, television news about a process called “settlement process” was investigated. In this framework, news about the settlement process on TV channels of TRT 1, ATV, FOX TV, NTV, HABERTÜRK, TRT HABER and STV was investigated using the content analysis method in terms of the strategies the ideology construction, attitude towards the party in power, attitude towards parties in opposition and attitude towards BDP (Peace and Democracy Part) and Imrali (the island where Abdullah Ocalan, head of PKK, is kept). First, the aforementioned TV channels were selected randomly from 3 groups in order to be able to reveal the representational capacity of commercial, news and public channels. The study covers 557 news items broadcast in the main news bulletins between the dates of 15 March 2013 and 15 March 2013. While there was a positive attitude towards the government in a sizable portion of the news about the settlement process (63.6%), the attitude of 25.3% of the news was impartial towards the government and 11.3% had a negative attitude. On the other hand, there was a negative attitude towards the Opposition in a considerable portion of the news about the settlement process (56.1%). The attitude of 35.9% of the news towards the Opposition was impartial whereas 8.0% had a positive attitude. While 34.9% of the news about the settlement process used the legitimization strategy from among the ideology construction strategies, 22.8% used the unification strategy, 15.7% the reification strategy, 15.6% fractional and 11% concealment/mystification strategy.

Keywords: attitude, ideological framing, television news, social sciences

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Authors: Biao Sun, Tejas Bhatelia, Vishnu Pareek, Ranjeet Utikar, Moses Tadé

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Additive manufacturing (AM), commonly known as 3D printing, with the continuing advances in parallel processing and computational modeling, has created a paradigm shift (with significant radical thinking) in the design and operation of chemical processing plants, especially LNG plants. With the rising energy demands, environmental pressures, and economic challenges, there is a continuing industrial need for disruptive technologies such as AM, which possess capabilities that can drastically reduce the cost of manufacturing and operations of chemical processing plants in the future. However, the continuing challenge for 3D printing is its lack of adaptability in re-designing the process plant equipment coupled with the non-existent theory or models that could assist in selecting the optimal candidates out of the countless potential fabrications that are possible using AM. One of the most common packings used in the LNG process is structured packing in the packed column (which is a unit operation) in the process. In this work, we present an example of an optimum strategy for the application of AM to this important unit operation. Packed columns use a packing material through which the gas phase passes and comes into contact with the liquid phase flowing over the packing, typically performing the necessary mass transfer to enrich the products, etc. Structured packing consists of stacks of corrugated sheets, typically inclined between 40-70° from the plane. Computational Fluid Dynamics (CFD) was used to test and model various geometries to study the governing hydrodynamic characteristics. The results demonstrate that the costly iterative experimental process can be minimized. Furthermore, they also improve the understanding of the fundamental physics of the system at the multiscale level. SpiroPak, patented by Curtin University, represents an innovative structured packing solution currently at a technology readiness level (TRL) of 5~6. This packing exhibits remarkable characteristics, offering a substantial increase in surface area while significantly enhancing hydrodynamic and mass transfer performance. Recent studies have revealed that SpiroPak can reduce pressure drop by 50~70% compared to commonly used commercial packings, and it can achieve 20~50% greater mass transfer efficiency (particularly in CO2 absorption applications). The implementation of SpiroPak has the potential to reduce the overall size of columns and decrease power consumption, resulting in cost savings for both capital expenditure (CAPEX) and operational expenditure (OPEX) when applied to retrofitting existing systems or incorporated into new processes. Furthermore, pilot to large-scale tests is currently underway to further advance and refine this technology.

Keywords: Additive Manufacturing (AM), 3D printing, Computational Fluid Dynamics (CFD, structured packing (SpiroPak)

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Authors: Leman Korkmaz, Bahar Bahtiyar-Saygan

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Objective: The COVID-19 pandemic has been affecting the whole world since the beginning of 2020. In addition to health-related and financial effects, there seem to be significant psychological effects as well, among them those related to people’s views and representations of marriage and divorce. Background: Although various impacts of COVID-19 have been investigated since the beginning of the pandemic, there is a limited number of studies on its effects concerning relationships. This research aims to understand how the COVID-19 pandemic affects the views on and representations of marriage and divorce by conducting two studies. Method: In the first study, one-to-one semi-structured interviews were conducted with 31 participants (20 single and 11 married individuals) to investigate their evaluations regarding the effect of COVID-19 on people’s views of marriage in general and their own views of marriage in particular. In the second study, 298 entries on the most frequently used online social platform in Turkey (EkşiSözlük) under two separate headings for COVID-19 impact on marriage and divorce were analyzed, and meaningful thematic units were formed. Results: The findings of the thematic analysis indicated that participants mostly mentioned both the positive and negative effects of COVID-19 on the views and representations of marriage. There were both common (e.g., loneliness, violence, etc.) and distinct (e.g., sexuality, positive and negative effects on attitudes towards marriage, etc.) thematic units between the results of the two studies. Implications: There are considerable implications discussed in light of the literature on Terror Management Theory, Attachment Theory, stress research, and growth perspective.

Keywords: COVID-19 pandemic, divorce, marriage, relationships, representations, views

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Authors: Akalu Banbeta, Emmanuel Lesaffre, Reynaldo Martina, Joost Van Rosmalen

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Including data from previous studies (historical data) in the analysis of the current study may reduce the sample size requirement and/or increase the power of analysis. The most common example is incorporating historical control data in the analysis of a current clinical trial. However, this only applies when the historical control dataare similar enough to the current control data. Recently, several Bayesian approaches for incorporating historical data have been proposed, such as the meta-analytic-predictive (MAP) prior and the modified power prior (MPP) both for single control as well as for multiple historical control arms. Here, we examine the performance of the MAP and the MPP approaches for the analysis of (over-dispersed) count data. To this end, we propose a computational method for the MPP approach for the Poisson and the negative binomial models. We conducted an extensive simulation study to assess the performance of Bayesian approaches. Additionally, we illustrate our approaches on an overactive bladder data set. For similar data across the control arms, the MPP approach outperformed the MAP approach with respect to thestatistical power. When the means across the control arms are different, the MPP yielded a slightly inflated type I error (TIE) rate, whereas the MAP did not. In contrast, when the dispersion parameters are different, the MAP gave an inflated TIE rate, whereas the MPP did not.We conclude that the MPP approach is more promising than the MAP approach for incorporating historical count data.

Keywords: count data, meta-analytic prior, negative binomial, poisson

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Authors: Elizaveta Korzhova, Sebastien Deon, Patrick Fievet, Dmitry Lopatin, Oleg Baranov

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Filtration with nanoporous ultrafiltration membranes is an attractive option to remove ionic pollutants from contaminated effluents. Unfortunately, commercial membranes are not necessarily suitable for specific applications, and their modification by polymer deposition is a fruitful way to adapt their performances accordingly. Many methods are usually used for surface modification, but a novel technique based on electrospray is proposed here. Various quantities of polymers were deposited on a commercial membrane, and the impact of the deposit is investigated on filtration performances and discussed in terms of charge and hydrophobicity. The electrospray deposition is a technique which has not been used for membrane modification up to now. It consists of spraying small drops of polymer solution under a high voltage between the needle containing the solution and the metallic support on which membrane is stuck. The advantage of this process lies in the small quantities of polymer that can be coated on the membrane surface compared with immersion technique. In this study, various quantities (from 2 to 40 μL/cm²) of solutions containing two charged polymers (13 mmol/L of monomer unit), namely polyethyleneimine (PEI) and polystyrene sulfonate (PSS), were sprayed on a negatively charged polyethersulfone membrane (PLEIADE, Orelis Environment). The efficacy of the polymer deposition was then investigated by estimating ion rejection, permeation flux, zeta-potential and contact angle before and after the polymer deposition. Firstly, contact angle (θ) measurements show that the surface hydrophilicity is notably improved by coating both PEI and PSS. Moreover, it was highlighted that the contact angle decreases monotonously with the amount of sprayed solution. Additionally, hydrophilicity enhancement was proved to be better with PSS (from 62 to 35°) than PEI (from 62 to 53°). Values of zeta-potential (ζ were estimated by measuring the streaming current generated by a pressure difference on both sides of a channel made by clamping two membranes. The ζ-values demonstrate that the deposits of PSS (negative at pH=5.5) allow an increase of the negative membrane charge, whereas the deposits of PEI (positive) lead to a positive surface charge. Zeta-potentials measurements also emphasize that the sprayed quantity has little impact on the membrane charge, except for very low quantities (2 μL/m²). The cross-flow filtration of salt solutions containing mono and divalent ions demonstrate that polymer deposition allows a strong enhancement of ion rejection. For instance, it is shown that rejection of a salt containing a divalent cation can be increased from 1 to 20 % and even to 35% by deposing 2 and 4 μL/cm² of PEI solution, respectively. This observation is coherent with the reversal of the membrane charge induced by PEI deposition. Similarly, the increase of negative charge induced by PSS deposition leads to an increase of NaCl rejection from 5 to 45 % due to electrostatic repulsion of the Cl- ion by the negative surface charge. Finally, a notable fall in the permeation flux due to the polymer layer coated at the surface was observed and the best polymer concentration in the sprayed solution remains to be determined to optimize performances.

Keywords: ultrafiltration, electrospray deposition, ion rejection, permeation flux, zeta-potential, hydrophobicity

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Authors: David Guillermo Piedrahita Marquez, Hector Suarez Mahecha, Jairo Humberto Lopez

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It was necessary to establish which formulation is suitable for the preservation of aquaculture products, that why edible films were made. These were to a characterization in order to meet their morphology physicochemical and mechanical properties, optical. Six Formulations of chitosan and propolis ethanolic extract encapsulated were developed because of their activity against pathogens and due to their properties, which allows the creation waterproof polymer networks against gasses, vapor, and physical damage. In the six Formulations, the concentration of comparison material (1% w/v, 2% pv) and the bioactive concentrations (0.5% w/v, 1% w/v, 1.5% pv) were changed and the results obtained were compared with statistical and multivariate analysis methods. It was observed that the matrices showed a mayor impermeability and thickness control samples and the samples reported in the literature. Also, these films showed a notorious uniformity of the films and a bigger resistance to the physical damage compared with other edible films made of other biopolymers. However the action of some compounds had a negative effect on the mechanical properties and changed drastically the optical properties, the bioactive has an effect on Polymer Matrix and it was determined that the films with 2% w / v of chitosan and 1.5% w/v encapsulated, exhibited the best properties and suffered to a lesser extent the negative impact of immiscible substances.

Keywords: chitosan, edible films, ethanolic extract of propolis, mechanical properties, optical properties, physical characterization, scanning electron microscopy (SEM)

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Authors: Nurul Hidayah, Farida Rahmatika, Fathimah Azzahra, Nesty Herennadia

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Aromatherapy candles are one of the insecticide media that have not been much researched. The active ingredient that is proven to have the effect of insecticide is a citrus extract from lemongrass oil (Cymbopogon). Aromatherapy candles are added by citrus compounds to be insecticidal for Ae. aegypti mosquito that was related to the infectious disease such as dengue fever. This research aims to find out if aromatherapy candles of citrus compounds have an insecticidal effect on Ae. aegypti mosquito. We used true experimental design including posttest only with control group design. The samples are 20 male and female Ae. aegypti mosquitos with aged 1-7 days belong to the inclusion criteria. The subjects were divided into 6 groups, consisting of 1 negative control group and 5 treatment groups with variation concentration are 1%; 2%; 3%; 4%; 5%. Each group will be treated for 2 hours and observed death after 24 hours. Replication in each group is done 4 times. The results were then tested statistically using Kruskal-Wallis and probit test. Mean of death in negative control group, and treatment group 1%; 2%; 3%; 4%; 5% respectively 0; 1; 0.25; 0; 1 and 1 mosquito. The Kruskal-Wallis test in the study group found no significant difference (p = 0.178). The probit analysis showed that LC50 and LC90 were 20.069% and 31.557%. The aromatherapy candle of a citrus compound has an insecticidal effect on the Ae aegypti mosquito.

Keywords: Ae. aegypti insecticide, aromatherapy candle, citrus compound, lemongrass oil (Cymbopogon)

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Authors: Marla Wendy Spergel

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The purpose of this qualitative study is to showcase graduated high school students’ to voice on the impact past teachers had on their motivation to learn, and if this impact has affected their post-high-school lives. Through a focus group strategy, 21 graduated high school alumni participated in three separate focus groups. Participants discussed their former teacher’s emotional intelligence skills, which influenced their motivation to learn or not. A focused review of the literature revealed that teachers are a major factor in a student’s motivation to learn. This research was guided by Bandura’s Social Cognitive Theory of Motivation and constructs related to learning and motivation from Carl Rogers’ Humanistic Views of Personality, and from Brain-Based Learning perspectives with a major focus on the area of Emotional Intelligence. Findings revealed that the majority of participants identified teachers who most motivated them to learn and demonstrated skills associated with emotional intelligence. An important and disturbing finding relates to the saliency of negative experiences. Further work is recommended to expand this line of study in Higher Education, perform a long-term study to better gain insight into long-term benefits attributable to experiencing positive teachers, study the negative impact teachers have on students’ motivation to learn, specifically focusing on student anxiety and acquired helplessness.

Keywords: emotional intelligence, learning, motivation, pedagogy

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Authors: Abdulmohsen Alruwaili

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A partial differential system featuring momentum and energy balance is often used to describe simulations of flow initiation and thermal shifting in boundary layers. The buoyancy force in terms of temperature is factored in the momentum balance equation. Buoyancy force causes the flow quantity to fluctuate along the streamwise direction 𝑋; therefore, the problem can be, to our best knowledge, analyzed through nonsimilar modeling. In this analysis, a nonsimilar model is evolved for radiative mixed convection of a magnetized power-law nanoliquid flow on top of a vertical plate installed in a stationary fluid. The upward linear stretching initiated the flow in the vertical direction. Assuming nanofluids are composite of copper (Cu) and alumina (Al₂O₃) nanoparticles, the viscous dissipation in this case is negligible. The nonsimilar system is dealt with analytically by local nonsimilarity (LNS) via numerical algorithm bvp4c. Surface temperature and flow field are shown visually in relation to factors like mixed convection, magnetic field strength, nanoparticle volume fraction, radiation parameters, and Prandtl number. The repercussions of magnetic and mixed convection parameters on the rate of energy transfer and friction coefficient are represented in tabular forms. The results obtained are compared to the published literature. It is found that the existence of nanoparticles significantly improves the temperature profile of considered nanoliquid. It is also observed that when the estimates of the magnetic parameter increase, the velocity profile decreases. Enhancement in nanoparticle concentration and mixed convection parameter improves the velocity profile.

Keywords: nanofluid, power law model, mixed convection, thermal radiation

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Authors: S. R. Santhanam

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A gifted child is one who gives evidence of creativity, good memory, rapid learning. In mathematics, a teacher often comes across some gifted children and they exhibit the following characteristics: unusual alertness, enjoying solving problems, getting bored on repetitions, self-taught, going beyond what teacher taught, ask probing questions, connecting unconnected concepts, vivid imagination, readiness for research work, perseverance of a topic. There are two main areas of research carried out on them: 1)identifying gifted children, 2) interacting and channelizing them. A lack of appropriate recognition will lead the gifted child demotivated. One of the main findings is if proper attention and nourishment are not given then it leads a gifted child to become depressed, underachieving, fail to reach their full potential and sometimes develop negative attitude towards school and study. After identifying them, a mathematics teacher has to develop them into a fall fledged achiever. The responsibility of the teacher is enormous. The teacher has to be resourceful and patient. But interacting with them one finds a lot of surprises and awesomeness. The elementary algebraic identities like (a+b)(a-b)=a²-b², expansion of like (a+b)²(a-b)² and others are taught to students, of age group 13-15 in India. An average child will be satisfied with a single proof and immediate application of these identities. But a gifted child expects more from the teacher and at one stage after a little training will surpass the teacher also. In this short paper, the author shares his experience regarding teaching algebraic identities to gifted children. The following problem was given to a set of 10 gifted children of the specified age group: If a natural number ‘n’ to expressed as the sum of the two squares, will 2n also be expressed as the sum of two squares? An investigation has been done on what multiples of n satisfying the criterion. The attempts of the gifted children were consolidated and conclusion was drawn. A second problem was given to them as: can two natural numbers be found such that the difference of their square is 3? After a successful solution, more situations were analysed. As a third question, the finding of the sign of an algebraic expression in three variables was analysed. As an example: if a,b,c are real and unequal what will be sign of a²+4b²+9c²-4ab-12bc-6ca? Apart from an expression as a perfect square what other methods can be employed to prove an algebraic expression as positive negative or non negative has been analysed. Expressions like 4x²+2y²+13y²-2xy-4yz-6zx were given, and the children were asked to find the sign of the expression for all real values of x,y and z. In all investigations, only basic algebraic identities were used. As a next probe, a divisibility problem was initiated. When a,b,c are natural numbers such that a+b+c is at least 6, and if a+b+c is divisible by 6 then will 6 divide a³+b³+c³. The gifted children solved it in two different ways.

Keywords: algebraic identities, gifted children, Indian scenario, research

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Authors: Charisse H. Tay

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Background: Schizophrenia is a severe chronic mental disorder that can result in hallucinations, delusions, reduced social engagement, and lack of motivation. While antipsychotic medications often provide the basis for treatment, psychosocial strategies complement the benefit of medications and can result in meaningful improvements in symptoms and functioning. The aim of the study was to investigate psychosocial strategies used by internet self-help forum participants to effectively manage symptoms caused by schizophrenia. Internet self-help forums are a resource for medical and psychological problems and are commonly used to share information about experiences with symptom management. Method: Three international self-help internet forums on schizophrenia were identified using a search engine. 1,181 threads regarding non-pharmacological, psychosocial self-management of schizophrenia symptoms underwent screening, resulting in the final identification and coding of 91 threads and 191 posts from 134 unique forum users that contained details on psychosocial strategies endorsed personally by users that allowed them to effectively manage symptoms of schizophrenia, including positive symptoms (e.g., auditory/visual/tactile hallucinations, delusions, paranoia), negative symptoms (e.g.., avolition, apathy, anhedonia), symptoms of distress, and cognitive symptoms (e.g., memory loss). Results: Effective symptom management strategies personally endorsed by online forum users were psychological skills (e.g., re-focusing, mindfulness/meditation, reality checking; n = 94), engaging in activities (e.g., exercise, working/volunteering, hobbies; n = 84), social/familial support (n = 48), psychotherapy (n = 33), diet (n = 18), and religion/spirituality (n = 14). 44.4% of users reported using more than one strategy to manage their symptoms. The most common symptoms targeted and effectively managed, as specified by users, were positive symptoms (n = 113), negative symptoms (n = 17), distress (n = 8), and memory loss (n = 6). 10.5% of users reported more than one symptom effectively targeted. 70.2% of users with positive symptoms reported that psychological skills were effective for symptom relief. 88% of users with negative symptoms and 75% with distress symptoms reported that engaging in activities was effective. Discussion: Individuals with schizophrenia rely on a variety of different psychosocial methods to manage their symptoms. Different symptomology appears to be more effectively targeted by different types of psychosocial strategies. This may help to inform treatment strategy and tailored for individuals with schizophrenia.

Keywords: psychosocial treatment, qualitative methods, schizophrenia, symptom management

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Authors: Abbasali Abouei Mehrizi, Hao Wang

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The thin film region is so important in heat transfer process due to its low thermal resistance. On the other hand, the dynamic contact angle is crucial boundary condition in numerical simulations. While different modeling contains different assumption of the microscopic contact angle, none of them has experimental evidence for their assumption, and the contact line movement mechanism still remains vague. The experimental investigation in complete wetting is more popular than partial wetting, especially in nanoscale resolution when there is sharp variation in thin film profile in partial wetting. In the present study, an experimental investigation of water film morphology near the triple phase contact line during the condensation is performed. The state-of-the-art tapping-mode atomic force microscopy (TM-AFM) was used to get the high-resolution film profile goes down to 2 nm from the contact line. The droplet was put in saturated chamber. The pristine silicon wafer was used as a smooth substrate. The substrate was heated by PI film heater. So the chamber would be over saturated by droplet evaporation. By turning off the heater, water vapor gradually started condensing on the droplet and the droplet advanced. The advancing speed was less than 20 nm/s. The dominant results indicate that in contrast to nonvolatile liquid, the film profile goes down straightly to the surface till 2 nm from the substrate. However, small bending has been observed below 20 nm, occasionally. So, it can be claimed that for the low condensation rate the microscopic contact angle equals to the optically detectable macroscopic contact angle. This result can be used to simplify the heat transfer modeling in partial wetting. The experimental result of the equality of microscopic and macroscopic contact angle can be used as a solid evidence for using this boundary condition in numerical simulation.

Keywords: advancing, condensation, microscopic contact angle, partial wetting

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Authors: L. S. Zavodna, J. Zavodny Pospisil

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The aim of this paper is to identify the factors for sustainability in the accommodation sector. Although sustainability is a current trend in tourism, not many facilities know how to apply the concept in practice. This paper presents a model for the implementation of sustainability in hotels, hostels, campgrounds, or other facilities. First, there are identified sections of each accommodation facility, which can contribute to sustainability. Furthermore, concrete steps are presented to transfer this model into reality.

Keywords: accommodation sector, model, sustainable tourism, sustainability

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Authors: Ravi Raj, Louis Chiu, Deepak Marla, Aijun Huang

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Hybridization of the directed laser deposition (DLD) process using an in-situ micro-roller to impart a vertical compressive load on the deposited bead at elevated temperatures can relieve tensile residual stresses incurred in the process. To investigate this stress relief mechanism and its relationship with the in-situ rolling parameters, a fully coupled dynamic thermo-mechanical model is presented in this study. A single bead deposition of Ti-6Al-4V alloy with an in-situ roller made of mild steel moving at a constant speed with a fixed nominal bead reduction is simulated using the explicit solver of the finite element software, Abaqus. The thermal model includes laser heating during the deposition process and the heat transfer between the roller and the deposited bead. The laser heating is modeled using a moving heat source with a Gaussian distribution, applied along the pre-formed bead’s surface using the VDFLUX Fortran subroutine. The bead’s cross-section is assumed to be semi-elliptical. The interfacial heat transfer between the roller and the bead is considered in the model. Besides, the roller is cooled internally using axial water flow, considered in the model using convective heat transfer. The mechanical model for the bead and substrate includes the effects of rolling along with the deposition process, and their elastoplastic material behavior is captured using the J2 plasticity theory. The model accounts for strain, strain rate, and temperature effects on the yield stress based on Johnson-Cook’s theory. Various aspects of this material behavior are captured in the FE software using the subroutines -VUMAT for elastoplastic behavior, VUHARD for yield stress, and VUEXPAN for thermal strain. The roller is assumed to be elastic and does not undergo any plastic deformation. Also, contact friction at the roller-bead interface is considered in the model. Based on the thermal results of the bead, the distance between the roller and the deposition nozzle (roller o set) can be determined to ensure rolling occurs around the beta-transus temperature for the Ti-6Al-4V alloy. It is identified that roller offset and the nominal bead height reduction are crucial parameters that influence the residual stresses in the hybrid process. The results obtained from a simulation at roller offset of 20 mm and nominal bead height reduction of 7% reveal that the tensile residual stresses decrease to about 52% due to in-situ rolling throughout the deposited bead. This model can be used to optimize the rolling parameters to minimize the residual stresses in the hybrid DLD process with in-situ micro-rolling.

Keywords: directed laser deposition, finite element analysis, hybrid in-situ rolling, thermo-mechanical model

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Authors: Walid A. Attia, Taher M. Bazan, Fawzy Eltohamy, Mahmoud Fathy

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System performance evaluation is an essential stage in the design of high-resolution satellite telescopes prior to the development process. In this paper, a system performance evaluation of a very high-resolution satellite telescope is investigated. The evaluated system has a Korsch optical scheme design. This design has been discussed in another paper with respect to three-mirror anastigmat (TMA) scheme design and the former configuration showed better results. The investigated system is based on the Korsch optical design integrated with a time-delay and integration charge coupled device (TDI-CCD) sensor to achieve a ground sampling distance (GSD) of 25 cm. The key performance metrics considered are the spatial resolution, the signal to noise ratio (SNR) and the total modulation transfer function (MTF) of the system. In addition, the national image interpretability rating scale (NIIRS) metric is assessed to predict the image quality according to the modified general image quality equation (GIQE). Based on the orbital, optical and detector parameters, the estimated GSD is found to be 25 cm. The SNR has been analyzed at different illumination conditions of target albedos, sun and sensor angles. The system MTF has been computed including diffraction, aberration, optical manufacturing, smear and detector sampling as the main contributors for evaluation the MTF. Finally, the system performance evaluation results show that the computed MTF value is found to be around 0.08 at the Nyquist frequency, the SNR value was found to be 130 at albedo 0.2 with a nadir viewing angles and the predicted NIIRS is in the order of 6.5 which implies a very good system image quality.

Keywords: modulation transfer function, national image interpretability rating scale, signal to noise ratio, satellite telescope performance evaluation

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Authors: Dibyendu Das, Santanu Kumar Pal

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Milk protein lactoferrin (Lf) exhibits potent antibacterial activity due to its interaction with Gram-negative bacterial cell membrane component, lipopolysaccharide (LPS). This paper represents fabrication of new Liquid crystals (LCs) based biosensors to explore the interaction between Lf and LPS. LPS self-assembled at aqueous/LCs interface and orients interfacial nematic 4-cyano-4’- pentylbiphenyl (5CB) LCs in a homeotropic fashion (exhibiting dark optical image under polarized optical microscope). Interestingly, on the exposure of Lf on LPS decorated aqueous/LCs interface, an optical image of LCs changed from dark to bright indicating an ordering alteration of interfacial LCs from homeotropic to tilted/planar state. The ordering transition reflects strong binding between Lf and interfacial LPS that, in turn, perturbs the orientation of LCs. With the help of epifluorescence microscopy, we further affirmed the interfacial LPS-Lf binding event by imaging the presence of FITC tagged Lf at the LPS laden aqueous/LCs interface. Finally, we have investigated the conformational behavior of Lf in solution as well as in the presence of LPS using Circular Dichroism (CD) spectroscopy and further reconfirmed with Vibrational Circular Dichroism (VCD) spectroscopy where we found that Lf undergoes alpha-helix to random coil-like structure in the presence of LPS. As a whole the entire results described in this paper establish a robust approach to envisage the interaction between LPS and Lf through the ordering transitions of LCs at aqueous/LCs interface.

Keywords: endotoxin, interface, lactoferrin, lipopolysaccharide

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Authors: Parvaneh Eskandari, Rachel O'Reilly

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In the last years, controlling the self-assembly behavior of stimuli-responsive nano-objects, including micelles, vesicles, worm-like, etc., at different conditions is considered a pertinent challenge in the polymer community. The aim of the project was to synthesize aggregation-induced emission (AIE)-active stimuli-responsive polymeric nano-objects to control the self-assemblies morphologies of the prepared nano-objects. Two types of nanoobjects, micelle and vesicles, including PDMAEMA-b-P(BzMA-TPEMA) [PDMAEMA: poly(N,Ndimethylaminoethyl methacrylate); P(BzMA-TPEMA): poly[benzyl methacrylate-co- tetraphenylethene methacrylate]] were synthesized by using reversible addition−fragmentation chain-transfer (RAFT)- mediated polymerization-induced self-assembly (PISA), which combines polymerization and self-assembly in a single step. Transmission electron microscope and dynamic light scattering (DLS) analysis were used to confirm the formed self-assemblies morphologies. The controlled self-assemblies were applied as nitrophenolic compounds (NPCs) adsorbents from wastewater, thanks to their CO2-responsive part, PDMAEMA. Moreover, the fluorescence-active part of the prepared nano-objects, P(BzMA-TPEMA), played a key role in the detection of the NPCs at the aqueous solution. The optical properties of the prepared nano-objects were studied by UV/Vis and fluorescence spectroscopies. For responsivity investigations, the hydrodynamic diameter and Zeta-potential (ζ-potential) of the sample's aqueous solution were measured by DLS. In the end, the prepared nano-objects were used for the detection and adsorption of different NPCs.

Keywords: aggregation-induced emission polymers, stimuli-responsive polymers, reversible addition−fragmentation chain-transfer polymerization, polymerization-induced self-assembly, wastewater treatment

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Authors: Mati Ullah, Shams Ur Rahman

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The purpose of this research study is to investigate the effect of macroeconomic and bank-specific factors on credit risk in Islamic banking in Pakistan. The future of financial institutions largely depends on how well they manage risks. Credit risk is an important type of risk affecting the banking sector. The current study has taken quarterly data for the period of 6 years, from 1st July 2014 to 30 Jun 2020. The data set consisted of secondary data. Data was extracted from the websites of the State Bank and World Bank and from the financial statements of the concerned banks. In this study, the Ordinary least square model was used for the analysis of the data. The results supported the hypothesis that macroeconomic factors and bank-specific factors have a significant effect on credit risk. Macroeconomic variables, Inflation and exchange rates have positive significant effects on credit risk. However, gross domestic product has a negative significant relationship with credit risk. Moreover, the corporate rate has no significant relation with credit risk. Internal variables, size, management efficiency, net profit share income and capital adequacy have been proven to influence positively and significantly the credit risk. However, loan to deposit-has a negative insignificance relationship with credit risk. The contribution of this article is that similar conclusions have been made regarding the influence of banking factors on credit risk.

Keywords: credit risk, Islamic banks, macroeconomic variables, banks specific variable

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Authors: Adeel Zulifqar, Hong Hu

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Auxetic fabrics are a special kind of textile materials which possess negative Poisson’s ratio. Opposite to most of the conventional fabrics, auxetic fabrics get bigger in the transversal direction when stretched or get smaller when compressed. Auxetic fabrics are superior to conventional fabrics because of their counterintuitive properties, such as enhanced porosity under the extension, excellent formability to a curved surface and high energy absorption ability. Up till today, auxetic fabrics have been produced based on two approaches. The first approach involves using auxetic fibre or yarn and weaving technology to fabricate auxetic fabrics. The other method to fabricate the auxetic fabrics is by using non-auxetic yarns. This method has gained extraordinary curiosity of researcher in recent years. This method is based on realizing auxetic geometries into the fabric structure. In the woven fabric structure auxetic geometries can be realized by creating a differential shrinkage phenomenon into the fabric structural unit cell. This phenomenon can be created by using loose and tight weave combinations within the unit cell of interlacement pattern along with elastic and non-elastic yarns. Upon relaxation, the unit cell of interlacement pattern acquires a non-uniform shrinkage profile due to different shrinkage properties of loose and tight weaves in designed pattern, and the auxetic geometry is realized. The development of uni-stretch auxetic woven fabrics and bi-stretch auxetic woven fabrics by using this method has already been reported. This study reports the development of another kind of bi-stretch auxetic woven fabric. The fabric is first designed by transforming the auxetic geometry into interlacement pattern and then fabricated, using the available conventional weaving technology and non-auxetic elastic and non-elastic yarns. The tensile tests confirmed that the developed bi-stretch auxetic woven fabrics exhibit negative Poisson’s ratio over a wide range of tensile strain. Therefore, it can be concluded that the auxetic geometry can be realized into the woven fabric structure by creating the phenomenon of differential shrinkage and bi-stretch woven fabrics made of non-auxetic yarns having auxetic behavior and stretchability are possible can be obtained. Acknowledgement: This work was supported by the Research Grants Council of Hong Kong Special Administrative Region Government (grant number 15205514).

Keywords: auxetic, differential shrinkage, negative Poisson's ratio, weaving, stretchable

Procedia PDF Downloads 151

Authors: Musaab Mohammed Ahmed Ali, Vladimir Vodichev

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work deals with an universal control technique or single controller for linear and nonlinear stabilization and tracing control systems. These systems may be structured as SISO and MIMO. Parameters of controlled plants can vary over a wide range. Introduced a novel control systems design method, construction of stable platform orbits using derivative balance, solved transfer function stability preservation problem of linear system under partial substitution of a rational function. Universal controller is proposed as a polar system with the multiple orbits to simplify design procedure, where each orbit represent single order of controller transfer function. Designed controller consist of proportional, integral, derivative terms and multiple feedback and feedforward loops. The controller parameters synthesis method is presented. In generally, controller parameters depend on new polynomial equation where all parameters have a relationship with each other and have fixed values without requirements of retuning. The simulation results show that the proposed universal controller can stabilize infinity number of linear and nonlinear plants and shaping desired previously ordered performance. It has been proven that sensor errors and poor performance will be completely compensated and cannot affect system performance. Disturbances and noises effect on the controller loop will be fully rejected. Technical and economic effect of using proposed controller has been investigated and compared to adaptive, predictive, and robust controllers. The economic analysis shows the advantage of single controller with fixed parameters to drive infinity numbers of plants compared to above mentioned control techniques.

Keywords: derivative balance, fixed parameters, stable platform, universal control

Procedia PDF Downloads 136

Authors: Sukru Dursun, Zeynep Cansu Ayturan, Mostafa Maroof

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Metal coating which is important method used for protecting metals against oxidation and corrosion, decreasing friction, protecting metals from chemicals, easing cleaning of the metals. There are several methods used for metal coating such as hot-dip galvanizing, thermal spraying, electroplating and sherardizing. Method which will be used for metal coating depends on the type of metal. The materials mostly used for coating are zinc, nickel, brass, chrome, gold, cadmium, copper, brass, and silver. Within these materials, chrome ion has significant negative impacts on human, other living organisms and environment. Moreover, especially on human chrome may cause lung cancer, stomach ulcer, kidney and liver function disorders and death. Therefore, wastewaters of metal coating industry including chrome should be treated very carefully. In this study, wastewater containing chrome produced by metal coating industry was analysed with phytotoxicity method that is based on measuring the reaction of some plant species against different concentrations of chrome solution. Main plants used for phytotoxicity tests are Lepidium sativum and Lemna minor. Owing to phytotoxicity test, assessing the negative effects of chrome which may harm plants and offering more accurate wastewater treatment techniques against chromium wastewater is possible. Furthermore, the results taken from phytotoxicity tests were analysed with respect to their variance and their importance against different concentrations of chrome solution were determined.

Keywords: metal coating wastewater, chrome, phytotoxicity, Lepidium sativum, Lemna minor

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Authors: Thomas Wimmer, Bernhard Weigand

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The improvement of gas turbine efficiency is one of the main drivers of research and development in the gas turbine market. This has led to elevated gas turbine inlet temperatures beyond the melting point of the utilized materials. The turbine parts need to be actively cooled in order to withstand these harsh environments. However, the usage of compressor air as coolant decreases the overall gas turbine efficiency. Thus, coolant consumption needs to be minimized in order to gain the maximum advantage from higher turbine inlet temperatures. Therefore, sophisticated cooling designs for gas turbine parts aim to minimize coolant mass flow. New design space is accessible as additive manufacturing is maturing to industrial usage for the creation of hot gas flow path parts. By making use of this technology more efficient cooling schemes can be manufacture. In order to find such cooling schemes a generative design method is being developed. It generates cooling schemes randomly which adhere to a set of rules. These assure the sanity of the design. A huge amount of different cooling schemes are generated and implemented in a simulation environment where it is validated. Criteria for the fitness of the cooling schemes are coolant mass flow, maximum temperature and temperature gradients. This way the whole design space is sampled and a Pareto optimum front can be identified. This approach is applied to a flat plate, which resembles a simplified section of a hot gas flow path part. Realistic boundary conditions are applied and thermal barrier coating is accounted for in the simulation environment. The resulting cooling schemes are presented and compared to representative conventional cooling schemes. Further development of this method can give access to cooling schemes with an even better performance having higher complexity, which makes use of the available design space.

Keywords: additive manufacturing, cooling, gas turbine, heat transfer, heat transfer design, optimization

Procedia PDF Downloads 352