Search results for: free market
3081 Induced Thermo-Osmotic Convection for Heat and Mass Transfer
Authors: Francisco J. Arias
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Consideration is given to a mechanism of heat and mass transport in solutions similar than that of natural convection but with one important difference. Here the mechanism is not promoted by density differences in the fluid occurring due to temperature gradients (coefficient of thermal expansion) but rather by solubility differences due to the thermal dependence of the solubility (coefficient of thermal solubility). Utilizing a simplified physical model, it is shown that by the proper choice of the concentration of a given solution, convection might be induced by the alternating precipitation of the solute -when the solution becomes supersaturated, and its posterior recombination when changes in temperature occurs. The spontaneous change in the Gibbs free energy during the mixing is the driven force for the mechanism. The maximum extractable energy from this new type of thermal convection was derived. Experimental data from a closed-loop circuit was obtained demonstrating the feasibility for continuous separation and recombination of the solution. This type of heat and mass transport -which doesn’t depend on gravity, might potentially be interesting for heat and mass transport downwards (as in solar-roof collectors to inside homes), horizontal (e.g., microelectronic applications), and in microgravity (space technology). Also, because the coefficient of thermal solubility could be positive or negative, the investigated thermo-osmosis convection can be used either for heating or cooling.Keywords: natural convection, thermal gradient, solubility, osmotic pressure
Procedia PDF Downloads 2943080 Experiences of Discrimination and Coping Strategies of Second Generation Academics during the Career-Entry Phase in Austria
Authors: R. Verwiebe, L. Seewann, M. Wolf
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This presentation addresses marginalization and discrimination as experienced by young academics with a migrant background in the Austrian labor market. Focusing on second generation academics of Central Eastern European and Turkish descent we explore two major issues. First, we ask whether their career-entry and everyday professional life entails origin-specific barriers. As educational residents, they show competences which, when lacking, tend to be drawn upon to explain discrimination: excellent linguistic skills, accredited high-level training, and networks. Second, we concentrate on how this group reacts to discrimination and overcomes experiences of marginalization. To answer these questions, we utilize recent sociological and social psychological theories that focus on the diversity of individual experiences. This distinguishes us from a long tradition of research that has dealt with the motives that inform discrimination, but has less often considered the effects on those concerned. Similarly, applied coping strategies have less often been investigated, though they may provide unique insights into current problematic issues. Building upon present literature, we follow recent discrimination research incorporating the concepts of ‘multiple discrimination’, ‘subtle discrimination’, and ‘visual social markers’. 21 problem-centered interviews are the empirical foundation underlying this study. The interviewees completed their entire educational career in Austria, graduated in different universities and disciplines and are working in their first post-graduate jobs (career entry phase). In our analysis, we combined thematic charting with a coding method. The results emanating from our empirical material indicated a variety of discrimination experiences ranging from barely perceptible disadvantages to directly articulated and overt marginalization. The spectrum of experiences covered stereotypical suppositions at job interviews, the disavowal of competencies, symbolic or social exclusion by new colleges, restricted professional participation (e.g. customer contact) and non-recruitment due to religious or ethnical markers (e.g. headscarves). In these experiences the role of the academics education level, networks, or competences seemed to be minimal, as negative prejudice on the basis of visible ‘social markers’ operated ‘ex-ante’. The coping strategies identified in overcoming such barriers are: an increased emphasis on effort, avoidance of potentially marginalizing situations, direct resistance (mostly in the form of verbal opposition) and dismissal of negative experiences by ignoring or ironizing the situation. In some cases, the academics drew into their specific competences, such as an intellectual approach of studying specialist literature, focus on their intercultural competences or planning to migrate back to their parent’s country of origin. Our analysis further suggests a distinction between reactive (i.e. to act on and respond to experienced discrimination) and preventative strategies (applied to obviate discrimination) of coping. In light of our results, we would like to stress that the tension between educational and professional success experienced by academics with a migrant background – and the barriers and marginalization they continue to face – are essential issues to be introduced to socio-political discourse. It seems imperative to publicly accentuate the growing social, political and economic significance of this group, their educational aspirations, as well as their experiences of achievement and difficulties.Keywords: coping strategies, discrimination, labor market, second generation university graduates
Procedia PDF Downloads 2213079 A New Phenolic Compound Isolated from Laurus nobilis from Lebanon and Comparison of Antioxidant Activity of Different Parts
Authors: Turk Ayman, Ahn Jong Hoon, Khalife K. Hala, Gali-Muhtasib Hala, Lee Mi Kyeong
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Laurus nobilis is an aromatic plant widely distributed in the Mediterranean region. The leaves of this plant are frequently used as a spice and as a traditional medicine for several diseases. In our present study, the methanolic extract of L. nobilis leaves showed antioxidant activity. Chromatographic separations of the EtOAc fraction which had the highest antioxidant activity led to the isolation of 12 compounds. Among them, there was a new phenylpropanoid derivative, which was identified by 1D and 2D NMR experiments, as well as high resolution mass spectrometry. In addition, two major compounds, catechin and epicatechin, which showed strong antioxidant activity may be responsible for the antioxidant activity of L. nobilis leaves. Since different plant parts may contain different types of constituents which contribute to the biological activities, we investigated the antioxidant activity of different parts of L. nobilis such as leaves, stems and fruits. Stems of L. nobilis showed the most potent antioxidant activity, followed by leaves. Further quantitation of total phenol and flavonoids contents revealed a positive correlation between the content of these compounds and antioxidant activity. Taken together, phenolic compounds including flavonoids are responsible for antioxidant activity of L. nobilis. In addition, stem parts of L. nobilis are suggested as good sources for antioxidant activity. Conclusively, L. nobilis might be effective in several free radical mediated diseases.Keywords: antioxidant activity, different parts, Laurus nobilis, phenolic compound
Procedia PDF Downloads 3073078 Self-Carried Theranostic Nanoparticles for in vitro and in vivo Cancer Therapy with Real-Time Monitoring of Drug Release
Authors: Jinfeng Zhang, Chun-Sing Lee
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The use of different nanocarriers for delivering hydrophobic pharmaceutical agents to tumor sites has garnered major attention. Despite the merits of these nanocarriers, further studies are needed for improving their drug loading capacities (typically less than 10%) and reducing their potential systemic toxicity. So development of alternative self-carried nanodrug delivery strategies without using any inert carriers is highly desirable. In this study, we developed a self-carried theranostic curcumin (Cur) nanodrug for highly effective cancer therapy in vitro and in vivo with real-time monitoring of drug release. With a biocompatible C18PMH-PEG functionalization, the Cur nanoparticles (NPs) showed excellent dispersibility and outstanding stability in physiological environment, with drug loading capacity higher than 78 wt.%. Both confocal microscopy and flow cytometry confirmed the cellular fluorescent “OFF-ON” activation and real-time monitoring of Cur molecule release, showing its potential for cancer diagnosis. In vitro and in vivo experiments clearly show that therapeutic efficacy of the PEGylated Cur NPs is much better than that of free Cur. This self-carried theranostic strategy with real-time monitoring of drug release may open a new way for simultaneous cancer therapy and diagnosis.Keywords: drug delivery, in vitro and in vivo cancer therapy, real-time monitoring, self-carried
Procedia PDF Downloads 3993077 Short Review on Models to Estimate the Risk in the Financial Area
Authors: Tiberiu Socaciu, Tudor Colomeischi, Eugenia Iancu
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Business failure affects in various proportions shareholders, managers, lenders (banks), suppliers, customers, the financial community, government and society as a whole. In the era in which we have telecommunications networks, exists an interdependence of markets, the effect of a failure of a company is relatively instant. To effectively manage risk exposure is thus require sophisticated support systems, supported by analytical tools to measure, monitor, manage and control operational risks that may arise. As we know, bankruptcy is a phenomenon that managers do not want no matter what stage of life is the company they direct / lead. In the analysis made by us, by the nature of economic models that are reviewed (Altman, Conan-Holder etc.), estimating the risk of bankruptcy of a company corresponds to some extent with its own business cycle tracing of the company. Various models for predicting bankruptcy take into account direct / indirect aspects such as market position, company growth trend, competition structure, characteristics and customer retention, organization and distribution, location etc. From the perspective of our research we will now review the economic models known in theory and practice for estimating the risk of bankruptcy; such models are based on indicators drawn from major accounting firms.Keywords: Anglo-Saxon models, continental models, national models, statistical models
Procedia PDF Downloads 4053076 Bayesian Value at Risk Forecast Using Realized Conditional Autoregressive Expectiel Mdodel with an Application of Cryptocurrency
Authors: Niya Chen, Jennifer Chan
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In the financial market, risk management helps to minimize potential loss and maximize profit. There are two ways to assess risks; the first way is to calculate the risk directly based on the volatility. The most common risk measurements are Value at Risk (VaR), sharp ratio, and beta. Alternatively, we could look at the quantile of the return to assess the risk. Popular return models such as GARCH and stochastic volatility (SV) focus on modeling the mean of the return distribution via capturing the volatility dynamics; however, the quantile/expectile method will give us an idea of the distribution with the extreme return value. It will allow us to forecast VaR using return which is direct information. The advantage of using these non-parametric methods is that it is not bounded by the distribution assumptions from the parametric method. But the difference between them is that expectile uses a second-order loss function while quantile regression uses a first-order loss function. We consider several quantile functions, different volatility measures, and estimates from some volatility models. To estimate the expectile of the model, we use Realized Conditional Autoregressive Expectile (CARE) model with the bayesian method to achieve this. We would like to see if our proposed models outperform existing models in cryptocurrency, and we will test it by using Bitcoin mainly as well as Ethereum.Keywords: expectile, CARE Model, CARR Model, quantile, cryptocurrency, Value at Risk
Procedia PDF Downloads 1093075 A Quantitative Case Study Analysis of Store Format Contributors to U.S. County Obesity Prevalence in Virginia
Authors: Bailey Houghtaling, Sarah Misyak
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Food access; the availability, affordability, convenience, and desirability of food and beverage products within communities, is influential on consumers’ purchasing and consumption decisions. These variables may contribute to lower dietary quality scores and a higher obesity prevalence documented among rural and disadvantaged populations in the United States (U.S.). Current research assessing linkages between food access and obesity outcomes has primarily focused on distance to a traditional grocery/supermarket store as a measure of optimality. However, low-income consumers especially, including U.S. Department of Agriculture’s Supplemental Nutrition Assistance Program (SNAP) participants, seem to utilize non-traditional food store formats with greater frequency for household dietary needs. Non-traditional formats have been associated with less nutritious food and beverage options and consumer purchases that are high in saturated fats, added sugars, and sodium. Authors’ formative research indicated differences by U.S. region and rurality in the distribution of traditional and non-traditional SNAP-authorized food store formats. Therefore, using Virginia as a case study, the purpose of this research was to determine if a relationship between store format, rurality, and obesity exists. This research applied SNAP-authorized food store data (food access points for SNAP as well as non-SNAP consumers) and obesity prevalence data by Virginia county using publicly available databases: (1) SNAP Retailer Locator, and; (2) U.S. County Health Rankings. The alpha level was set a priori at 0.05. All Virginia SNAP-authorized stores (n=6,461) were coded by format – grocery, drug, mass merchandiser, club, convenience, dollar, supercenter, specialty, farmers market, independent grocer, and non-food store. Simple linear regression was applied primarily to assess the relationship between store format and obesity. Thereafter, multiple variables were added to the regression to account for potential moderating relationships (e.g., county income, rurality). Convenience, dollar, non-food or restaurant, mass merchandiser, farmers market, and independent grocer formats were significantly, positively related to obesity prevalence. Upon controlling for urban-rural status and income, results indicated the following formats to be significantly related to county obesity prevalence with a small, positive effect: convenience (p=0.010), accounting for 0.3% of the variance in obesity prevalence; dollar (p=0.005; 0.5% of the variance), and; non-food (p=0.030; 1.3% of the variance) formats. These results align with current literature on consumer behavior at non-traditional formats. For example, consumers’ food and beverage purchases at convenience and dollar stores are documented to be high in saturated fats, added sugars, and sodium. Further, non-food stores (i.e., quick-serve restaurants) often contribute to a large portion of U.S. consumers’ dietary intake and thus poor dietary quality scores. Current food access research investigates grocery/supermarket access and obesity outcomes. These results suggest more research is needed that focuses on non-traditional food store formats. Nutrition interventions within convenience, dollar, and non-food stores, for example, that aim to enhance not only healthy food access but the affordability, convenience, and desirability of nutritious food and beverage options may impact obesity rates in Virginia. More research is warranted utilizing the presented investigative framework in other U.S. and global regions to explore the role and the potential of non-traditional food store formats to prevent and reduce obesity.Keywords: food access, food store format, non-traditional food stores, obesity prevalence
Procedia PDF Downloads 1433074 Effect of Atmospheric Turbulence on Hybrid FSO/RF Link Availability under Qatar's Harsh Climate
Authors: Abir Touati, Syed Jawad Hussain, Farid Touati, Ammar Bouallegue
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Although there has been a growing interest in the hybrid free-space optical link and radio frequency FSO/RF communication system, the current literature is limited to results obtained in moderate or cold environment. In this paper, using a soft switching approach, we investigate the effect of weather inhomogeneities on the strength of turbulence hence the channel refractive index under Qatar harsh environment and their influence on the hybrid FSO/RF availability. In this approach, either FSO/RF or simultaneous or none of them can be active. Based on soft switching approach and a finite state Markov Chain (FSMC) process, we model the channel fading for the two links and derive a mathematical expression for the outage probability of the hybrid system. Then, we evaluate the behavior of the hybrid FSO/RF under hazy and harsh weather. Results show that the FSO/RF soft switching renders the system outage probability less than that of each link individually. A soft switching algorithm is being implemented on FPGAs using Raptor code interfaced to the two terminals of a 1Gbps/100 Mbps FSO/RF hybrid system, the first being implemented in the region. Experimental results are compared to the above simulation results.Keywords: atmospheric turbulence, haze, hybrid FSO/RF, outage probability, refractive index
Procedia PDF Downloads 4193073 Service Information Integration Platform as Decision Making Tools for the Service Industry Supply Chain-Indonesia Service Integration Project
Authors: Haikal Achmad Thaha, Pujo Laksono, Dhamma Nibbana Putra
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Customer service is one of the core interest in a service sector of a company, whether as the core business or as service part of the operation. Most of the time, the people and the previous research in service industry is focused on finding the best business model solution for the service sector, usually to decide between total in house customer service, outsourcing, or something in between. Conventionally, to take this decision is some important part of the management job, and this is a process that usually takes some time and staff effort, meanwhile market condition and overall company needs may change and cause loss of income and temporary disturbance in the companies operation . However, in this paper we have offer a new concept model to assist decision making process in service industry. This model will featured information platform as central tool to integrate service industry operation. The result is service information model which would ideally increase response time and effectivity of the decision making. it will also help service industry in switching the service solution system quickly through machine learning when the companies growth and the service solution needed are changing.Keywords: service industry, customer service, machine learning, decision making, information platform
Procedia PDF Downloads 6223072 Modeling Anisotropic Damage Algorithms of Metallic Structures
Authors: Bahar Ayhan
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The present paper is concerned with the numerical modeling of the inelastic behavior of the anisotropically damaged ductile materials, which are based on a generalized macroscopic theory within the framework of continuum damage mechanics. Kinematic decomposition of the strain rates into elastic, plastic and damage parts is basis for accomplishing the structure of continuum theory. The evolution of the damage strain rate tensor is detailed with the consideration of anisotropic effects. Helmholtz free energy functions are constructed separately for the elastic and inelastic behaviors in order to be able to address the plastic and damage process. Additionally, the constitutive structure, which is based on the standard dissipative material approach, is elaborated with stress tensor, a yield criterion for plasticity and a fracture criterion for damage besides the potential functions of each inelastic phenomenon. The finite element method is used to approximate the linearized variational problem. Stress and strain outcomes are solved by using the numerical integration algorithm based on operator split methodology with a plastic and damage (multiplicator) variable separately. Numerical simulations are proposed in order to demonstrate the efficiency of the formulation by comparing the examples in the literature.Keywords: anisotropic damage, finite element method, plasticity, coupling
Procedia PDF Downloads 2063071 Public-Private Partnership in Tourism Development: Kuwait Experience within 2035 Vision
Authors: Obaid Alotaibi
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Tourism and recreation have become one of the important and influential sectors in most of the modern economies. This sector has been accepted as one of the alternative sources of national income, employment, and foreign exchange. Kuwait has many potentialities in tourism and recreation, and exploitation of this leads to more diversification of the economy besides augmenting its contribution to the GDP. It is an import-oriented economy; it requires hard currencies (foreign exchange) to meet the import costs as well as to maintain stability in the international market. To compensate for the revenue fall stemmed from fluctuations in oil prices -where the agriculture, fisheries, and industrial sectors are too immune and inelastic- the only alternative solution is the regeneration of the tourism and recreation to surface. This study envisages the characteristics of tourism and recreation, the economic and social importance for the society, the physical and human endowments, as well as the tourist pattern and plans for promoting and sustaining tourism in the country. The study summarizes many recommendations, including the necessity of establishing authority or a council for tourism, linking the planning of tourism development with the comprehensive planning for economic and social development in Kuwait in the shadow of 2035 vision, and to encourage the investors to develop new tourist and recreation projects.Keywords: Kuwait, public-private, partnership, tourism, 2035 vision
Procedia PDF Downloads 1283070 Impact Analysis of Cultivation of Jatropha Tree on Fuel Prices and Environment
Authors: Saba Arif, Anam Nadeem, Roman Kalvin, Muzaffar Ali, Burhan Ali, Juntakan Taweekun
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Globally transportation sector accounts for around 25% of energy demand and nearly 62% of oil consumed. Therefore, new energy sources are required to introduce for this huge demand replenishment of depleting conventional energy sources. Currently, biofuels such as Jatropha trees as an energy carrier for transportation sector are being utilized effectively round the globe. However, climate conditions at low altitudes with an average annual temperature above 20 degrees Celsius and rainfall of 300-1000mm are considered the most suitable environment for the efficient growth of Jatropha trees. The current study is providing a theoretical survey-based analysis to investigate the effect of rate of cultivation of jatropha trees on the reduction of fuel prices and its environmental benefits. The resulted study shows that jatropha tree’s 100 kg seeds give 80kg oil and the conversion process cost is very small as 890 PKR. Moreover, the extraction of oil from Jatropha tree is tax-free compared to other fuels. The analysis proved very essential for potential assessment of Jatropha regarding future energy fuel for transportation sector at global level. Additionally, it can be very beneficial for increment in the total amount of transportation fuel in Pakistan.Keywords: jatropha tree, environmental impact, energy contents, theoretical survey
Procedia PDF Downloads 2193069 Design of Raw Water Reservoir on Sandy Soil
Authors: Venkata Ramana Pamu
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This paper is a case study of a 5310 ML capacity Raw Water Reservoir (RWR), situated in Indian state Rajasthan, which is a part of Rajasthan Rural Water Supply & Fluorosis Mitigation Project. This RWR embankment was constructed by locally available material on natural ground profile. Height of the embankment was varying from 2m to 10m.This is due to existing ground level was varying. Reservoir depth 9m including 1.5m free board and 1V:3H slopes were provided both upstream and downstream side. Proper soil investigation, tests were done and it was confirmed that the existing soil is sandy silt. The existing excavated earth was used as filling material for embankment construction, due to this controlling seepage from upstream to downstream be a challenging task. Slope stability and Seismic analysis of the embankment done by Conventional method for both full reservoir condition and rapid drawdown. Horizontal filter at toe level was provided along with upstream side PCC (Plain Cement Concrete) block and HDPE (High Density poly ethylene) lining as a remedy to control seepage. HDPE lining was also provided at storage area of the reservoir bed level. Mulching was done for downstream side slope protection.Keywords: raw water reservoir, seepage, seismic analysis, slope stability
Procedia PDF Downloads 4973068 Consumer Perception of 3D Body Scanning While Online Shopping for Clothing
Authors: A. Grilec, S. Petrak, M. Mahnic Naglic
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Technological development and the globalization in production and sales of clothing in the last decade have significantly influenced the changes in consumer relationship with the industrial-fashioned apparel and in the way of clothing purchasing. The Internet sale of clothing is in a constant and significant increase in the global market, but the possibilities offered by modern computing technologies in the customization segment are not yet fully involved, especially according to the individual customer requirements and body sizes. Considering the growing trend of online shopping, the main goal of this paper is to investigate the differences in customer perceptions towards online apparel shopping and particularly to discover the main differences in perceptions between customers regarding three different body sizes. In order to complete the research goal, the quantitative study on the sample of 85 Croatian consumers was conducted in 2017 in Zagreb, Croatia. Respondents were asked to indicate their level of agreement according to a five-point Likert scale ranging from strongly disagree (1) to strongly agree (5). To analyze attitudes of respondents, simple and descriptive statistics were used. The main findings highlight the differences in respondent perception of 3D body scanning, using 3D body scanning in Internet shopping, online apparel shopping habits regarding their body sizes.Keywords: consumer behavior, Internet, 3D body scanning, body types
Procedia PDF Downloads 1633067 Developing House’s Model to Assess the Translation of Key Cultural Texts
Authors: Raja Al-Ghamdi
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This paper aims to systematically assess the translation of key cultural texts. The paper, therefore, proposes a modification of the discourse analysis model for translation quality assessment introduced by the linguist Juliane House (1977, 1997, 2015). The data for analysis has been chosen from a religious text that has never been investigated before. It is an overt translation of the biography of Prophet Mohammad. The book is written originally in Arabic and translated into English. A soft copy of the translation, entitled The Sealed Nectar, is posted on numerous websites including the Internet Archive library which offers a free access to everyone. The text abounds with linguistic and cultural phenomena relevant to Islamic and Arab lingua-cultural context which make its translation a challenge, as well as its assessment. Interesting findings show that (1) culturemes are rich points and both the translator’s subjectivity and intervention are apparent in mediating them, (2) given the nature of historical narration, the source text reflects the author’s positive shading, whereas the target text reflects the translator’s axiological orientation as neutrally shaded, and, (3) linguistic gaps, metaphorical expressions and intertextuality are major stimuli to compensation strategies.Keywords: Arabic-English discourse analysis, key cultural texts, overt translation, quality assessment
Procedia PDF Downloads 2823066 Volatility and Stylized Facts
Authors: Kalai Lamia, Jilani Faouzi
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Measuring and controlling risk is one of the most attractive issues in finance. With the persistence of uncontrolled and erratic stocks movements, volatility is perceived as a barometer of daily fluctuations. An objective measure of this variable seems then needed to control risks and cover those that are considered the most important. Non-linear autoregressive modeling is our first evaluation approach. In particular, we test the presence of “persistence” of conditional variance and the presence of a degree of a leverage effect. In order to resolve for the problem of “asymmetry” in volatility, the retained specifications point to the importance of stocks reactions in response to news. Effects of shocks on volatility highlight also the need to study the “long term” behaviour of conditional variance of stocks returns and articulate the presence of long memory and dependence of time series in the long run. We note that the integrated fractional autoregressive model allows for representing time series that show long-term conditional variance thanks to fractional integration parameters. In order to stop at the dynamics that manage time series, a comparative study of the results of the different models will allow for better understanding volatility structure over the Tunisia stock market, with the aim of accurately predicting fluctuation risks.Keywords: asymmetry volatility, clustering, stylised facts, leverage effect
Procedia PDF Downloads 2993065 A Study of Transferable Strategies in Multilanguage Learning
Authors: Zixi You
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With the demand of multilingual speakers increasing in the job market, multi-language learning programs have become more and more popular among undergraduate students. A study on multi-language learning strategies is therefore highly demanded on both practical and theoretical levels. Based on previous classification of learning strategies in SLA, and an investigation of BA Modern Language program students (with post-A level L2 and ab initio L3 learning experience from year one), this study explores and compares different types of learning strategies used by multi-language speakers and learners, transferable learning strategies between L2 and L3, and factors affecting the transfer. The results indicate that all the 23 types of learning strategies of L2 are employed when learning L3 from ab initio level, yet with different tendencies. Learning strategy transfer from L2 to L3 (i.e., the learners attribute the applying of these L3 learning strategies to be a direct result of their L2 learning experience) are observed in all 23 types of learning strategies. Comparatively, six types of “cognitive strategies” have higher transfer tendency than others. With regard to the failure of the transfer of some particular L2 strategies and the development of independent L3 strategies of individual learners, factors such as language proficiency, language typology and learning environment have played important roles among others. The presentation of this study will provide audiences with detailed data, insightful analysis and discussion on both theoretical and practical aspects of multi-language learning that will benefit both students and educators.Keywords: learning strategy, multi-language acquisition, second language acquisition, strategy transfer
Procedia PDF Downloads 5753064 Difference between 'HDR Ir-192 and Co-60 Sources' for High Dose Rate Brachytherapy Machine
Authors: Md Serajul Islam
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High Dose Rate (HDR) Brachytherapy is used for cancer patients. In our country’s prospect, we are using only cervices and breast cancer treatment by using HDR. The air kerma rate in air at a reference distance of less than a meter from the source is the recommended quantity for the specification of gamma ray source Ir-192 in brachytherapy. The absorbed dose for the patients is directly proportional to the air kerma rate. Therefore the air kerma rate should be determined before the first use of the source on patients by qualified medical physicist who is independent from the source manufacturer. The air kerma rate will then be applied in the calculation of the dose delivered to patients in their planning systems. In practice, high dose rate (HDR) Ir-192 afterloader machines are mostly used in brachytherapy treatment. Currently, HDR-Co-60 increasingly comes into operation too. The essential advantage of the use of Co-60 sources is its longer half-life compared to Ir-192. The use of HDRCo-60 afterloading machines is also quite interesting for developing countries. This work describes the dosimetry at HDR afterloading machines according to the protocols IAEA-TECDOC-1274 (2002) with the nuclides Ir-192 and Co-60. We have used 3 different measurement methods (with a ring chamber, with a solid phantom and in free air and with a well chamber) in dependence of each of the protocols. We have shown that the standard deviations of the measured air kerma rate for the Co-60 source are generally larger than those of the Ir-192 source. The measurements with the well chamber had the lowest deviation from the certificate value. In all protocols and methods, the deviations stood for both nuclides by a maximum of about 1% for Ir-192 and 2.5% for Co-60-Sources respectively.Keywords: Ir-192 source, cancer, patients, cheap treatment cost
Procedia PDF Downloads 2363063 Comparison of Real-Time PCR and FTIR with Chemometrics Technique in Analysing Halal Supplement Capsules
Authors: Mohd Sukri Hassan, Ahlam Inayatullah Badrul Munir, M. Husaini A. Rahman
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Halal authentication and verification in supplement capsules are highly required as the gelatine available in the market can be from halal or non-halal sources. It is an obligation for Muslim to consume and use the halal consumer goods. At present, real-time polymerase chain reaction (RT-PCR) is the most common technique being used for the detection of porcine and bovine DNA in gelatine due to high sensitivity of the technique and higher stability of DNA compared to protein. In this study, twenty samples of supplements capsules from different products with different Halal logos were analyzed for porcine and bovine DNA using RT-PCR. Standard bovine and porcine gelatine from eurofins at a range of concentration from 10-1 to 10-5 ng/µl were used to determine the linearity range, limit of detection and specificity on RT-PCR (SYBR Green method). RT-PCR detected porcine (two samples), bovine (four samples) and mixture of porcine and bovine (six samples). The samples were also tested using FT-IR technique where normalized peak of IR spectra were pre-processed using Savitsky Golay method before Principal Components Analysis (PCA) was performed on the database. Scores plot of PCA shows three clusters of samples; bovine, porcine and mixture (bovine and porcine). The RT-PCR and FT-IR with chemometrics technique were found to give same results for porcine gelatine samples which can be used for Halal authentication.Keywords: halal, real-time PCR, gelatine, chemometrics
Procedia PDF Downloads 2413062 Evaluation Of In Vitro Antioxidant Potential of Camellia Sinensis Leaves Extract
Authors: Jirathan Pongchababnapa
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Polyphenols are the most common antioxidant found in plants and are efficient in capturing oxidative free radicals. Antioxidants are substances found in medicinal plants which may have a protective role to play in certain conditions such as heart disease, stroke and some cancers. By relying on these benefits, we have traced out the presence of antioxidant in Camellia sinensis leaves extract. This study aims to evaluate flavonoids content in C. sinensisextract and investigate antioxidant activities by using DPPH and ABTS radical scavenging capacity assay. The total flavonoid content of C. Sinensis extract was determined and expressed as quercetin equivalents (QE)/g measured by the aluminum chloride colorimetric method. The results showed that the IC₅₀ of C. Sinensis leaves extract were 40.90 μg/mL ± 0.755 and32.96 μg/mL ± 0.679 for DPPH and ABTS, respectively. C. Sinensis extract at increasing concentration showed antioxidant activities as a concentration dependent manner. In the DPPH assay, vitamin C was used as a positive control, whereas Trolox was used as a positive control in the ABTS assay. In conclusion, C. Sinensis extract consisted of a high amount of flavonoids content which possesses potent antioxidant activity. However, further investigation on the identification of pure compound of this plant and molecular antioxidant assays are still required.Keywords: ABTS assay, antioxidant, camellia sinensis, DPPH assay, total flavonoid content
Procedia PDF Downloads 2103061 Numerical Simulation of Natural Gas Dispersion from Low Pressure Pipelines
Authors: Omid Adibi, Nategheh Najafpour, Bijan Farhanieh, Hossein Afshin
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Gas release from the pipelines is one of the main factors in the gas industry accidents. Released gas ejects from the pipeline as a free jet and in the growth process, the fuel gets mixed with the ambient air. Accordingly, an accidental spark will release the chemical energy of the mixture with an explosion. Gas explosion damages the equipment and endangers the life of staffs. So due to importance of safety in gas industries, prevision of accident can reduce the number of the casualties. In this paper, natural gas leakages from the low pressure pipelines are studied in two steps: 1) the simulation of mixing process and identification of flammable zones and 2) the simulation of wind effects on the mixing process. The numerical simulations were performed by using the finite volume method and the pressure-based algorithm. Also, for the grid generation the structured method was used. The results show that, in just 6.4 s after accident, released natural gas could penetrate to 40 m in vertical and 20 m in horizontal direction. Moreover, the results show that the wind speed is a key factor in dispersion process. In fact, the wind transports the flammable zones into the downstream. Hence, to improve the safety of the people and human property, it is preferable to construct gas facilities and buildings in the opposite side of prevailing wind direction.Keywords: flammable zones, gas pipelines, numerical simulation, wind effects
Procedia PDF Downloads 1663060 Chemical Characterization of Octopus Vulgaris Ink and Evaluation of its in-vitro Antioxidant, Antimicrobial, and Anti-Schistosomicidal Activities
Authors: Salwa A. H. Hamdi, Maha A. M. El-Shazly, Mona Fathi Fol, Hanan S. Mossalem, Mosad A. Ghareeb, Amina M. Ibrahim
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One of the most distinctive and defining features of cephalopods squid, cuttlefish, and Octopus is their inking behavior. Their ink, which is blackened by melanin but also contains other constituents, has been used by humans in various ways for millennia. The present study aims to investigate the chemical profiling of the Octopus vulgaris ink extract and to evaluate its antioxidant, antimicrobial, and anti-schistosomal activities. The present results showed that GC-MS examination of Octopus vulgaris ink comprises 21 compounds. The main detected compounds are (E)-1, 2, 3, 4-Tetra (4-phenylphenyl)-2-butene-1,4-dione, Lipo-3-episapelin A, and 5,10-Dihexyltetrabenzoporphyrin. Results showed that the octopus ink had antioxidant capacity and the capability to mask DPPH free radicals in comparison with ascorbic acid. Octopus Vulgaris ink extract had inhibitory action against three gram-positive bacteria, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis, and three gram-negative bacteria, Neisseria gonorrhoeae, Escherichia coli, and Pseudomonas aeuroginosa. Additionally, the extracted ink revealed antifungal activity against Aspergillus flavus and yeast as Candida albicans. The obtained data indicated the effectiveness of ink extract in pharmaceutical industries as an antioxidant, antimicrobial and antischistosomicidalKeywords: antimicrobial, antioxidant, ink, octopus vulgaris
Procedia PDF Downloads 953059 Combining Chiller and Variable Frequency Drives
Authors: Nasir Khalid, S. Thirumalaichelvam
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In most buildings, according to US Department of Energy Data Book, the electrical consumption attributable to centralized heating and ventilation of air- condition (HVAC) component can be as high as 40-60% of the total electricity consumption for an entire building. To provide efficient energy management for the market today, researchers are finding new ways to develop a system that can save electrical consumption of buildings even more. In this concept paper, a system known as Intelligent Chiller Energy Efficiency (iCEE) System is being developed that is capable of saving up to 25% from the chiller’s existing electrical energy consumption. In variable frequency drives (VFDs), research has found significant savings up to 30% of electrical energy consumption. Together with the VFDs at specific Air Handling Unit (AHU) of HVAC component, this system will save even more electrical energy consumption. The iCEE System is compatible with any make, model or age of centrifugal, rotary or reciprocating chiller air-conditioning systems which are electrically driven. The iCEE system uses engineering principles of efficiency analysis, enthalpy analysis, heat transfer, mathematical prediction, modified genetic algorithm, psychometrics analysis, and optimization formulation to achieve true and tangible energy savings for consumers.Keywords: variable frequency drives, adjustable speed drives, ac drives, chiller energy system
Procedia PDF Downloads 5583058 Study of Functional Relevant Conformational Mobility of β-2 Adrenoreceptor by Means of Molecular Dynamics Simulation
Authors: G. V. Novikov, V. S. Sivozhelezov, S. S. Kolesnikov, K. V. Shaitan
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The study reports about the influence of binding of orthosteric ligands as well as point mutations on the conformational dynamics of β-2-adrenoreceptor. Using molecular dynamics simulation we found that there was a little fraction of active states of the receptor in its apo (ligand free) ensemble corresponded to its constitutive activity. Analysis of MD trajectories indicated that such spontaneous activation of the receptor is accompanied by the motion in intracellular part of its alpha-helices. Thus receptor’s constitutive activity directly results from its conformational dynamics. On the other hand the binding of a full agonist resulted in a significant shift of the initial equilibrium towards its active state. Finally, the binding of the inverse agonist stabilized the receptor in its inactive state. It is likely that the binding of inverse agonists might be a universal way of constitutive activity inhibition in vivo. Our results indicate that ligand binding redistribute pre-existing conformational degrees of freedom (in accordance to the Monod-Wyman-Changeux-Model) of the receptor rather than cause induced fit in it. Therefore, the ensemble of biologically relevant receptor conformations is encoded in its spatial structure, and individual conformations from that ensemble might be used by the cell in conformity with the physiological behaviour.Keywords: seven-transmembrane receptors, constitutive activity, activation, x-ray crystallography, principal component analysis, molecular dynamics simulation
Procedia PDF Downloads 2573057 A Collaborative Learning Model in Engineering Science Based on a Cyber-Physical Production Line
Authors: Yosr Ghozzi
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The Cyber-Physical Systems terminology has been well received by the industrial community and specifically appropriated in educational settings. Indeed, our latest educational activities are based on the development of experimental platforms on an industrial scale. In fact, we built a collaborative learning model because of an international market study that led us to place ourselves at the heart of this technology. To align with these findings, a competency-based approach study was conducted, and program content was revised by reflecting the projectbased approach. Thus, this article deals with the development of educational devices according to a generated curriculum and specific educational activities while respecting the repository of skills adopted from what constitutes the educational cyber-physical production systems and the laboratories that are compliant and adapted to them. The implementation of these platforms was systematically carried out in the school's workshops spaces. The objective has been twofold, both research and teaching for the students in mechatronics and logistics of the electromechanical department. We act as trainers and industrial experts to involve students in the implementation of possible extension systems around multidisciplinary projects and reconnect with industrial projects for better professional integration.Keywords: education 4.0, competency-based learning, teaching factory, project-based learning, cyber-physical systems, industry 4.0
Procedia PDF Downloads 1073056 Impact of Working Capital Management Strategies on Firm's Value and Profitability
Authors: Jonghae Park, Daesung Kim
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The impact of aggressive and conservative working capital‘s strategies on the value and profitability of the firms has been evaluated by applying the panel data regression analysis. The control variables used in the regression models are natural log of firm size, sales growth, and debt. We collected a panel of 13,988 companies listed on the Korea stock market covering the period 2000-2016. The major findings of this study are as follow: 1) We find a significant negative correlation between firm profitability and the number of days inventory (INV) and days accounts payable (AP). The firm’s profitability can also be improved by reducing the number of days of inventory and days accounts payable. 2) We also find a significant positive correlation between firm profitability and the number of days accounts receivable (AR) and cash ratios (CR). In other words, the cash is associated with high corporate profitability. 3) Tobin's analysis showed that only the number of days accounts receivable (AR) and cash ratios (CR) had a significant relationship. In conclusion, companies can increase profitability by reducing INV and increasing AP, but INV and AP did not affect corporate value. In particular, it is necessary to increase CA and decrease AR in order to increase Firm’s profitability and value.Keywords: working capital, working capital management, firm value, profitability
Procedia PDF Downloads 1893055 The Circularity of Re-Refined Used Motor Oils: Measuring Impacts and Ensuring Responsible Procurement
Authors: Farah Kanani
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Blue Tide Environmental is a company focused on developing a network of used motor oil recycling facilities across the U.S. They initiated the redesign of its recycling plant in Texas, and aimed to establish an updated carbon footprint of re-refined used motor oils compared to an equivalent product derived from virgin stock that is not re-refined. The aim was to quantify emissions savings of a circular alternative to conventional end-of-life combustion of used motor oil (UMO). To do so, they mandated an ISO-compliant carbon footprint, utilizing complex models requiring geographical and temporal accuracy to accommodate the U.S. refinery market. The quantification of linear and circular flows, proxies for fuel substitution and system expansion for multi-product outputs were all critical methodological choices and were tested through sensitivity analyses. The re-refined system consisted of continuous recycling of UMO and thus, end-of-life is considered non-existent. The unique perspective to this topic will be from a life cycle i.e. holistic one and essentially demonstrate using this example of how a cradle-to-cradle model can be used to quantify a comparative carbon footprint. The intended audience is lubricant manufacturers as the consumers, motor oil industry professionals and other industry members interested in performing a cradle-to-cradle modeling.Keywords: circularity, used motor oil, re-refining, systems expansion
Procedia PDF Downloads 313054 The Impact of the Saudi New E-Commerce Law on Protecting E-Commerce Investments in Saudi Arabia
Authors: Faris Algarni
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The Kingdom of Saudi Arabia adopted a new law of e-commerce on July 10, 2019, which is the first Saudi law regarding e-commerce. The practice of e-commerce has been started in Saudi Arabia a few years ago with no specific rules to govern e-commerce in the Kingdom. The adoption of the law raises the concern of the ability of the law to provide real protection to both the investors and the customers. Based on that, this article seeks to respond to some questions related to the protection of investors of e-commerce in Saudi Arabia, using a quantitative method through questionnaires to gather primary data. The study tried to find the impact of adopting a new Saudi law of e-commerce on the protection of the investors from the point of view of those investors. By answering this main question, this article provides an answer to the question of whether there is a need to reform the Saudi law of e-commerce to convince existing and potential foreign investors to invest in the Kingdom through e-commerce. Questions were put to the respondents to determine their level of satisfaction with the Saudi law of e-commerce and what reforms to that system would enhance the attractiveness of the Kingdom as an investment environment for e-commerce investors, based on the information gathered and the analysis of them. A key finding is that the law of e-commerce is a core factor in the decision of investors to continue investing in the e-commerce market in Saudi Arabia. A subsequent finding is that some of the respondents are not fully satisfied with the new law and think that the law provides more protection to the customers than the investors. So, they are suggesting some legal reforms to be implemented in the bylaw of e-commerce, which is not adopted yet in order to attract them to continue investing in the Kingdom.Keywords: e-commerce, law, investors, protection, Saudi Arabia
Procedia PDF Downloads 1293053 Physicochemical, Heavy Metals Analysis of Some Multi-Floral Algerian Honeys
Authors: Assia Amri, Naima Layachi, Ali Ladjama
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The characterization of some Algerian honey was carried out on the basis of their physico-chemical properties: moisture,hydroxy methyl furfural, diastase activity, pH,free, total and lactonic acidity, electrical conductivity, minerals and proline content. Studied samples are found to be low in moisture and therefore safe from fermentation, low in HMF level and high in diastase activity. Additionally the diastase activity and the HMF content are widely recognized parameters indicating the freshness of honey. Phenolic compounds present in honey are classified into two groups - simple phenols and polyphenols. The simple phenols in honey are various phenol acids, but polyphenols are various flavonoids and flavonides. The aim of our work was to determine antioxidant properties of various Algerian honey samples–the total phenol content, total flavonoids content, as well as honey anti radical activity.The quality of honey samples differs on account of various factors such as season, packaging and processing conditions, floral source, geographical origin and storage period. It is important that precautions should be taken to ensure standardization and rationalization of beekeeping techniques, manufacturing procedures and storing processes to improve honey quality.Keywords: honey, physico-chemical characterization, phenolic coumpound, HMF, diastase activity
Procedia PDF Downloads 4233052 A Multivariate 4/2 Stochastic Covariance Model: Properties and Applications to Portfolio Decisions
Authors: Yuyang Cheng, Marcos Escobar-Anel
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This paper introduces a multivariate 4/2 stochastic covariance process generalizing the one-dimensional counterparts presented in Grasselli (2017). Our construction permits stochastic correlation not only among stocks but also among volatilities, also known as co-volatility movements, both driven by more convenient 4/2 stochastic structures. The parametrization is flexible enough to separate these types of correlation, permitting their individual study. Conditions for proper changes of measure and closed-form characteristic functions under risk-neutral and historical measures are provided, allowing for applications of the model to risk management and derivative pricing. We apply the model to an expected utility theory problem in incomplete markets. Our analysis leads to closed-form solutions for the optimal allocation and value function. Conditions are provided for well-defined solutions together with a verification theorem. Our numerical analysis highlights and separates the impact of key statistics on equity portfolio decisions, in particular, volatility, correlation, and co-volatility movements, with the latter being the least important in an incomplete market.Keywords: stochastic covariance process, 4/2 stochastic volatility model, stochastic co-volatility movements, characteristic function, expected utility theory, verication theorem
Procedia PDF Downloads 152