Search results for: anisotropic elastic media
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3833

Search results for: anisotropic elastic media

1223 Good Banks, Bad Banks, and Public Scrutiny: The Determinants of Corporate Social Responsibility in Times of Financial Volatility

Authors: A. W. Chalmers, O. M. van den Broek

Abstract:

This article examines the relationship between the global financial crisis and corporate social responsibility activities of financial services firms. It challenges the general consensus in existing studies that firms, when faced with economic hardship, tend to jettison CSR commitments. Instead, and building on recent insights into the institutional determinants of CSR, it is argued that firms are constrained in their ability to abandon CSR by the extent to which they are subject to intense public scrutiny by regulators and the news media. This argument is tested in the context of the European sovereign debt crisis drawing on a unique dataset of 170 firms in 15 different countries over a six-year period. Controlling for a battery of alternative explanations and comparing financial service providers to firms operating in other economic sectors, results indicate considerable evidence supporting the main argument. Rather than abandoning CSR during times of economic hardship, financial industry firms ramp up their CSR commitments in order to manage their public image and foster public trust in light of intense public scrutiny.

Keywords: corporate social responsibility (CSR), public scrutiny, global financial crisis, financial services firms

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1222 Comparative Evaluation of Kinetic Model of Chromium and Lead Uptake from Aqueous Solution by Activated Balanitesaegyptiaca Seeds

Authors: Mohammed Umar Manko

Abstract:

A series of batch experiments were conducted in order to investigate the feasibility of Balanitesaegyptiaca seeds based activated carbon as compared with industrial activated carbon for the removal of chromium and lead ions from aqueous solution by the adsorption process within 30 to 150 minutes contact time. The activated samples were prepared using zinc chloride and tetraoxophophate(VI) acid. The results obtained showed that the activated carbon of Balanitesaegyptiaca seeds studied had relatively high adsorption capacities for these heavy metal ions compared with industrial Activated Carbon. The percentage removal of Cr (VI) and lead (II) ions by the three activated carbon samples were 64%, 70% and 71%; 60%, 66% and 60% respectively. Adsorption equilibrium was established in 90 minutes for the heavy metal ions. The equilibrium data fitted the pseudo second order out of the pseudo first, pseudo second, Elovich ,Natarajan and Khalaf models tested. The investigation also showed that the adsorbents can effectively remove metal ions from similar wastewater and aqueous media.

Keywords: activated carbon, pseudo second order, chromium, lead, Elovich model

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1221 Numerical Study of Heat Transfer in Silica Aerogel

Authors: Amal Maazoun, Abderrazak Mezghani, Ali Ben Moussa

Abstract:

Aerogel consists of a ramified and inter-connected solid skeleton enclosing a very important number of nano-sized pores filled with air that occupies most of the volume and makes very low density. The thermal conductivity of this material can reach lower values than those of any other material, and it changes with the type of the aerogel and its composition. So, in order to explain the causes of the super-insulation of our material and to determine the factors in which depends on its conductivity we used a numerical simulation. We have developed a numerical code that generates random fractal structure of silica aerogel with pre-defined concentration, properties of the backbone and the gas in the pores as well as the size of the particles. The calculation of the conductivity at any point of domain shows that it is not constant and that it depends on the pore size and the location in the pore. A numerical method based on resolution by inversion of block tridiagonal matrices is used to calculate the equivalent thermal conductivity of the whole fractal structure. The average conductivity calculated for each concentration is in good agreement with those of typical aerogels. And we found that the equivalent thermal conductivity of a silica aerogel depends strongly not only on the porosity but also on the tortuosity of the solid backbone.

Keywords: aerogel, fractal structure, numerical study, porous media, thermal conductivity

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1220 Evaluation of Affecting Factors on Effectiveness of Animal Artificial Insemination Training Courses in Zanjan Province

Authors: Ali Ashraf Hamedi Oghul Beyk

Abstract:

This research is aimed in order to demonstrate the factors affecting on effectiveness of animal artificial insemination training courses in Zanjan province. The research method is descriptive and correlation. Research tools a questionnaire and research sample are 104 persons who participated in animal artificial insemination training courses. The data resulted from this procedure was analysed by using SPSS software under windows system.independent variables include :individual, sociological, technical, and organizational, dependent variable is: affecting factors on effectiveness of animal artificial insemination training courses the finding of this study indicates that there is a significant correlation(99/0) between individual variables such as motivation and interest and experiment and effectiveness of animal artificial insemination training courses. There is significant correlation (95/0) between sociological variables such as job and education and effectiveness of animal artificial insemination training course. There is significant correlation (99/0) between techn ical variables such as training quality media and instructional materials. Moreover, effectiveness of animal artificial insemination training course there is significant correlation(0/95) between organizational variables such as trainers combination,place conditions.

Keywords: animal artificial insemination, effect, effectiveness, training courses, Zanjan

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1219 Theoretical Analysis and Numerical Evaluation of the Flow inside the Supersonic Nozzle for Chemical Lasers

Authors: Mohammedi Ferhate, Hakim Chadli, Laggoun Chaouki

Abstract:

The main objectives of work in this area are, first, obtaining the high laser energies in short time durations needed for the feasibility studies of laser induced thermodynamically exothermic chemical reactions , second, investigating the physical principles that can be used to make laser sources capable of delivering high average powers. We note that, in order to reach both objectives, one has to convert electrical or chemical energy into laser energy, using dense gaseous media.. We present results from the early development of an F atom source appropriate for HF and DF chemical laser research. We next explain the very important difficulties encountered in working with dense gases for that purpose, and we shall describe how, especially at Evaluation of downstream-mixing scheme –levels transitions (001) → (100) and (001) → (020) gas dynamic laser The physical phenomena that control the operation of presently existing laser devices are now sufficiently well understood, so that it is possible to predict that new generations of lasers could be designed in the future. The proposed model of excitation and relaxation levels was finally proved by the computational numerical code of Matlab toolboxes of different parameters of nozzle.

Keywords: hydrogen, combust, chemical laser, halogen atom

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1218 Short Text Classification for Saudi Tweets

Authors: Asma A. Alsufyani, Maram A. Alharthi, Maha J. Althobaiti, Manal S. Alharthi, Huda Rizq

Abstract:

Twitter is one of the most popular microblogging sites that allows users to publish short text messages called 'tweets'. Increasing the number of accounts to follow (followings) increases the number of tweets that will be displayed from different topics in an unclassified manner in the timeline of the user. Therefore, it can be a vital solution for many Twitter users to have their tweets in a timeline classified into general categories to save the user’s time and to provide easy and quick access to tweets based on topics. In this paper, we developed a classifier for timeline tweets trained on a dataset consisting of 3600 tweets in total, which were collected from Saudi Twitter and annotated manually. We experimented with the well-known Bag-of-Words approach to text classification, and we used support vector machines (SVM) in the training process. The trained classifier performed well on a test dataset, with an average F1-measure equal to 92.3%. The classifier has been integrated into an application, which practically proved the classifier’s ability to classify timeline tweets of the user.

Keywords: corpus creation, feature extraction, machine learning, short text classification, social media, support vector machine, Twitter

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1217 Evaluating Antifungal Potential of Respiratory Inhibitors against Phyto-Pathogenic Fungi

Authors: Sehrish Iftikhar, Ahmad Ali Shahid, Kiran Nawaz, Waheed Anwar

Abstract:

Discovery and development of new compounds require intense studies in chemistry, biochemistry. Numerous experiments under laboratory-, greenhouse- and field conditions can be performed to select suitable candidates and to understand their full potential. Novel fungicides are fundamental to combat plant diseases. Fusarium solani is important plant pathogen. New broad spectrum foliar fungicides against complex II were designed in this study. Complex II, namely succinate dehydrogenase (SDH), or succinate quinone oxidoreductase (SQR) is a multi-subunit enzyme at the crossroads of TCA and ETC at the inner mitochondrial membrane. The need for new and innovative fungicides is driven by resistance management, regulatory hurdles and increasing customer expectations amongst others. Fungicidal activity was assessed for the effect on mycelial growth and spore germination of the fungi using fungicide amended media assay. In mycelial growth assay compounds C10 and C6 were highly active against all the isolates. The compounds C1 and C10 were found most potent in spore germination test. It fully proved that the SDHIs designed in this paper displayed as good inhibitory effects against Fusarium solani.

Keywords: Wilt, Fusarium, SDH, antifungal

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1216 Eros and Postmodern Nihilism in Don Delillo’s Zero K (2016): A Psychoanalytical Reading

Authors: Nouioua Wafa

Abstract:

It is broadly accepted that the existence of postmodern individuals is distinguished by a predominant presence of skepticism, anxiety and loneliness. This social unrest is the consequence of a drastic shift in how reality and meaning are conceived, which has been replaced by something that is referred to in media theory and criticism as hyperreality. The purpose of this paper is to investigate the hyperreality that exists in the postmodern nihilistic American community that Don Delillo depicts in Zero K (2016) through the use of Jean Baudrillard's notions of Simulacra and Simulations. It is a troubled technological late capitalist society obsessed with immortality and fear of demise, and ergo it is an appropriate reading to implement Sigmund Freud’s theory of life drive (Eros), which refers to the life instinct fundamental to all humans and the urge to support productivity and construction. The results obtained from a qualitative analysis of Zero K indicate the presence of a clash between the character’s life drive and fear of mortality. In an effort to escape loneliness and death, the character Ross Lockhart undergoes, after a moment of hesitation, cryonic freezing in the convergence to preserve his life as well as that of his wife Artis, yet his son Jeffery is firmly convinced of the uselessness of combating the inevitable death.

Keywords: Don DeLillo, Eros, postmodernism Nihilism, Zero K

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1215 Eros and Postmodern Nihilism in Don Delillo’s Zero K (2016): A Psychoanalytical Reading

Authors: Wafa Nouioua

Abstract:

It is broadly accepted that the existence of postmodern individuals is distinguished by a predominant presence of skepticism, anxiety and loneliness. This social unrest is the consequence of a drastic shift in how reality and meaning are conceived, which has been replaced by something that is referred to in media theory and criticism as hyperreality. The purpose of this paper is to investigate the hyperreality that exists in the postmodern nihilistic American community that Don Delillo depicts in Zero K (2016) through the use of Jean Baudrillard notions of Simulacra and Simulations. It is a troubled technological late capitalist society obsessed with immortality and fear of demise, ergo it is an appropriate reading to implement Sigmund Freud’s theory of life drive (Eros), which refers to the life instinct fundamental to all humans and the urge to support productivity and construction. The results obtained from a qualitative analysis of Zero K indicate the presence of a clash between the character’s life drive and fear of mortality. In an effort to escape loneliness and death, the character Ross Lockhart undergoes, after a moment of hesitation, cryonic freezing in the convergence to preserve his life as well as that of his wife Artis, yet his son Jeffery is firmly convinced of the uselessness of combating the inevitable death.

Keywords: Don Dellilo, Eros, Postmodernism Nihilism, Zero K

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1214 Iron Oxide Nanoparticles: Synthesis, Properties, and Environmental Application

Authors: Shalini Rajput, Dinesh Mohan

Abstract:

Water is the most important and essential resources for existing of life on the earth. Water quality is gradually decreasing due to increasing urbanization and industrialization and various other developmental activities. It can pose a threat to the environment and public health therefore it is necessary to remove hazardous contaminants from wastewater prior to its discharge to the environment. Recently, magnetic iron oxide nanoparticles have been arise as significant materials due to its distinct properties. This article focuses on the synthesis method with a possible mechanism, structure and application of magnetic iron oxide nanoparticles. The various characterization techniques including X-ray diffraction, transmission electron microscopy, scanning electron microscopy with energy dispersive X-ray, Fourier transform infrared spectroscopy and vibrating sample magnetometer are useful to describe the physico-chemical properties of nanoparticles. Nanosized iron oxide particles utilized for remediation of contaminants from aqueous medium through adsorption process. Due to magnetic properties, nanoparticles can be easily separate from aqueous media. Considering the importance and emerging trend of nanotechnology, iron oxide nanoparticles as nano-adsorbent can be of great importance in the field of wastewater treatment.

Keywords: nanoparticles, adsorption, iron oxide, nanotechnology

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1213 Mirror-Like Effect Based on Correlations among Atoms

Authors: Qurrat-ul-Ain Gulfam, Zbigniew Ficek

Abstract:

The novel idea to use single atoms as highly reflecting mirrors has recently gained much attention. Usually, to observe the reflective nature of an atom, it is required to couple the atom to an external medium such that a directional spontaneous emission could be realized. We propose an alternative way to achieve the directional emission by considering a system of correlated atoms in free space. It is well known that mutually interacting atoms have a strong tendency to emit the radiation along particular discrete directions. That relieves one from the stingy condition of associating the atomic system to another media and facilitates the experimental implementation to a large degree. Moreover, realistic 3-dimensional collective emission can be taken into account in the dynamics. Two interesting spatial setups have been considered; one where a probe atom is confined in a linear cavity formed by two atomic mirrors and, the other where a probe atom faces a chain of correlated atoms. We observe an evidence of the mirror-like effect in a simple system of a chain of three atoms. The angular distribution of the radiation intensity observed in the far field is greatly affected by the atomic interactions. Hence, suitable directions for enhanced reflectivity can be determined.

Keywords: atom-mirror effect, correlated system, dipole-dipole interactions, intensity

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1212 A QoE-driven Cross-layer Resource Allocation Scheme for High Traffic Service over Open Wireless Network Downlink

Authors: Liya Shan, Qing Liao, Qinyue Hu, Shantao Jiang, Tao Wang

Abstract:

In this paper, a Quality of Experience (QoE)-driven cross-layer resource allocation scheme for high traffic service over Open Wireless Network (OWN) downlink is proposed, and the related problem about the users in the whole cell including the users in overlap region of different cells has been solved.A method, in which assess models of the BestEffort service and the no-reference assess algorithm for video service are adopted, to calculate the Mean Opinion Score (MOS) value for high traffic service has been introduced. The cross-layer architecture considers the parameters in application layer, media access control layer and physical layer jointly. Based on this architecture and the MOS value, the Binary Constrained Particle Swarm Optimization (B_CPSO) algorithm is used to solve the cross-layer resource allocation problem. In addition,simulationresults show that the proposed scheme significantly outperforms other schemes in terms of maximizing average users’ MOS value for the whole system as well as maintaining fairness among users.

Keywords: high traffic service, cross-layer resource allocation, QoE, B_CPSO, OWN

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1211 Ambient Notifications and the Interruption Effect

Authors: Trapond Hiransalee

Abstract:

The technology of mobile devices has changed our daily lives. Since smartphone have become a multi-functional device, many people spend unnecessary time on them, and could be interrupted by inappropriate notifications such as unimportant messages from social media. Notifications from smartphone could draw people’s attention and distract them from their priorities and current tasks. This research investigated that if the users were notified by their surroundings instead of smartphone, would it create less distraction and keep their focus on the present task. The experiment was a simulation of a lamp and door notification. Notifications related to work will be embedded in the lamp such as an email from a colleague. A notification that is useful when going outside such as weather information, traffic information, and schedule reminder will be embedded in the door. The experiment was conducted by sending notifications to the participant while he or she was working on a primary task and the working performance was measured. The results show that the lamp notification had fewer interruption effects than the smartphone. For the door notification, it was simulated in order to gain opinions and insights on ambient notifications from participants. Many participants agreed that the ambient notifications are useful and being informed by them could lessen the usage of their smartphone. The results and insights from this research could be used to guide the design process of ambient notifications.

Keywords: HCI, interaction, interaction design, usability testing

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1210 Technologies for Phosphorus Removal from Wastewater: Review

Authors: Thandie Veronicah Sima, Moatlhodi Wiseman Letshwenyo

Abstract:

Discharge of wastewater is one of the major sources of phosphorus entering streams, lakes and other water bodies causing undesired environmental problem such as eutrophication. This condition not only puts the ecosystem at risk but also causes severe economic damages. Stringent laws have been developed globally by different bodies to control the level of phosphorus concentrations into receiving environments. In order to satisfy the constraints, a high degree of tertiary treatment or at least a significant reduction of phosphorus concentration is obligatory. This comprehensive review summarizes phosphorus removal technologies, from the most commonly used conventional technologies such as chemical precipitation through metal addition, membrane filtration, reverse osmosis and enhanced biological phosphorus removal using activated sludge system to passive systems such as constructed wetlands and filtration systems. Trends, perspectives and scientific procedures conducted by different researchers have been presented. This review critically evaluates the advantages and limitations behind each of the technologies. Enhancement of passive systems using reactive media such as industrial wastes to provide additional uptake through adsorption or precipitation is also discussed in this article.

Keywords: adsorption, chemical precipitation, enhanced biological phosphorus removal, phosphorus removal

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1209 Developing a Set of Primers Targeting Chondroitin Ac Lyase Gene for Specific and Sensitive Detection of Flavobacterium Columnare, a Causative Agent of Freshwater Columnaris

Authors: Mahmoud Mabrok, Channarong Rodkhum

Abstract:

Flavobacterium columanre is one of the devastating pathogen that causes noticeable economic losses in freshwater cultured fish. Like other filamentous bacteria, F. columanre tends to aggregate and fluctuate to all kind of media, thus revealing obstacles in recognition of its colonies. Since the molecular typing is the only fundamental tool for rapid and precise detection of this pathgen. The present study developed a species-specific PCR assay based on cslA unique gene of F. columnare. The cslA gene sequences of 13 F. columnare, strains retrieved from gene bank database, were aligned to identify a conserved homologous segment prior to primers design. The new primers yielded amplicons of 287 bp from F. columnare strains but not from relevant or other pathogens, unlike to other published set that showed no specificity and cross-reactivity with F. indicum. The primers were sensitive and detected as few as 7 CFUs of bacteria and 3 pg of gDNA template. The sensitivity was reduced ten times when using tissue samples. These primers precisely defined all field isolates in a double-blind study, proposing their applicable use for field detection.

Keywords: Columnaris infection, cslA gene, Flavobacterium columnare, PCR

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1208 Evaluating Contextually Targeted Advertising with Attention Measurement

Authors: John Hawkins, Graham Burton

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Contextual targeting is a common strategy for advertising that places marketing messages in media locations that are expected to be aligned with the target audience. There are multiple major challenges to contextual targeting: the ideal categorisation scheme needs to be known, as well as the most appropriate subsections of that scheme for a given campaign or creative. In addition, the campaign reach is typically limited when targeting becomes narrow, so a balance must be struck between requirements. Finally, refinement of the process is limited by the use of evaluation methods that are either rapid but non-specific (click through rates), or reliable but slow and costly (conversions or brand recall studies). In this study we evaluate the use of attention measurement as a technique for understanding the performance of targeting on the basis of specific contextual topics. We perform the analysis using a large scale dataset of impressions categorised using the iAB V2.0 taxonomy. We evaluate multiple levels of the categorisation hierarchy, using categories at different positions within an initial creative specific ranking. The results illustrate that measuring attention time is an affective signal for the performance of a specific creative within a specific context. Performance is sustained across a ranking of categories from one period to another.

Keywords: contextual targeting, digital advertising, attention measurement, marketing performance

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1207 Solutions for Strengthening China-Japan-South Korea (CJK) Trilateral Cooperation: Focusing on the Management of Historical Conflicts

Authors: Yongmei Li, Chang-Gun Park

Abstract:

China-Japan-South Korea (CJK) trilateral cooperation has experienced historical challenges in recent years, which negatively influenced the development of their relationship. Results of the interviews with three citizens on trilateral relations illustrate that most people are concerned with the historical conflicts among CJK. This paper specifically focuses on managing historical issues, including comfort women issues, territorial disputes, and divergence in historical education. Accordingly, the effectiveness of management of tensions productively provides a method for detecting historical concerns, managing issues, and connecting the three countries and citizens through advocating for fair media reporting, effective network institutionalization, and active local government cooperation. Furthermore, this paper contributes to providing government solutions for reinforcing the CJK partnership. It specially involves history education, East Asian identity and mutual trust establishment, East Asia intra-regional exchange programs, and reorganization of the role of the Trilateral Cooperation Secretariat (TCS).

Keywords: China-Japan-South Korea, trilateral cooperation, government solutions, effectiveness of management, historical conflicts

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1206 Multi-Class Text Classification Using Ensembles of Classifiers

Authors: Syed Basit Ali Shah Bukhari, Yan Qiang, Saad Abdul Rauf, Syed Saqlaina Bukhari

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Text Classification is the methodology to classify any given text into the respective category from a given set of categories. It is highly important and vital to use proper set of pre-processing , feature selection and classification techniques to achieve this purpose. In this paper we have used different ensemble techniques along with variance in feature selection parameters to see the change in overall accuracy of the result and also on some other individual class based features which include precision value of each individual category of the text. After subjecting our data through pre-processing and feature selection techniques , different individual classifiers were tested first and after that classifiers were combined to form ensembles to increase their accuracy. Later we also studied the impact of decreasing the classification categories on over all accuracy of data. Text classification is highly used in sentiment analysis on social media sites such as twitter for realizing people’s opinions about any cause or it is also used to analyze customer’s reviews about certain products or services. Opinion mining is a vital task in data mining and text categorization is a back-bone to opinion mining.

Keywords: Natural Language Processing, Ensemble Classifier, Bagging Classifier, AdaBoost

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1205 Promoting Visual Literacy from Primary to Tertiary Levels through Literature

Authors: Mohd Nazri Latiff Azmi, Mairas Abd Rahman

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Traditionally, literacy has been commonly defined as the ability to read and write at an adequate level of proficiency that is necessary for communication. However, as time goes by, literacy has started to refer to reading and writing at a level adequate for communication, or at a level that lets one understand and communicate ideas in a literate society, so as to take part in that society. Meanwhile, visual literacy is a set of abilities that enables an individual to effectively find, interpret, evaluate, use, and create images and visual media. This study aims to investigate the collaboration between visual literacy and literature, eventually to determine how visual literacy can enhance learner’s ability to comprehend literary texts such as poems and short stories and develop his intellectuality, especially critical and creative thinking skills, and also to find out the different impacts of literature in visual literacy at four levels of education: pre-school, primary and secondary schools and university. This study is based on Malaysian environment and involves a qualitative method consisting of observation and interviews. The initial findings show that people with different levels of education grasp visual literacy differently but all levels show outstanding impacts of using literature.

Keywords: visual literacy, literature, language studies, higher education

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1204 Social Media Mining with R. Twitter Analyses

Authors: Diana Codat

Abstract:

Tweets' analysis is part of text mining. Each document is a written text. It's possible to apply the usual text search techniques, in particular by switching to the bag-of-words representation. But the tweets induce peculiarities. Some may enrich the analysis. Thus, their length is calibrated (at least as far as public messages are concerned), special characters make it possible to identify authors (@) and themes (#), the tweet and retweet mechanisms make it possible to follow the diffusion of the information. Conversely, other characteristics may disrupt the analyzes. Because space is limited, authors often use abbreviations, emoticons to express feelings, and they do not pay much attention to spelling. All this creates noise that can complicate the task. The tweets carry a lot of potentially interesting information. Their exploitation is one of the main axes of the analysis of the social networks. We show how to access Twitter-related messages. We will initiate a study of the properties of the tweets, and we will follow up on the exploitation of the content of the messages. We will work under R with the package 'twitteR'. The study of tweets is a strong focus of analysis of social networks because Twitter has become an important vector of communication. This example shows that it is easy to initiate an analysis from data extracted directly online. The data preparation phase is of great importance.

Keywords: data mining, language R, social networks, Twitter

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1203 A Fractional Derivative Model to Quantify Non-Darcy Flow in Porous and Fractured Media

Authors: Golden J. Zhang, Dongbao Zhou

Abstract:

Darcy’s law is the fundamental theory in fluid dynamics and engineering applications. Although Darcy linearity was found to be valid for slow, viscous flow, non-linear and non-Darcian flow has been well documented under both small and large velocity fluid flow. Various classical models were proposed and used widely to quantify non-Darcian flow, including the well-known Forchheimer, Izbash, and Swartzendruber models. Applications, however, revealed limitations of these models. Here we propose a general model built upon the Caputo fractional derivative to quantify non-Darcian flow for various flows (laminar to turbulence).Real-world applications and model comparisons showed that the new fractional-derivative model, which extends the fractional model proposed recently by Zhou and Yang (2018), can capture the non-Darcian flow in the relatively small velocity in low-permeability deposits and the relatively high velocity in high-permeability sand. A scale effect was also identified for non-Darcian flow in fractured rocks. Therefore, fractional calculus may provide an efficient tool to improve classical models to quantify fluid dynamics in aquatic environments.

Keywords: fractional derivative, darcy’s law, non-darcian flow, fluid dynamics

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1202 Titanium Dioxide Modified with Glutathione as Potential Drug Carrier with Reduced Toxic Properties

Authors: Olga Długosz, Jolanta Pulit-Prociak, Marcin Banach

Abstract:

The paper presents a process to obtain glutathione-modified titanium oxide nanoparticles. The processes were carried out in a microwave radiation field. The influence of the molar ratio of glutathione to titanium oxide and the effect of the fold of NaOH vs. stoichiometric amount on the size of the formed TiO₂ nanoparticles was determined. The physicochemical properties of the obtained products were evaluated using dynamic light scattering (DLS), transmission electron microscope- energy-dispersive X-ray spectroscopy (TEM-EDS), low-temperature nitrogen adsorption method (BET), X-Ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) microscopy methods. The size of TiO₂ nanoparticles was characterized from 30 to 336 nm. The release of titanium ions from the prepared products was evaluated. These studies were carried out using different media in which the powders were incubated for a specific time. These were water, SBF and Ringer's solution. The release of titanium ions from modified products is weaker compared to unmodified titanium oxide nanoparticles. The reduced release of titanium ions may allow the use of such modified materials as substances in drug delivery systems.

Keywords: titanium dioxide, nanoparticles, drug carrier, glutathione

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1201 Titanium Dioxide Modified with Glutathione as Potential Drug Carrier with Reduced Toxic Properties

Authors: Olga Długosz, Jolanta Pulit-Prociak, Marcin Banach

Abstract:

The paper presents a process to obtain glutathione-modified titanium oxide nanoparticles. The processes were carried out in a microwave radiation field. The influence of the molar ratio of glutathione to titanium oxide and the effect of the fold of NaOH vs. stoichiometric amount on the size of the formed TiO₂ nanoparticles was determined. The physicochemical properties of the obtained products were evaluated using dynamic light scattering (DLS), transmission electron microscope- energy-dispersive X-ray spectroscopy (TEM-EDS), low-temperature nitrogen adsorption method (BET), X-Ray Diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) microscopy methods. The size of TiO₂ nanoparticles was characterized from 30 to 336 nm. The release of titanium ions from the prepared products was evaluated. These studies were carried out using different media in which the powders were incubated for a specific time. These were: water, SBF, and Ringer's solution. The release of titanium ions from modified products is weaker compared to unmodified titanium oxide nanoparticles. The reduced release of titanium ions may allow the use of such modified materials as substances in drug delivery systems.

Keywords: titanium dioxide, nanoparticles, drug carrier, glutathione

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1200 Promoting Stem Education and a Cosmic Perspective by Using 21st Century Science of Learning

Authors: Rohan Roberts

Abstract:

The purpose of this project was to collaborate with a group of high-functioning, more-able students (aged 15-18) to promote STEM Education and a love for science by bringing a cosmic perspective into the classroom and high school environment. This was done using 21st century science of learning, a focus on the latest research on Neuroeducation, and modern pedagogical methods based on Howard Gardner's theory of Multiple Intelligences, Bill Lucas’ theory of New Smarts, and Sir Ken Robinson’s recommendations on encouraging creativity. The result was an increased sense of passion, excitement, and wonder about science in general, and about the marvels of space and the universe in particular. In addition to numerous unique and innovative science-based initiatives, clubs, workshops, and science trips, this project also saw a marked rise in student-teacher collaboration in science learning and in student engagement with the general public through the press, social media, and community-based initiatives. This paper also outlines the practical impact that bringing a cosmic perspective into the classroom has had on the lives, interests, and future career prospects of the students involved in this endeavour.

Keywords: cosmic perspective, gifted and talented, neuro-education, STEM education

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1199 Geovisualization of Human Mobility Patterns in Los Angeles Using Twitter Data

Authors: Linna Li

Abstract:

The capability to move around places is doubtless very important for individuals to maintain good health and social functions. People’s activities in space and time have long been a research topic in behavioral and socio-economic studies, particularly focusing on the highly dynamic urban environment. By analyzing groups of people who share similar activity patterns, many socio-economic and socio-demographic problems and their relationships with individual behavior preferences can be revealed. Los Angeles, known for its large population, ethnic diversity, cultural mixing, and entertainment industry, faces great transportation challenges such as traffic congestion, parking difficulties, and long commuting. Understanding people’s travel behavior and movement patterns in this metropolis sheds light on potential solutions to complex problems regarding urban mobility. This project visualizes people’s trajectories in Greater Los Angeles (L.A.) Area over a period of two months using Twitter data. A Python script was used to collect georeferenced tweets within the Greater L.A. Area including Ventura, San Bernardino, Riverside, Los Angeles, and Orange counties. Information associated with tweets includes text, time, location, and user ID. Information associated with users includes name, the number of followers, etc. Both aggregated and individual activity patterns are demonstrated using various geovisualization techniques. Locations of individual Twitter users were aggregated to create a surface of activity hot spots at different time instants using kernel density estimation, which shows the dynamic flow of people’s movement throughout the metropolis in a twenty-four-hour cycle. In the 3D geovisualization interface, the z-axis indicates time that covers 24 hours, and the x-y plane shows the geographic space of the city. Any two points on the z axis can be selected for displaying activity density surface within a particular time period. In addition, daily trajectories of Twitter users were created using space-time paths that show the continuous movement of individuals throughout the day. When a personal trajectory is overlaid on top of ancillary layers including land use and road networks in 3D visualization, the vivid representation of a realistic view of the urban environment boosts situational awareness of the map reader. A comparison of the same individual’s paths on different days shows some regular patterns on weekdays for some Twitter users, but for some other users, their daily trajectories are more irregular and sporadic. This research makes contributions in two major areas: geovisualization of spatial footprints to understand travel behavior using the big data approach and dynamic representation of activity space in the Greater Los Angeles Area. Unlike traditional travel surveys, social media (e.g., Twitter) provides an inexpensive way of data collection on spatio-temporal footprints. The visualization techniques used in this project are also valuable for analyzing other spatio-temporal data in the exploratory stage, thus leading to informed decisions about generating and testing hypotheses for further investigation. The next step of this research is to separate users into different groups based on gender/ethnic origin and compare their daily trajectory patterns.

Keywords: geovisualization, human mobility pattern, Los Angeles, social media

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1198 Hate Speech Detection Using Machine Learning: A Survey

Authors: Edemealem Desalegn Kingawa, Kafte Tasew Timkete, Mekashaw Girmaw Abebe, Terefe Feyisa, Abiyot Bitew Mihretie, Senait Teklemarkos Haile

Abstract:

Currently, hate speech is a growing challenge for society, individuals, policymakers, and researchers, as social media platforms make it easy to anonymously create and grow online friends and followers and provide an online forum for debate about specific issues of community life, culture, politics, and others. Despite this, research on identifying and detecting hate speech is not satisfactory performance, and this is why future research on this issue is constantly called for. This paper provides a systematic review of the literature in this field, with a focus on approaches like word embedding techniques, machine learning, deep learning technologies, hate speech terminology, and other state-of-the-art technologies with challenges. In this paper, we have made a systematic review of the last six years of literature from Research Gate and Google Scholar. Furthermore, limitations, along with algorithm selection and use challenges, data collection, and cleaning challenges, and future research directions, are discussed in detail.

Keywords: Amharic hate speech, deep learning approach, hate speech detection review, Afaan Oromo hate speech detection

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1197 Tensile and Fracture Properties of Cast and Forged Composite Synthesized by Addition of in-situ Generated Al3Ti-Al2O3 Particles to Magnesium

Authors: H. M. Nanjundaswamy, S. K. Nath, S. Ray

Abstract:

TiO2 particles have been added in molten aluminium to result in aluminium based cast Al/Al3Ti-Al2O3 composite, which has been added then to molten magnesium to synthesize magnesium based cast Mg-Al/Al3Ti-Al2O3 composite. The nominal compositions in terms of Mg, Al, and TiO2 contents in the magnesium based composites are Mg-9Al-0.6TiO2, Mg-9Al-0.8TiO2, Mg-9Al-1.0TiO2 and Mg-9Al-1.2TiO2 designated respectively as MA6T, MA8T, MA10T and MA12T. The microstructure of the cast magnesium based composite shows grayish rods of intermetallics Al3Ti, inherited from aluminium based composite but these rods, on hot forging, breaks into smaller lengths decreasing the average aspect ratio (length to diameter) from 7.5 to 3.0. There are also cavities in between the broken segments of rods. β-phase in cast microstructure, Mg17Al12, dissolves during heating prior to forging and re-precipitates as relatively finer particles on cooling. The amount of β-phase also decreases on forging as segregation is removed. In both the cast and forged composite, the Brinell hardness increases rapidly with increasing addition of TiO2 but the hardness is higher in forged composites by about 80 BHN. With addition of higher level of TiO2 in magnesium based cast composite, yield strength decreases progressively but there is marginal increase in yield strength over that of the cast Mg-9 wt. pct. Al, designated as MA alloy. But the ultimate tensile strength (UTS) in the cast composites decreases with the increasing particle content indicating possibly an early initiation of crack in the brittle inter-dendritic region and their easy propagation through the interfaces of the particles. In forged composites, there is a significant improvement in both yield strength and UTS with increasing TiO2 addition and also, over those observed in their cast counterpart, but at higher addition it decreases. It may also be noted that as in forged MA alloy, incomplete recovery of forging strain increases the strength of the matrix in the composites and the ductility decreases both in the forged alloy and the composites. Initiation fracture toughness, JIC, decreases drastically in cast composites compared to that in MA alloy due to the presence of intermetallic Al3Ti and Al2O3 particles in the composite. There is drastic reduction of JIC on forging both in the alloy and the composites, possibly due to incomplete recovery of forging strain in both as well as breaking of Al3Ti rods and the voids between the broken segments of Al3Ti rods in composites. The ratio of tearing modulus to elastic modulus in cast composites show higher ratio, which increases with the increasing TiO2 addition. The ratio decreases comparatively more on forging of cast MA alloy than those in forged composites.

Keywords: composite, fracture toughness, forging, tensile properties

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1196 South Asia’s Political Landscape: Precipitating Terrorism

Authors: Saroj Kumar Rath

Abstract:

India's Muslims represent 15 percent of the nation's population, the world's third largest group in any nation after Indonesia and Pakistan. Extremist groups like the Islamic State, Al Qaeda, the Taliban and the Haqqani network increasingly view India as a target. Several trends explain the rise: Terrorism threats in South Asia are linked and mobile - if one source is batted down, jihadists relocate to find another Islamic cause. As NATO withdraws from Afghanistan, some jihadists will eye India. Pakistan regards India as a top enemy and some officials even encourage terrorists to target areas like Kashmir or Mumbai. Meanwhile, a stream of Wahhabi preachers have visited India, offering hard-line messages; extremist groups like Al Qaeda and the Islamic State compete for influence, and militants even pay jihadists. Muslims as a minority population in India could offer fertile ground for the extremist recruiters. This paper argues that there is an urgent need for the Indian government to profile militants and examine social media sites to attack Wahhabi indoctrination while supporting education and entrepreneurship for all of India's citizens.

Keywords: Al Qaeda, terrorism, Islamic state, India, haqqani network, Pakistan, Taliban

Procedia PDF Downloads 598
1195 Modeling of the Flow through an Earth Dam and Geotechnical Slope Analyzes

Authors: Ahmed Ferhati, Arezki Adjrad, Ratiba Mitiche-Kettab, Hakim Djafer Khodja

Abstract:

The porous media are omnipresent around us that they are natural as sand, clay, rocks, or manufactured like concretes, cement, and ceramics. The variety of porous environment indicates a wide material range which can be very different from each other. Their common point is to be made up of a solid matrix and a porous space. In our case of study, we made the modeling of the flows in porous environments through the massives as in the case of an earth dam. The computer code used (PLAXIS) offer the possibility of modeling of various structures, in particular, the works in lands because that it deals with the pore water pressure due to the underground flow and the calculation of the plastic deformations. To confirm results obtained by PLAXIS, GeoStudio SEEP/W code was used. This work treats modeling of flows and mechanical and hydraulic behavior of earth dam. A general framework which can fit the calculation of this kind of structures and the coupling of the soil consolidation and free surface flows was defined. In this study; we have confronted a real case modeling of an earth dam. It was shown, in particular, that it is possible to entirely lead the calculation of real dam and to get encouraging results from the hydraulic and mechanical point of view.

Keywords: analyzes, dam, flow, modeling, PLAXIS, seep/w, slope

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1194 Newspaper Reportage and Framing of President Muhammadu Buhari’s Anti-Corruption Campaign in Nigeria

Authors: Diane Ezeh-Aruah

Abstract:

This study examined newspaper coverage of President Muhammadu Buhar’s anti-corruption crusade, a case study of Guardian, Nation, Sun and Vanguard newspapers. It assessed the frequency of coverage given to President Buhari’s war against corruption, the prominence of coverage, the angles/framing of topics and the direction of the news stories. The determinants of the prominence of coverage were page placement, length of the story, illustrations and story types. The author made use of agenda setting and framing theories. The research was carried through the method of survey, by distribution of copies of the questionnaire. The result of this study showed that the media gave adequate coverage of President Buhari’s anti-corruption war, even though the reports were not many in the early stages of the law enactment, but the coverages lacked prominence as most of the major stories were not given front page coverage; they lacked pictorial illustrations and not exhaustive enough to be impactful. Newspaper organizations are therefore encouraged to include humanistic angles in their corruption stories rather than focus highly on political angles. They should adopt the elements of investigative and interpretative journalism in their coverage of corruption news.

Keywords: newspaper, coverage, president Muhammadu Buhari, anti-corruption campaign

Procedia PDF Downloads 161