Search results for: high tech

Authors: Teng Li, Kamran Mohseni

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This paper presents an inviscid regularization technique for the incompressible two-phase flow simulations. This technique is known as observable method due to the understanding of observability that any feature smaller than the actual resolution (physical or numerical), i.e., the size of wire in hotwire anemometry or the grid size in numerical simulations, is not able to be captured or observed. Differ from most regularization techniques that applies on the numerical discretization, the observable method is employed at PDE level during the derivation of equations. Difficulties in the simulation and analysis of realistic fluid flow often result from discontinuities (or near-discontinuities) in the calculated fluid properties or state. Accurately capturing these discontinuities is especially crucial when simulating flows involving shocks, turbulence or sharp interfaces. Over the past several years, the properties of this new regularization technique have been investigated that show the capability of simultaneously regularizing shocks and turbulence. The observable method has been performed on the direct numerical simulations of shocks and turbulence where the discontinuities are successfully regularized and flow features are well captured. In the current paper, the observable method will be extended to two-phase interfacial flows. Multiphase flows share the similar features with shocks and turbulence that is the nonlinear irregularity caused by the nonlinear terms in the governing equations, namely, Euler equations. In the direct numerical simulation of two-phase flows, the interfaces are usually treated as the smooth transition of the properties from one fluid phase to the other. However, in high Reynolds number or low viscosity flows, the nonlinear terms will generate smaller scales which will sharpen the interface, causing discontinuities. Many numerical methods for two-phase flows fail at high Reynolds number case while some others depend on the numerical diffusion from spatial discretization. The observable method regularizes this nonlinear mechanism by filtering the convective terms and this process is inviscid. The filtering effect is controlled by an observable scale which is usually about a grid length. Single rising bubble and Rayleigh-Taylor instability are studied, in particular, to examine the performance of the observable method. A pseudo-spectral method is used for spatial discretization which will not introduce numerical diffusion, and a Total Variation Diminishing (TVD) Runge Kutta method is applied for time integration. The observable incompressible Euler equations are solved for these two problems. In rising bubble problem, the terminal velocity and shape of the bubble are particularly examined and compared with experiments and other numerical results. In the Rayleigh-Taylor instability, the shape of the interface are studied for different observable scale and the spike and bubble velocities, as well as positions (under a proper observable scale), are compared with other simulation results. The results indicate that this regularization technique can potentially regularize the sharp interface in the two-phase flow simulations

Keywords: Euler equations, incompressible flow simulation, inviscid regularization technique, two-phase flow

Procedia PDF Downloads 483

Authors: Boy Arief Fachri

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Even its content is rich in antioxidants ϒ-oryzanol, rice bran is not used properly as functional food. This research aims to (1) extract ϒ-oryzanol; (2) determine the solubility of ϒ-oryzanol in supercritical CO₂ based on phase equilibrium theory; and (3) study the effect of process variables on solubility. Extraction experiments were carried out for rice bran (5 g) at various extraction pressures, temperatures and reaction times. The flowrate of supercritical fluid through the extraction vessel was 25 g/min. The extracts were collected and analysed with high-pressure liquid chromatography (HPLC). The conclusion based on the experiments are as: (1) The highest experimental solubility was 0.303 mcg/mL RBO at T= 60°C, P= 90 atm, t= 30 min; (2) Solubility of ϒ-oryzanol was influenced by pressure and temperature. As the pressure and temperature increase, the solubility increases; (3) The solubility data of supercritical extraction can be successfully determined using phase equilibrium theory. Meanwhile, tocopherol was found and slightly investigated in this work.

Keywords: rice bran, solubility, supercritical CO2, ϒ-orizanol

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Authors: Ji-Sun Lee, Soong-Keun Hyun, Jin-Ho Kim

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In this study, a glass fiber is fabricated using a continuous spinning process from alkali resistant (AR) glass with 4 wt% zirconia. In order to confirm the melting properties of the marble glass, the raw material is placed into a Pt crucible and melted at 1650 ℃ for 2 h, and then annealed. In order to confirm the transparency of the clear marble glass, the visible transmittance is measured, and the fiber spinning condition is investigated by using high temperature viscosity measurements. A change in the diameter is observed according to the winding speed in the range of 100–900 rpm; it is also verified as a function of the fiberizing temperature in the range of 1200–1260 ℃. The optimum winding speed and spinning temperature are 500 rpm and 1240 ℃, respectively. The properties of the prepared spinning fiber are confirmed using optical microscope, tensile strength, modulus, and alkali-resistant tests.

Keywords: glass composition, fiber diameter, continuous filament fiber, continuous spinning, physical properties

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Authors: Adeep Hande, Shubham Agarwal

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This paper presents a study on identifying sexism in online texts using various state-of-the-art deep learning models based on BERT. We experimented with different feature sets and model architectures and evaluated their performance using precision, recall, F1 score, and accuracy metrics. We also explored the use of pseudolabeling technique to improve model performance. Our experiments show that the best-performing models were based on BERT, and their multilingual model achieved an F1 score of 0.83. Furthermore, the use of pseudolabeling significantly improved the performance of the BERT-based models, with the best results achieved using the pseudolabeling technique. Our findings suggest that BERT-based models with pseudolabeling hold great promise for identifying sexism in online texts with high accuracy.

Keywords: large language models, semi-supervised learning, sexism detection, data sparsity

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Authors: Bahram Soltani, Louai Ghazieh

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Following the high profile financial scandals of 2007-2008, corporate management has been faced with strong pressures resulting from more regulatory requirements, as well as the increasing expectations of various groups of stakeholders. The responsibility acquired a big importance in front of this financial crisis. This responsibility requires more transparency and communication, inside the company with the collaborators and outside of the company with the society, while companies try to improve the degree of control and to authorize managers to realize the objectives of the company. The objective of this paper is to present the concept of the responsibility generally and the various types of manager’s responsibility in private individual within the company, as well as the explanatory theories of this responsibility through the various perspectives such as: economic, political, social and behavioral. This study should have academic and practical contributions particularly for regulators seeking to improve the companies’ practices and organizational functioning within capital market economy.

Keywords: manager, accountability, corporate performance, financial crisis, behavior

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Authors: James D. Beauchemin

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This study tested whether youth mental health care quality, operationalized as the extent to which youth and families experienced system-of-care principles in service interactions with providers, varied by level of youth need after adjusting for sociodemographic and treatment factors. The relationship of quality to clinical outcomes was also examined. Using administrative data and cross-sectional surveys from a stratified random sample of 1,124 caregivers of youths ages 5 to 20 within a statewide system-of-care, adjusted analyses indicated youths with the most intensive needs were significantly less likely to experience high-quality care (51% vs. 63%, p=0.016), with marked deficits on 6 of 9 items. Receipt of lower-quality care predicted less improvement in youth functioning. Despite considerable effort to develop systems-of-care for youths with the most severe mental health needs, these data suggest quality disparities remain for the most impaired youths. Policy and intervention development may be needed to improve the quality of care for this population.

Keywords: system-of-care, adherence, mental health, youth

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Authors: Mansour Fakhri, Monire Zokaei

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Where there are many demolitions on conventional asphalt pavements, heavy costs are paid to repair and reconstruct the pavement roads annually. Recently some research has been done in order to increase the pavement life. Perpetual pavement is regarded as one of them which can improve the pavement life and minimize the maintenance activity and cost. In this research, ABAQUS which is a finite element software is implemented for analyzing and simulation of perpetual pavement. Viscoelastic model of material is used and loading wheel is considered to be dynamic. Effect of different parameters on pavement function has been considered. Because of high primary cost these pavements are not widely used. In this regard, life cost analysis was also carried out to compare perpetual pavement to conventional asphalt concrete pavement. It was concluded that although the initial cost of perpetual pavement is higher than that of conventional asphalt pavement, life cycle cost analysis during 50 years of service life showed that the performance of this pavement is better and the whole life cost of that is less.

Keywords: ABAQUS, lifecycle cost analysis, mechanistic empirical, perpetual pavement

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Authors: Edwina G. Rodrigues, S. J. Bindhu, A. V. Rajesh

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This paper proposes a switched capacitor based driver circuit for high power light emitting diodes with a front end rectifier. LEDs are low-voltage light sources, requiring a constant DC voltage or current to operate optimally. LEDs, therefore, require a device that can convert incoming AC power to the proper DC voltage, and regulate the current flowing through the LED during operation. Proposed topology has a front end converter. It is an AC-DC rectifier that works on bridgeless boost topology which shapes the input current waveform. The front end converter is followed by a DC-DC converter which provides a constant DC voltage across the LEDs. A 12V AC input is given to the input of frontend converter which rectifies and boost the voltage to 24v DC and gives it to the DC-DC converter. The DC-DC converter converts the 24V DC and regulates this constant DC voltage across the LEDs.

Keywords: bridgeless rectifier, power factor correction(PFC), SC converter, total harmonic distortion (THD)

Procedia PDF Downloads 859

Authors: Wei-Hao Lee, Ta-Wui Cheng, Yung-Chin Ding, Tai-Tien Wang

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The purpose of this study is trying to use marble wastes as the raw material to fabricate geopolymer green mortar / concrete. Experiment results show that using marble to make geopolymer mortar and concrete, the compressive strength after 28 days curing can reach 35 MPa and 25 MPa, respectively. The characteristics of marble-based geopolymer green mortar and concrete will keep testing for a long term in order to understand the effect parameters. The study is based on resource recovery and recycling. Its basic characteristics are low consumption, low carbon dioxide emission and high efficiency that meet the international tendency 'Circular Economy.' By comparing with Portland cement mortar and concrete, production 1 ton of marble-based geopolymer mortar and concrete, they can be saved around 50.3% and 49.6% carbon dioxide emission, respectively. Production 1 m3 of marble-based geopolymer concrete costs about 62 USD that cheaper than that of traditional Portland concrete. It is proved that the marble-based geopolymer concrete has great potential for further engineering development.

Keywords: marble, geopolymer, geopolymer concrete, CO₂ emission

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Authors: Ujjal Chattaraj, Pbharat Saikumar, Thinley Dorji

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Earth is going to be a planet where no further life can sustain if people continue to pollute the environment. We need energy and fuels everyday for heating and lighting purposes in our life. It’s high time we know this problem and take measures at-least to reduce pollution and take alternative measures for everyday livelihood. Biogas is one of them. It is very essential to define and control the parameters for optimization of biogas production. Biogas plants can be made of different size, but it is very vital to make a biogas which will be cost effective, with greater efficiency (more production) and biogas plants that will sustain for a longer period of time for usage. In this research, experiments were carried out only on cow dung and Chicken manure depending on the substrates people out there (Bhutan) used. The experiment was done within 25 days and was tested for different temperatures and found out which produce more amount. Moreover, it was also statistically tested for their dependency and non-dependency which gave clear idea more on their production.

Keywords: digester, mesophilic temperature, organic manure, statistical analysis, thermophilic temperature, t-test

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Authors: Brian Yulianto, Syachrial, Saeful Aziz, Anggita Clara Shinta

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Indonesia, with a population of about two hundred and fifty million people in quantity, indicates the outstanding wealth of human resources. Hundreds of millions of the population scattered in various communities in various regions in Indonesia with the different characteristics of economic, social and unique culture. Broadly speaking, the community in Indonesia is divided into two classes, namely urban communities and rural communities. The rural communities characterized by low potential and management of natural and human resources, limited access of development, and lack of social and economic infrastructure, and scattered and isolated population. West Java is one of the provinces with the largest population in Indonesia. Based on data from the Central Bureau of Statistics in 2015 the number of population in West Java reached 46.7096 million souls spread over 18 districts and 9 cities. The big difference in geographical and social conditions of people in West Java from one region to another, especially the south to the north causing the gap is high. It is closely related to the flow of investment to promote the area. Poverty and underdevelopment are the classic problems that occur on a massive scale in the region as the effects of inequity in development. South Cianjur and Tasikmalaya area South became one of the portraits area where the existing potential has not been capable of prospering society. Tri Dharma College not only define the College as a pioneer implementation of education and research to improve the quality of human resources but also demanded to be a pioneer in the development through the concept of public service. Bandung Institute of Technology as one of the institutions of higher education to implement community service system through collaborative community work program "one of the university community" as one approach to developing villages. The program is based Community Service, where students are not only required to be able to take part in community service, but also able to develop a community development strategy that is comprehensive and integrity in cooperation with government agencies and non-government related as a real form of effort alignment potential, position and role from various parties. Areas of western Java in particular have high poverty rates and disparity. On the other hand, there are three fundamental pillars in the development of rural communities, namely economic development, community development, and the integrated infrastructure development. These pillars require the commitment of all components of community, including the students and colleges for upholding success. College’s community program is one of the approaches in the development of rural communities. ITB is committed to implement as one form of student community service as community-college programs that integrate all elements of the community which is called Kuliah Kerja Nyata-Thematic.

Keywords: development in rural area, collaborative, student community service, Kuliah Kerja Nyata-Thematic ITB

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Authors: Quentin C.P. Bourgogne, Vanessa Bouchart, Pierre Chevrier, Emmanuel Dattoli

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This study presents an experimental and theoretical work conducted on a PolyPhenylene Sulfide reinforced with 40%wt of short glass fibers (PPS GF40) and its matrix. Thermoplastics are widely used in the automotive industry to lightweight automotive parts. The replacement of metallic parts by thermoplastics is reaching under-the-hood parts, near the engine. In this area, the parts are subjected to high temperatures and are immersed in cooling liquid. This liquid is composed of water and glycol and can affect the mechanical properties of the composite. The aim of this work was thus to quantify the evolution of mechanical properties of the thermoplastic composite, as a function of temperature and liquid aging effects, in order to develop a reliable design of parts. An experimental campaign in the tensile mode was carried out at different temperatures and for various glycol proportions in the cooling liquid, for monotonic and cyclic loadings on a neat and a reinforced PPS. The results of these tests allowed to highlight some of the main physical phenomena occurring during these solicitations under tough hydro-thermal conditions. Indeed, the performed tests showed that temperature and liquid cooling aging can affect the mechanical behavior of the material in several ways. The more the cooling liquid contains water, the more the mechanical behavior is affected. It was observed that PPS showed a higher sensitivity to absorption than to chemical aggressiveness of the cooling liquid, explaining this dominant sensitivity. Two kinds of behaviors were noted: an elasto-plastic type under the glass transition temperature and a visco-pseudo-plastic one above it. It was also shown that viscosity is the leading phenomenon above the glass transition temperature for the PPS and could also be important under this temperature, mostly under cyclic conditions and when the stress rate is low. Finally, it was observed that soliciting this composite at high temperatures is decreasing the advantages of the presence of fibers. A new phenomenological model was then built to take into account these experimental observations. This new model allowed the prediction of the evolution of mechanical properties as a function of the loading environment, with a reduced number of parameters compared to precedent studies. It was also shown that the presented approach enables the description and the prediction of the mechanical response with very good accuracy (2% of average error at worst), over a wide range of hydrothermal conditions. A temperature-humidity equivalence principle was underlined for the PPS, allowing the consideration of aging effects within the proposed model. Then, a limit of improvement of the reachable accuracy was determinate for all models using this set of data by the application of an artificial intelligence-based model allowing a comparison between artificial intelligence-based models and phenomenological based ones.

Keywords: aging, analytical modeling, mechanical testing, polymer matrix composites, sequential model, thermomechanical

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Authors: Pamphile Ndagijimana, Xuejiao Liu, Zhiwei Li, Yin Wang

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Enhancing the properties of activated carbon is very imperative for various applications. Indeed, the activated carbon has promising physicochemical properties desired for a considerable number of applications. In this regard, we are proposing an enhanced and green technology for increasing the efficiency and performance of the activated carbon to various applications. The technique poses on the use of natural extracts from tuberous and cereals based-solutions. These solutions showed high potentiality to be used in the synthesis of activated carbon-graphene composite with only 3 mL. The extracted liquid from tuberous sourcing was enough to induce precipitation within a fraction of a minute in contrast to that from cereal sourced. Using these extracts, a synthesis of activated carbon-graphene composite was successful. Different characterization techniques such as XRD, SEM, FTIR, BET, and Raman spectroscopy were performed to investigate the composite materials. The results confirmed a conjugation between activated carbon and graphene material.

Keywords: activated carbon, cereals, extract solution, graphene, tuberous

Procedia PDF Downloads 132

Authors: Angelis P. Barlampas

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Learning Objectives: The purpose of this study is to inform briefly the reader about the applications of AI in chest radiology. Background: Currently, there are 190 FDA-approved radiology AI applications, with 42 (22%) pertaining specifically to thoracic radiology. Imaging findings OR Procedure details Aids of AI in chest radiology1: Detects and segments pulmonary nodules. Subtracts bone to provide an unobstructed view of the underlying lung parenchyma and provides further information on nodule characteristics, such as nodule location, nodule two-dimensional size or three dimensional (3D) volume, change in nodule size over time, attenuation data (i.e., mean, minimum, and/or maximum Hounsfield units [HU]), morphological assessments, or combinations of the above. Reclassifies indeterminate pulmonary nodules into low or high risk with higher accuracy than conventional risk models. Detects pleural effusion . Differentiates tension pneumothorax from nontension pneumothorax. Detects cardiomegaly, calcification, consolidation, mediastinal widening, atelectasis, fibrosis and pneumoperitoneum. Localises automatically vertebrae segments, labels ribs and detects rib fractures. Measures the distance from the tube tip to the carina and localizes both endotracheal tubes and central vascular lines. Detects consolidation and progression of parenchymal diseases such as pulmonary fibrosis or chronic obstructive pulmonary disease (COPD).Can evaluate lobar volumes. Identifies and labels pulmonary bronchi and vasculature and quantifies air-trapping. Offers emphysema evaluation. Provides functional respiratory imaging, whereby high-resolution CT images are post-processed to quantify airflow by lung region and may be used to quantify key biomarkers such as airway resistance, air-trapping, ventilation mapping, lung and lobar volume, and blood vessel and airway volume. Assesses the lung parenchyma by way of density evaluation. Provides percentages of tissues within defined attenuation (HU) ranges besides furnishing automated lung segmentation and lung volume information. Improves image quality for noisy images with built-in denoising function. Detects emphysema, a common condition seen in patients with history of smoking and hyperdense or opacified regions, thereby aiding in the diagnosis of certain pathologies, such as COVID-19 pneumonia. It aids in cardiac segmentation and calcium detection, aorta segmentation and diameter measurements, and vertebral body segmentation and density measurements. Conclusion: The future is yet to come, but AI already is a helpful tool for the daily practice in radiology. It is assumed, that the continuing progression of the computerized systems and the improvements in software algorithms , will redder AI into the second hand of the radiologist.

Keywords: artificial intelligence, chest imaging, nodule detection, automated diagnoses

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Authors: Radia Guerza

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Tutoring at the Algerian University has been an issue of great controversy and debate. Henceforth, the current paper is an attempt to shed light on the issue of tutoring at Algerian University. It aims to set a plan for tutoring that might meet the student's needs and challenges. It endeavors to explore the following query: “what is the role of tutoring in the Algerian university between “The CAN DO” and “The HAVE TO”? To equate with the addressed research question, an exploratory small-scale study has been carried out at Batna 2 University using questionnaires and interviews with fifty (50) teachers. Results indicate that Algerian University is still lagging behind because of the huge lack of infrastructure means, human resources, and even pedagogical resources. In addition, the majority of our teachers are reluctant to adhere to the tutorial policy due to the lack of incentives; next to that, the increasing yearly number of students and students high ratio would hardly permit any tutoring sessions. Finally, this paper is the first attempt, to our best knowledge, towards raising the awareness of our institution, staff members, teachers, and students towards the importance of tutoring and how to adopt it.

Keywords: attitudes, higher education, perceptions, tutoring

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Authors: Osamah A. Alsayegh

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This paper contributes to the literature by updating the analysis of the impact of the recent oil prices fall on the renewable energy (RE) industry and deployment. The research analysis uses the Renewable Energy Industrial Index (RENIXX), which tracks the world’s 30 largest publicly traded companies and oil prices daily data from January 2003 to March 2016. RENIXX represents RE industries developing solar, wind, geothermal, bioenergy, hydropower and fuel cells technologies. This paper tests the hypothesis that claims high oil prices encourage the substitution of alternate energy sources for conventional energy sources. Furthermore, it discusses RENIXX performance behavior with respect to the governments’ policies factor that investors should take into account. Moreover, the paper proposes a theoretical model that relates RE industry progress with oil prices and policies through the fuzzy logic system.

Keywords: Fuzzy logic, investment, policy, stock exchange index

Procedia PDF Downloads 222

Authors: Lin Ji

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The 1923 HSBC Building is one of the landmarks of Shanghai's Bund complex and is described as "one of the finest buildings from the Suez Canal to the Bering Strait". Mr George Leopold Wilson of Palmer&Turner and his design team combine the latest British design taste with Chinese elements and bring the high standard of London manufacturing to Shanghai. This paper reviews the establishment background and construction process of the Hongkong and Shanghai Bank Corporation in Shanghai, and analyzes the characteristics of various styles and ornament of HSBC. At the same time, using the research method of iconography, compared with Britain's exploration of modern design mode in the early 20th century, we can deeply understand how this "monument of world commerce and prosperity" realizes the identity construction of its financial empire in the Far East in the perfect combination of practicality and artistry.

Keywords: early 20-century Shanghai, the bund, the HSBC building, classical styles, ornament, identity construction

Procedia PDF Downloads 127

Authors: Aliyah Dosani, Kerri Alderson

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Two different simulations using standardized patients were developed to reinforce content and foster undergraduate nursing students’ practice and development of interpersonal skills in difficult clinical situations in the classroom. The live actor simulations focused on fostering interpersonal skills, traditionally considered by students to be simple and easy. However, seemingly straightforward interactions can be very stressful, particularly in women’s complex social/emotional situations. Supporting patients in these contexts is fraught with complexity and high emotion, requiring skillful support, assessment and intervention by a registered nurse. In this presentation, the personal and professional perspectives of the development, incorporation, and execution of the live actor simulations will be discussed, as well as the inclusion of student perceptions, and the learning gained by the involved faculty.

Keywords: adult learning, interpersonal skill development, simulation learning, teaching and learning

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Authors: P. Dubcek, B. Pivac, J. Dasovic, V. Janicki, S. Bernstorff

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When grown only to nanometric sizes, metallic particles (e.g. Ag, Au and Cu) exhibit specific optical properties caused by the presence of plasmon band. The plasmon band represents collective oscillation of the conduction electrons, and causes a narrow band absorption of light in the visible range. When the nanoparticles are embedded in a dielectric, they also cause modifications of dielectrics optical properties. This can be fine-tuned by tuning the particle size. We investigated Cu nanoparticle growth with and without surrounding dielectric (SiO2 capping layer). The morphology and crystallinity were investigated by GISAXS and GIWAXS, respectively. Samples were produced by high vacuum thermal evaporation of Cu onto monocrystalline silicon substrate held at room temperature, 100°C or 180°C. One series was in situ capped by 10nm SiO2 layer. Additionally, samples were annealed at different temperatures up to 550°C, also in high vacuum. The room temperature deposited samples annealed at lower temperatures exhibit continuous film structure: strong oscillations in the GISAXS intensity are present especially in the capped samples. At higher temperatures enhanced surface dewetting and Cu nanoparticles (nanoislands) formation partially destroy the flatness of the interface. Therefore the particle type of scattering is enhanced, while the film fringes are depleted. However, capping layer hinders particle formation, and continuous film structure is preserved up to higher annealing temperatures (visible as strong and persistent fringes in GISAXS), compared to the non- capped samples. According to GISAXS, lateral particle sizes are reduced at higher temperatures, while particle height is increasing. This is ascribed to close packing of the formed particles at lower temperatures, and GISAXS deduced sizes are partially the result of the particle agglomerate dimensions. Lateral maxima in GISAXS are an indication of good positional correlation, and the particle to particle distance is increased as the particles grow with temperature elevation. This coordination is much stronger in the capped and lower temperature deposited samples. The dewetting is much more vigorous in the non-capped sample, and since nanoparticles are formed in a range of sizes, correlation is receding both with deposition and annealing temperature. Surface topology was checked by atomic force microscopy (AFM). Capped sample's surfaces were smoother and lateral size of the surface features were larger compared to the non-capped samples. Altogether, AFM results suggest somewhat larger particles and wider size distribution, and this can be attributed to the difference in probe size. Finally, the plasmonic effect was monitored by UV-Vis reflectance spectroscopy, and relative weak plasmonic effect could be explained by uncomplete dewetting or partial interconnection of the formed particles.

Keywords: coper, GISAXS, nanoparticles, plasmonics

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Authors: Monica Lia

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This paper has set the objective of researching how education is influenced by the information society. The first step was to define more precisely the information space. Second step was to identify how information space intersects the family space and institutional space educational levels represented by pre-school / school and pre-university (kindergarten, at elementary / middle school / high school). Interrelationship between the above-mentioned areas was another objective of the research. All these elements have been investigated through the original intention to identify how the information space can become an educational tool to support for the family space, education and institutional space. In addition, the aim of this research is to offer some solutions in this regard. Often the educational efforts appear to be blocked by the existence of this space. However, this paper demonstrates that Informational space can be an enemy of the educational system or be support systems if we know the internal structure and mechanisms. We can make the Informational Space to work for accomplish the educational objectives.

Keywords: informational space, education, educational tool, social diagram, information, information structure, lessons

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Authors: Ibrahim Alshunaibir

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Infection with Helicobacter pylori is common worldwide but few studies focus on the prevalence and spread of the infection in Saudi Arabia. This study was undertaken to observe the epidemiology of Helicobacter pylori infection in patients suffering from gastrointestinal sign and symptoms in one of the largest hospitals in the capital of Saudi Arabia, Riyadh. Methods: Enzyme-linked immunosorbent assay (ELISA) was undertaken for this study with nearly 6000 samples collected and examined for patients suffering from (dyspeptic) symptoms ranging in their age from 5 to 75 years. Results: The prevalence of helicobacter infection was 67% increasing with age. Female shows higher percentage of H. pylori infection than male. Conclusions: The percentage rate was higher in female than male. This study shows a high percentage of helicobacter infection in Saudi Arabia.

Keywords: Helicobacter pylori, percentage, dyspeptic, Saudi Arabia

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Authors: Evgeny N. Zakharin, Bartosz Majewski

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Foaming polyurethane is a ground improvement technology that is increasingly used for foundation stabilization with differential settlement and controlled foundation structure lifting. This technology differs from conventional mineral grout due to its injection composition, which provides high-pressure expansion quickly due to a chemical reaction. The technology has proven efficient in the typical geological conditions of the United Arab Emirates. An in-situ trial foundation load test has been proposed to objectively assess the deformative and load-bearing characteristics of the soil after injection. The article provides a detailed description of the experiment carried out in field conditions. Based on the practical experiment's results and its finite element modeling, the deformation modulus of the soil after treatment was determined, which was more than five times higher than the initial value.

Keywords: chemical grout, expanding polyurethane resin, foundation remediation, ground improvement

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Authors: Habib Muhammetoglu, I. Ethem Karadirek, Selami Kara, Ayse Muhammetoglu

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The problem of non-revenue water (NRW) from municipal water distribution networks is common in many countries such as Turkey, where the average yearly water losses are around 50% . Water losses can be divided into two major types namely: 1) Real or physical water losses, and 2) Apparent or commercial water losses. Total water losses in Antalya city, Turkey is around 45%. Methods: A research study was conducted to develop appropriate methodologies to reduce NRW. A pilot study area of about 60 thousands inhabitants was chosen to apply the study. The pilot study area has a supervisory control and data acquisition (SCADA) system for the monitoring and control of many water quantity and quality parameters at the groundwater drinking wells, pumping stations, distribution reservoirs, and along the water mains. The pilot study area was divided into 18 District Metered Areas (DMAs) with different number of service connections that ranged between a few connections to less than 3000 connections. The flow rate and water pressure to each DMA were on-line continuously measured by an accurate flow meter and water pressure meter that were connected to the SCADA system. Customer water meters were installed to all billed and unbilled water users. The monthly water consumption as given by the water meters were recorded regularly. Water balance was carried out for each DMA using the well-know standard IWA approach. There were considerable variations in the water losses percentages and the components of the water losses among the DMAs of the pilot study area. Old Class B customer water meters at one DMA were replaced by more accurate new Class C water meters. Hydraulic modelling using the US-EPA EPANET model was carried out in the pilot study area for the prediction of water pressure variations at each DMA. The data sets required to calibrate and verify the hydraulic model were supplied by the SCADA system. It was noticed that a number of the DMAs exhibited high water pressure values. Therefore, pressure reducing valves (PRV) with constant head were installed to reduce the pressure up to a suitable level that was determined by the hydraulic model. On the other hand, the hydraulic model revealed that the water pressure at the other DMAs cannot be reduced when complying with the minimum pressure requirement (3 bars) as stated by the related standards. Results: Physical water losses were reduced considerably as a result of just reducing water pressure. Further physical water losses reduction was achieved by applying acoustic methods. The results of the water balances helped in identifying the DMAs that have considerable physical losses. Many bursts were detected especially in the DMAs that have high physical water losses. The SCADA system was very useful to assess the efficiency level of this method and to check the quality of repairs. Regarding apparent water losses reduction, changing the customer water meters resulted in increasing water revenue by more than 20%. Conclusions: DMA, SCADA, modelling, pressure management, leakage detection and accurate customer water meters are efficient for NRW.

Keywords: NRW, water losses, pressure management, SCADA, apparent water losses, urban water distribution networks

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Authors: Fereshteh Chekin, Sepideh Sadeghi

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Nickel nanoparticles have attracted much attention because of applications in catalysis, medical diagnostics and magnetic applications. In this work, we reported a simple and low-cost procedure to synthesize nickel oxide nanoparticles (NiO-NPs) by using sodium dodecyl sulphate (SDS) and gelatin as stabilizer. The synthesized NiO-NPs were characterized by a variety of means such as transmission electron microscope (TEM), powder X-ray diffraction (XRD), scanning electron microscope (SEM) and UV-vis spectroscopy. The results show that the NiO nanoparticles with high crystalline can be obtained using this simple method. The grain size measured by TEM was 16 in presence of SDS, which agrees well with the XRD data. SDS plays an important role in the formation of the NiO nanoparticles. Moreover, the NiO nanoparticles have been used as a solid phase catalyst for the decomposition of hydrazine hydrate at room temperatures. The decomposition process has been monitored by UV–vis analysis. The present study showed that nanoparticles are not poisoned after their repeated use in decomposition of hydrazine.

Keywords: nickel oxide nanoparticles, sodium dodecyl sulphate, synthesis, stabilizer

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Authors: Y. H. Hwang, J. Won, Y. S. Kang

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Since ionic liquids have a special interaction with gas specially CO2 and/or olefin, supported ionic liquids membrane (SILM) are fabricated for practical gas separation. However, SILM has a problem in practical application due to the low mechanical stability under high pressure for gas separation. In order to improve the mechanical strength of the selective ionic liquid layer, we prepared supported ion gel membrane by the formation of gel on the surface of Nylon support. The ion gel was prepared by the addition of poly(styrene-block-ethyleneoxide-block-styrene) triblock copolymer in four tricyanomethanide ionic liquids have different cation; 1-ethyl-3-methlyimidazolium tricyanomethanide, 1-butyl-3-methlyimidazolium tricyanomethanide, 1-butyl-1-methylpyrrolidinium tricyanomethanide, 1-butyl-4-methylpyridinium tricyanomethanide using methylenechloride as a solvent. The characters of ion gel with different cation were studied. Four different gases (CO2, N2, O2, and CH4) permeance were measured at room temperature by bubble flow meter and cation effect of tricyanomethanide ionic liquids investigated.

Keywords: membrane, ionic liquid, ion gel, nanostructure

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Authors: G. Baraneedaran, Deepak Singh, Kollipara Tejesh

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The wireless sensors network has been an active research area over the y-ear passed. Due to the limited energy and communication ability of sensor nodes, it seems especially important to design a routing protocol for WSNs so that sensing data can be transmitted to the receiver effectively, an energy-balanced routing method based on forward-aware factor (FAF-EBRM) is proposed in this paper. In FAF-EBRM, the next-hop node is selected according to the awareness of link weight and forward energy density. A spontaneous reconstruction mechanism for Local topology is designed additionally. In this experiment, FAF-EBRM is compared with LEACH and EECU, experimental results show that FAF-EBRM outperforms LEACH and EECU, which balances the energy consumption, prolongs the function lifetime and guarantees high Qos of WSN.

Keywords: energy balance, forward-aware factor (FAF), forward energy density, link weight, network performance

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Authors: Nayana T. Nivangune, Vivek V. Ranade, Ashutosh A. Kelkar

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Organic carbamates are versatile compounds widely employed as pesticides, fungicides, herbicides, dyes, pharmaceuticals, cosmetics and in the synthesis of polyurethanes. Carbamates can be easily transformed into isocyanates by thermal cracking. Isocyantes are used as precursors for manufacturing agrochemicals, adhesives and polyurethane elastomers. Manufacture of polyurethane foams is a major application of aromatic ioscyanates and in 2007 the global consumption of polyurethane was about 12 million metric tons/year and the average annual growth rate was about 5%. Presently Isocyanates/carbamates are manufactured by phosgene based process. However, because of high toxicity of phoegene and formation of waste products in large quantity; there is a need to develop alternative and safer process for the synthesis of isocyanates/carbamates. Recently many alternative processes have been investigated and carbamate synthesis by methoxycarbonylation of aromatic amines using dimethyl carbonate (DMC) as a green reagent has emerged as promising alternative route. In this reaction methanol is formed as a by-product, which can be converted to DMC either by oxidative carbonylation of methanol or by reacting with urea. Thus, the route based on DMC has a potential to provide atom efficient and safer route for the synthesis of carbamates from DMC and amines. Lot of work is being carried out on the development of catalysts for this reaction and homogeneous zinc salts were found to be good catalysts for the reaction. However, catalyst/product separation is challenging with these catalysts. There are few reports on the use of supported Zn catalysts; however, deactivation of the catalyst is the major problem with these catalysts. We wish to report here methoxycarbonylation of aniline to methylphenylcarbamate (MPC) using amino acid complexes of Zn as highly active and selective catalysts. The catalysts were characterized by XRD, IR, solid state NMR and XPS analysis. Methoxycarbonylation of aniline was carried out at 170 °C using 2.5 wt% of the catalyst to achieve >98% conversion of aniline with 97-99% selectivity to MPC as the product. Formation of N-methylated products in small quantity (1-2%) was also observed. Optimization of the reaction conditions was carried out using zinc-proline complex as the catalyst. Selectivity was strongly dependent on the temperature and aniline:DMC ratio used. At lower aniline:DMC ratio and at higher temperature, selectivity to MPC decreased (85-89% respectively) with the formation of N-methylaniline (NMA), N-methyl methylphenylcarbamate (MMPC) and N,N-dimethyl aniline (NNDMA) as by-products. Best results (98% aniline conversion with 99% selectivity to MPC in 4 h) were observed at 170oC and aniline:DMC ratio of 1:20. Catalyst stability was verified by carrying out recycle experiment. Methoxycarbonylation preceded smoothly with various amine derivatives indicating versatility of the catalyst. The catalyst is inexpensive and can be easily prepared from zinc salt and naturally occurring amino acids. The results are important and provide environmentally benign route for MPC synthesis with high activity and selectivity.

Keywords: aniline, heterogeneous catalyst, methoxycarbonylation, methylphenyl carbamate

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Authors: Meena Marafi, Mohan S. Rana

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Catalysts play an important role in producing valuable fuel products in petroleum refining; but, due to feedstock’s impurities catalyst gets deactivated with carbon and metal deposition. The disposal of spent catalyst falls under the category of hazardous industrial waste that requires strict agreement with environmental regulations. The spent hydroprocessing catalyst contains Mo, V and Ni at high concentrations that have been found to be economically significant for recovery. Metal recovery process includes deoiling, decoking, grinding, dissolving and treatment with complexing leaching agent such as ethylene diamine tetra acetic acid (EDTA). The process conditions have been optimized as a function of time, temperature and EDTA concentration in presence of ultrasonic agitation. The results indicated that optimum condition established through this approach could recover 97%, 94% and 95% of the extracted Mo, V and Ni, respectively, while 95% EDTA was recovered after acid treatment.

Keywords: atmospheric residue desulfurization (ARDS), deactivation, hydrotreating, spent catalyst

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Authors: Inalegwu Stephany Akipu

Abstract:

Archaeology being the study of mans past using the materials he left behind has been argued to be classified under sciences while some scholars are of the opinion that it does not deserve the status of being referred to as ‘science’. However divergent the opinions of scholars may be on the classification of Archaeology as a science or in the humanities, the discipline has no doubt, greatly aided in shaping the history of man’s past. Through the different stages that the discipline has transgressed, it has encountered some challenges. This paper therefore, attempts to highlight the need for the inclusion of branches of other disciplines when using Archaeology in reconstructing man’s history. The objective of course, is to add to the existing body of knowledge but specifically to expose the incomparable importance of archaeology as a discipline and to place it on such a high scale that it will not be regulated to the background as is done in some Nigerian Universities. The paper attempts a clarification of some conceptual terms and discusses the developmental stages of archaeology. It further describes the present state of the discipline and concludes with the disciplines that need to be imbibed in the use of Archaeology which is an evolving cultural science to obtain the aforementioned interdisciplinary approach.

Keywords: archaeology, cultural, evolution, interdisciplinary, science

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Authors: Matthew O. Ikuabe, Ayodeji E. Oke, Clinton O. Aigbavboa, Douglas O. Aghimien

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The use of technological innovations have been touted to be beneficial in the delivery of construction projects. Particularly, Radio Frequency Identification (RFID) technology is widely regarded to be of immense advantage for the management of construction projects. This study focused on evaluating the barriers to the use of Radio Frequency Identification (RFID) technology for the delivery of construction projects. Using Gauteng Provincein South Africa as the study area, questionnaire was used in eliciting responses from construction professionals, which made up the population of the study. Retrieved data was analysed using Mean Item Score and One-Sample t-test. Findings from the study showed that the most significant barriers to the deployment of RFID for construction project delivery are high cost and lack of awareness. Conclusively, the study made recommendations that would aid in the abatement of the barriers to the use of RFID technology for construction project delivery.

Keywords: barriers, construction, project delivery, RFID

Procedia PDF Downloads 185