Search results for: fractional edge domination number
8963 Determination of Optimum Parameters for Thermal Stress Distribution in Composite Plate Containing a Triangular Cutout by Optimization Method
Authors: Mohammad Hossein Bayati Chaleshtari, Hadi Khoramishad
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Minimizing the stress concentration around triangular cutout in infinite perforated plates subjected to a uniform heat flux induces thermal stresses is an important consideration in engineering design. Furthermore, understanding the effective parameters on stress concentration and proper selection of these parameters enables the designer to achieve a reliable design. In the analysis of thermal stress, the effective parameters on stress distribution around cutout include fiber angle, flux angle, bluntness and rotation angle of the cutout for orthotropic materials. This paper was tried to examine effect of these parameters on thermal stress analysis of infinite perforated plates with central triangular cutout. In order to achieve the least amount of thermal stress around a triangular cutout using a novel swarm intelligence optimization technique called dragonfly optimizer that inspired by the life method and hunting behavior of dragonfly in nature. In this study, using the two-dimensional thermoelastic theory and based on the Likhnitskiiʼ complex variable technique, the stress analysis of orthotropic infinite plate with a circular cutout under a uniform heat flux was developed to the plate containing a quasi-triangular cutout in thermal steady state condition. To achieve this goal, a conformal mapping function was used to map an infinite plate containing a quasi- triangular cutout into the outside of a unit circle. The plate is under uniform heat flux at infinity and Neumann boundary conditions and thermal-insulated condition at the edge of the cutout were considered.Keywords: infinite perforated plate, complex variable method, thermal stress, optimization method
Procedia PDF Downloads 1478962 Promotional Effects of Zn in Cu-Zn/Core-Shell Al-MCM-41 for Selective Catalytic Reduction of NO with NH3: Acidic Properties, NOx Adsorption Properties, and Nature of Copper
Authors: Thidarat Imyen, Paisan Kongkachuichay
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Cu-Zn/core-shell Al-MCM-41 catalyst with various copper species, prepared by a combination of three methods—substitution, ion-exchange, and impregnation, was studied for the selective catalytic reduction (SCR) of NO with NH3 at 300 °C for 150 min. In order to investigate the effects of Zn introduction on the nature of the catalyst, Cu/core-shell Al-MCM-41 and Zn/core-shell Al-MCM-41 catalysts were also studied. The roles of Zn promoter in the acidity and the NOx adsorption properties of the catalysts were investigated by in situ Fourier transform infrared spectroscopy (FTIR) of NH3 and NOx adsorption, and temperature-programmed desorption (TPD) of NH3 and NOx. The results demonstrated that the acidity of the catalyst was enhanced by the Zn introduction, as exchanged Zn(II) cations loosely bonded with Al-O-Si framework could create Brønsted acid sites by interacting with OH groups. Moreover, Zn species also provided the additional sites for NO adsorption in the form of nitrite (NO2–) and nitrate (NO3–) species, which are the key intermediates for SCR reaction. In addition, the effect of Zn on the nature of copper was studied by in situ FTIR of CO adsorption and in situ X-ray adsorption near edge structure (XANES). It was found that Zn species hindered the reduction of Cu(II) to Cu(0), resulting in higher Cu(I) species in the Zn promoted catalyst. The Cu-Zn/core-shell Al-MCM-41 exhibited higher catalytic activity compared with that of the Cu/core-shell Al-MCM-41 for the whole reaction time, as it possesses the highest amount of Cu(I) sites, which are responsible for SCR catalytic activity. The Cu-Zn/core-shell Al-MCM-41 catalyst also reached the maximum NO conversion of 100% with the average NO conversion of 76 %. The catalytic performance of the catalyst was further improved by using Zn promoter in the form of ZnO instead of reduced Zn species. The Cu-ZnO/core-shell Al-MCM-41 catalyst showed better catalytic performance with longer working reaction time, and achieved the average NO conversion of 81%.Keywords: Al-MCM-41, copper, nitrogen oxide, selective catalytic reduction, zinc
Procedia PDF Downloads 3028961 The Impact of Failure-tolerant Restaurant Culture on Curbing Employees’ Withdrawal Behavior: The Roles of Psychological Empowerment and Mindful Leadership
Authors: Omar Alsetoohy, Mohamed Ezzat, Mahmoud Abou Kamar
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The success of a restaurant or hotel depends very much on the quality and quantity of its human resources. Thus, establishing a competitive edge through human assets requires careful attention to the practices that best leverage these assets. Usually, hotel or restaurant employees recognize customer defection as an unfavorable or unpleasant occurrence associated with failure. These failures could be in handling, communication, learning, or encouragement. Besides, employees could be afraid of blame from their colleagues and managers, which prevents them from freely discussing these mistakes with them. Such behaviors, in turn, would push employees to withdraw from the workplace. However, we have a good knowledge of the leadership outcomes, but less is known about how and why these effects occur. Accordingly, mindful leaders usually analyze the causes and underlying mechanisms of failures for work improvement. However, despite the excessive literature in the field of leadership and employee behaviors, to date, no research studies had investigated the impact of a failure-tolerant restaurant culture on the employees’ withdrawal behaviors considering the moderating role of psychological empowerment and mindful leadership. Thus, this study seeks to investigate the impact of a failure-tolerant culture on the employees’ withdrawal behaviors in fast-food restaurants in Egypt considering the moderating effects of employee empowerment and mindful leaders. This study may contribute to the existing literature by filling the gap between failure-tolerant cultures and employee withdrawal behaviors in the hospitality literature. The study may also identify the best practices for restaurant operators and managers to deal with employees' failures as an improvement tool for their performance.Keywords: failure-tolerant culture, employees’ withdrawal behaviors psychological empowerment, mindful leadership, restaurants
Procedia PDF Downloads 1088960 Characterization of Laminar Flow and Power Consumption in Agitated Vessel with Curved Blade Agitator
Authors: Amine Benmoussa, Mohamed Bouanini, Mebrouk Rebhi
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Stirring is one of the unifying processes which form part of the mechanical unit operations in process technology such chemical, biotechnological, pharmaceutical, petrochemical, cosmetic, and food processing. Therefore determining the level of mixing and overall behavior and performance of the mixing tanks are crucial from the product quality and process economics point of views. The most fundamental needs for the analysis of these processes from both a theoretical and industrial perspective are the knowledge of the hydrodynamic behavior and the flow structure in such tanks. Depending on the purpose of the operation carried out in mixer, the best choice for geometry of the tank and agitator type can vary widely. Initially, a local and global study namely the velocity and power number on a typical agitation system agitated by a mobile-type two-blade straight (d/D=0.5) allowed us to test the reliability of the CFD, the result were compared with those of experimental literature, a very good concordance was observed. The stream function, the velocity profile, the velocity fields and power number are analyzed. It was shown that the hydrodynamics is modified by the curvature of the mobile which plays a key role.Keywords: agitated vessels, curved blade agitator, laminar flow, finite volume method
Procedia PDF Downloads 2848959 Unsteady Natural Convection in a Square Cavity Partially Filled with Porous Media Using a Thermal Non-Equilibrium Model
Authors: Ammar Alsabery, Habibis Saleh, Norazam Arbin, Ishak Hashim
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Unsteady natural convection and heat transfer in a square cavity partially filled with porous media using a thermal non-equilibrium model is studied in this paper. The left vertical wall is maintained at a constant hot temperature and the right vertical wall is maintained at a constant cold temperature, while the horizontal walls are adiabatic. The governing equations are obtained by applying the Darcy model and Boussinesq approximation. COMSOL's finite element method is used to solve the non-dimensional governing equations together with specified boundary conditions. The governing parameters of this study are the Rayleigh number, the modified thermal conductivity ratio, the inter-phase heat transfer coefficien and the time independent. The results presented for values of the governing parameters in terms of streamlines in both fluid/porous layer, isotherms of fluid and solid porous layer, isotherms of fluid layer, and average Nusselt number.Keywords: unsteady natural convection, thermal non-equilibrium model, Darcy model
Procedia PDF Downloads 3768958 Numerical Study of Heat Transfer and Laminar Flow over a Backward Facing Step with and without Obstacle
Authors: Hussein Togun, Tuqa Abdulrazzaq, S. N. Kazi, A. Badarudin, M. K. A. Ariffin, M. N. M. Zubir
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Heat transfer and laminar fluid flow over backward facing step with and without obstacle numerically studied in this paper. The finite volume method adopted to solve continuity, momentum and energy equations in two dimensions. Backward facing step without obstacle and with different dimension of obstacle were presented. The step height and expansion ratio of channel were 4.8mm and 2 respectively, the range of Reynolds number varied from 75 to 225, constant heat flux subjected on downstream of wall was 2000W/m2, and length of obstacle was 1.5, 3, and 4.5mm with width 1.5mm. The separation length noticed increase with increase Reynolds number and height of obstacle. The result shows increase of heat transfer coefficient for backward facing step with obstacle in compared to those without obstacle. The maximum enhancement of heat transfer observed at 4.5mm of height obstacle due to increase recirculation flow after the obstacle in addition that at backward. Streamline of velocity showing the increase of recirculation region with used obstacle in compared without obstacle and highest recirculation region observed at obstacle height 4.5mm. The amount of enhancement heat transfer was varied between 3-5% compared to backward without obstacle.Keywords: separation flow, backward facing step, heat transfer, laminar flow
Procedia PDF Downloads 4698957 Feedback from Experiments on Managing Methods against Japanese Knotweed on a River Appendix of the RhôNe between 2015 and 2020
Authors: William Brasier, Nicolas Rabin, Celeste Joly
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Japanese knotweed (Fallopia japonica) is very present on the banks of the Rhone, colonizing more and more areas along the river. The Compagnie Nationale du Rhone (C.N.R.), which manages the river, has experimented with several control techniques in recent years. Since 2015, 15 experimental plots have been monitored on the banks of a restored river appendix to measure the effect of three control methods: confinement by felt, repeated mowing and the planting of competing species and/or species with allelopathic power: Viburnum opulus, Rhamnus frangula, Sambucus ebulus and Juglans regia. Each year, the number of stems, the number of elderberry plants, the height of the plants and photographs were collected. After six years of monitoring, the results showed that the density of knotweed stems decreased by 50 to 90% on all plots. The control methods are sustainable and are gradually gaining in efficiency. The establishment of native plants coupled with regular manual maintenance can reduce the development of Japanese knotweed. Continued monitoring over the next few years will determine the kinetics of the total eradication (i.e. 0 stem/plot) of the Japanese knotweed by these methods.Keywords: fallopia japonica, interspecific plant competition , Rhone river, riparian trees
Procedia PDF Downloads 1328956 A Fuzzy TOPSIS Based Model for Safety Risk Assessment of Operational Flight Data
Authors: N. Borjalilu, P. Rabiei, A. Enjoo
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Flight Data Monitoring (FDM) program assists an operator in aviation industries to identify, quantify, assess and address operational safety risks, in order to improve safety of flight operations. FDM is a powerful tool for an aircraft operator integrated into the operator’s Safety Management System (SMS), allowing to detect, confirm, and assess safety issues and to check the effectiveness of corrective actions, associated with human errors. This article proposes a model for safety risk assessment level of flight data in a different aspect of event focus based on fuzzy set values. It permits to evaluate the operational safety level from the point of view of flight activities. The main advantages of this method are proposed qualitative safety analysis of flight data. This research applies the opinions of the aviation experts through a number of questionnaires Related to flight data in four categories of occurrence that can take place during an accident or an incident such as: Runway Excursions (RE), Controlled Flight Into Terrain (CFIT), Mid-Air Collision (MAC), Loss of Control in Flight (LOC-I). By weighting each one (by F-TOPSIS) and applying it to the number of risks of the event, the safety risk of each related events can be obtained.Keywords: F-topsis, fuzzy set, flight data monitoring (FDM), flight safety
Procedia PDF Downloads 1688955 Numerical Modeling of a Molten Salt Power Tower Configuration Adaptable for Harsh Winter Climate
Authors: Huiqiang Yang, Domingo Santana
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This paper proposes a novel configuration which introduces a natural draft dry cooling tower system in a molten salt power tower. A three-dimensional numerical modeling was developed based on the novel configuration. A plan of building 20 new concentrating solar power plants has been announced by Chinese government in September 2016, and among these 20 new plants, most of them are located in regions with long winter and harsh winter climate. The innovative configuration proposed includes an external receiver concrete tower at the center, a natural draft dry cooling tower which is surrounding the external receiver concrete tower and whose shell is fixed on the external receiver concrete tower, and a power block (including a steam generation system, a steam turbine system and hot/cold molten salt tanks, and water treatment systems) is covered by the roof of the natural draft dry cooling tower. Heat exchanger bundles are vertically installed at the furthest edge of the power block. In such a way, all power block equipment operates under suitable environmental conditions through whole year operation. The monthly performance of the novel configuration is simulated as compared to a standard one. The results show that the novel configuration is much more efficient in each separate month in a typical meteorological year. Moreover, all systems inside the power block have less thermal losses at low ambient temperatures, especially in harsh winter climate. It is also worthwhile mentioning that a photovoltaic power plant can be installed on the roof of the cooling tower to reduce the parasites of the molten salt power tower.Keywords: molten salt power tower, natural draft dry cooling, commercial scale, power block, harsh winter climate
Procedia PDF Downloads 3418954 Dynamic Modeling of the Green Building Movement in the U.S.: Strategies to Reduce Carbon Footprint of Residential Building Stock
Authors: Nuri Onat, Omer Tatari, Gokhan Egilmez
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The U.S. buildings consume significant amount of energy and natural resources and they are responsible for approximately 40 % of the greenhouse gases emitted in the United States. Awareness of these environmental impacts paved the way for the adoption of green building movement. The green building movement is a rapidly increasing trend. Green Construction market has generated $173 billion dollars in GDP, supported over 2.4 million jobs, and provided $123 billion dollars in labor earnings. The number of LEED certified buildings is projected to be almost half of the all new, nonresidential buildings by 2015. National Science and Technology Council (NSTC) aims to increase number of net-zero energy buildings (NZB). The ultimate goal is to have all commercial NZB by 2050 in the US (NSTC 2008). Green Building Initiative (GBI) became the first green building organization that is accredited by American National Standards Institute (ANSI), which will also boost number of green buildings certified by Green Globes. However, there is much less focus on greening the residential buildings, although the environmental impacts of existing residential buildings are more than that of commercial buildings. In this regard, current research aims to model the residential green building movement with a dynamic model approach and assess the possible strategies to stabilize the carbon footprint of the U.S. residential building stock. Three aspects of sustainable development are considered in policy making, namely: high performance green building (HPGB) construction, NZB construction and building retrofitting. 19 different policy options are proposed and analyzed. Results of this study explored that increasing the construction rate of HPGBs or NZBs is not a sufficient policy to stabilize the carbon footprint of the residential buildings. Energy efficient building retrofitting options are found to be more effective strategies then increasing HPGBs and NZBs construction. Also, significance of shifting to renewable energy sources for electricity generation is stressed.Keywords: green building movement, residential buildings, carbon footprint, system dynamics
Procedia PDF Downloads 4288953 International Student Mobility to China: A Fastest and Emerging Market for International Students among Developing Countries
Authors: Yasir Khan, Qiu Bin, Antonio-Mihi Ramirez
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This study determines the inflow of international students to China in recent years and the corresponding internationalization strategies in the higher education sector. China has placed attracting international students on in its plan along with the growing of global impact. Acknowledging the stable economy, growth rate, trade, lower renminbi rate, high wages, employment opportunities, high level income per capita, relative low taxes and political system consolidate to attract more international students. A large number of international students making a vast contribution to the higher education sector of China. Understanding the significance of education mission as well as of financial ‘bottom line’ the Chinese government gave great importance to invite more international students from worldwide. The large number of international students in the China has been particularly notable from Asian countries specifically neighboring countries, Pakistan, Thailand, India, Vietnam, South Korea, Magnolia, Malaysia, and Russia. This study summarizes internationalization of higher education in China and also provides directions for future research in this regard.Keywords: international student mobility, 2020 Govt Planning, emerging market, internationalization of higher education
Procedia PDF Downloads 2528952 A Review on Thermal Conductivity of Bio-Based Carbon Nanotubes
Authors: Gloria A. Adewumi, Andrew C. Eloka-Eboka, Freddie L. Inambao
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Bio-based carbon nanotubes (CNTs) have received considerable research attention due to their comparative advantages of high level stability, simplistic use, low toxicity and overall environmental friendliness. New potentials for improvement in heat transfer applications are presented due to their high aspect ratio, high thermal conductivity and special surface area. Phonons have been identified as being responsible for thermal conductivities in carbon nanotubes. Therefore, understanding the mechanism of heat conduction in CNTs involves investigating the difference between the varieties of phonon modes and knowing the kinds of phonon modes that play the dominant role. In this review, a reference to a different number of studies is made and in addition, the role of phonon relaxation rate mainly controlled by boundary scattering and three-phonon Umklapp scattering process was investigated. Results show that the phonon modes are sensitive to a number of nanotube conditions such as: diameter, length, temperature, defects and axial strain. At a low temperature (<100K) the thermal conductivity increases with increasing temperature. A small nanotube size causes phonon quantization which is evident in the thermal conductivity at low temperatures.Keywords: carbon nanotubes, phonons, thermal conductivity, Umklapp process
Procedia PDF Downloads 3608951 Adhesion of Biofilm to Surfaces Employed in Pipelines for Transporting Crude Oil
Authors: Hadjer Didouh, Izzaddine Sameut Bouhaik, Mohammed Hadj Meliani
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This research delves into the intricate dynamics of biofilm adhesion on surfaces, particularly focusing on the widely employed X52 surface in oil and gas industry pipelines. Biofilms, characterized by microorganisms within a self-produced matrix, pose significant challenges due to their detrimental impact on surfaces. Our study integrates advanced molecular techniques and cutting-edge microscopy, such as scanning electron microscopy (SEM), to identify microbial communities and visually assess biofilm adhesion. Simultaneously, we concentrate on the X52 surface, utilizing impedance spectroscopy and potentiodynamic polarization to gather electrochemical responses under various conditions. In conjunction with the broader investigation, we propose a novel approach to mitigate biofilm-induced corrosion challenges. This involves environmentally friendly inhibitors derived from plants, offering a sustainable alternative to conventional chemical treatments. Our inquiry screens and selects inhibitors based on their efficacy in hindering biofilm formation and reducing corrosion rates on the X52 surface. This study contributes valuable insights into the interplay between electrochemical processes and biofilm attachment on the X52 surface. Furthermore, the outcomes of this research have broader implications for the oil and gas industry, where biofilm-related corrosion is a persistent concern. The exploration of eco-friendly inhibitors not only holds promise for corrosion control but also aligns with environmental considerations and sustainability goals. The comprehensive nature of this research aims to enhance our understanding of biofilm dynamics, provide effective strategies for corrosion mitigation, and contribute to sustainable practices in pipeline management within the oil and gas sector.Keywords: bio-corrosion, biofilm, attachment, X52, metal/bacteria interface
Procedia PDF Downloads 478950 Changes in Foreign Direct Investment Policy of India and Its Impact on Economic Development
Authors: Kishor P. Kadam
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Foreign direct investment policy (FDI) is defined as an investment involving a long term relationship and reflecting a long duration interest and control of a resident entity in the home country (foreign direct investor or parent firm) in the host country. India has been one of the most translucent and open-minded FDI regimes among the emerging and developing economies. There is clear cut mentioned about the sectoral caps for foreign investment. The policy problems that have been identified by time to time surveys as acting as additional hurdles for FDI are laws, regulatory systems and government monopolies that do not have contemporary relevance. Foreign investment policies in the post-reforms period have emphasized greater encouragement and mobilization of non-debt creating private inflows for plunging reliance on debt flows. This paper will focus on how foreign direct investment policy changed from 1990-91 up to now. A time series data of 25 years is used for analysing the policy changes. It is observed that India has more liberal policy. The growth in number of Greenfield investments in India has been more impressive than the number of M&A deals whereas equity capital for incorporated bodies FDI inflows has been increased continuously 2014-15. India has made major changes in FDI Policy, and it has positive impact on economic development.Keywords: FDI, India, economic development, government
Procedia PDF Downloads 3618949 Optimizing Data Integration and Management Strategies for Upstream Oil and Gas Operations
Authors: Deepak Singh, Rail Kuliev
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The abstract highlights the critical importance of optimizing data integration and management strategies in the upstream oil and gas industry. With its complex and dynamic nature generating vast volumes of data, efficient data integration and management are essential for informed decision-making, cost reduction, and maximizing operational performance. Challenges such as data silos, heterogeneity, real-time data management, and data quality issues are addressed, prompting the proposal of several strategies. These strategies include implementing a centralized data repository, adopting industry-wide data standards, employing master data management (MDM), utilizing real-time data integration technologies, and ensuring data quality assurance. Training and developing the workforce, “reskilling and upskilling” the employees and establishing robust Data Management training programs play an essential role and integral part in this strategy. The article also emphasizes the significance of data governance and best practices, as well as the role of technological advancements such as big data analytics, cloud computing, Internet of Things (IoT), and artificial intelligence (AI) and machine learning (ML). To illustrate the practicality of these strategies, real-world case studies are presented, showcasing successful implementations that improve operational efficiency and decision-making. In present study, by embracing the proposed optimization strategies, leveraging technological advancements, and adhering to best practices, upstream oil and gas companies can harness the full potential of data-driven decision-making, ultimately achieving increased profitability and a competitive edge in the ever-evolving industry.Keywords: master data management, IoT, AI&ML, cloud Computing, data optimization
Procedia PDF Downloads 708948 Estimation of Energy Losses of Photovoltaic Systems in France Using Real Monitoring Data
Authors: Mohamed Amhal, Jose Sayritupac
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Photovoltaic (PV) systems have risen as one of the modern renewable energy sources that are used in wide ranges to produce electricity and deliver it to the electrical grid. In parallel, monitoring systems have been deployed as a key element to track the energy production and to forecast the total production for the next days. The reliability of the PV energy production has become a crucial point in the analysis of PV systems. A deeper understanding of each phenomenon that causes a gain or a loss of energy is needed to better design, operate and maintain the PV systems. This work analyzes the current losses distribution in PV systems starting from the available solar energy, going through the DC side and AC side, to the delivery point. Most of the phenomena linked to energy losses and gains are considered and modeled, based on real time monitoring data and datasheets of the PV system components. An analysis of the order of magnitude of each loss is compared to the current literature and commercial software. To date, the analysis of PV systems performance based on a breakdown structure of energy losses and gains is not covered enough in the literature, except in some software where the concept is very common. The cutting-edge of the current analysis is the implementation of software tools for energy losses estimation in PV systems based on several energy losses definitions and estimation technics. The developed tools have been validated and tested on some PV plants in France, which are operating for years. Among the major findings of the current study: First, PV plants in France show very low rates of soiling and aging. Second, the distribution of other losses is comparable to the literature. Third, all losses reported are correlated to operational and environmental conditions. For future work, an extended analysis on further PV plants in France and abroad will be performed.Keywords: energy gains, energy losses, losses distribution, monitoring, photovoltaic, photovoltaic systems
Procedia PDF Downloads 1768947 Heat Transfer Enhancement Due to the Optimal Porosity in Plate Heat Exchangers with Sinusoidal Plates
Authors: Hossein Shokouhmand, Seyyed Mostafa Saadat
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In this paper, the effect of thermal dispersion on the performance of plate heat exchangers (PHEs) with sinusoidal plates is investigated. In this regard, the PHE is considered as a porous medium. The important property of a porous medium is porosity that is defined as the total fluid volume divided by the total volume occupied by the solid and fluid. A 2D array of parallel sinusoidal plates with laminar periodically developed forced convection and single-phase constant property flows and conduction in a homogenous solid phase in two directions is considered. The array of flows is counter and the flows heat capacities are equal. Numerical study of conjugate heat transfer and axial conduction in the solid phase with different plate thicknesses showed that there is an optimal porosity in which the efficiency of heat transfer is up to 4% more than the time when the porosity is near one. It is shown that the optimal porosity at zero angle of inclination depends both on Reynolds number and the aspect ratio. The optimal porosity increased while either the Reynolds number or waviness of plates increased.Keywords: plate heat exchanger, optimal porosity, efficiency, aspect ratio
Procedia PDF Downloads 4058946 The Environmental Effects of Amalgam Tooth Fillings
Authors: Abdulsalam I. Rafida, Abdulhmid M. Alkout, Abdultif M. Alroba
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This study investigates the heavy metal content in the saliva of persons with amalgam tooth fillings. For this purpose, samples of saliva have been collected based on two factors i.e. the number of amalgam fillings in the mouth (one, two or three fillings), and the time factor i.e. the time since the fillings have been in place (less than a year and more than a year). Samples of saliva have also been collected from persons with no amalgam tooth fillings for control. The samples that have been collected so far, have been examined for the basic heavy metal content featuring amalgam, which include mercury (Hg) and silver (Ag). However, all the above mentioned elements have been detected in the samples of saliva of the persons with amalgam tooth fillings, though with varying amounts depending on the number of fillings. Thus, for persons with only one filling the average quantities were found to be 0.00061 ppm and 0.033 ppm for Hg and Ag respectively. On the other hand for persons with two fillings the average quantities were found to be 0.0012 ppm and 0.029 ppm for each of the two elements respectively. However, in order to understand the chemical reactions associated with amalgam tooth fillings in the mouth, the material have been treated outside the mouth using some nutrient media. Those media included drinking water, fizzy drinks and hot tea. All three media have been found to contain the three elements after amalgam treatment. Yet, the fizzy drink medium was found to contain the highest levels of those elements.Keywords: amalgam, mercury, silver, fizzy drinks, media
Procedia PDF Downloads 1978945 Single Cell Sorter Driven by Resonance Vibration of Cell Culture Substrate
Authors: Misa Nakao, Yuta Kurashina, Chikahiro Imashiro, Kenjiro Takemura
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The Research Goal: With the growing demand for regenerative medicine, an effective mass cell culture process is required. In a repetitive subculture process for proliferating cells, preparing single cell suspension which does not contain any cell aggregates is highly required because cell aggregates often raise various undesirable phenomena, e.g., apoptosis and decrease of cell proliferation. Since cell aggregates often occur in cell suspension during conventional subculture processes, this study proposes a single cell sorter driven by a resonance vibration of a cell culture substrate. The Method and the Result: The single cell sorter is simply composed of a cell culture substrate and a glass pipe vertically placed against the cell culture substrate with a certain gap corresponding to a cell diameter. The cell culture substrate is made of biocompatible stainless steel with a piezoelectric ceramic disk glued to the bottom side. Applying AC voltage to the piezoelectric ceramic disk, an out-of-plane resonance vibration with a single nodal circle of the cell culture substrate can be excited at 5.5 kHz. By doing so, acoustic radiation force is emitted, and then cell suspension containing only single cells is pumped into the pipe and collected. This single cell sorter is effective to collect single cells selectively in spite of its quite simple structure. We collected C2C12 myoblast cell suspension by the single cell sorter with the vibration amplitude of 12 µmp-p and evaluated the ratio of single cells in number against the entire cells in the suspension. Additionally, we cultured the collected cells for 72 hrs and measured the number of cells after the cultivation in order to evaluate their proliferation. As a control sample, we also collected cell suspension by conventional pipetting, and evaluated the ratio of single cells and the number of cells after the 72-hour cultivation. The ratio of single cells in the cell suspension collected by the single cell sorter was 98.2%. This ratio was 9.6% higher than that collected by conventional pipetting (statistically significant). Moreover, the number of cells cultured for 72 hrs after the collection by the single cell sorter yielded statistically more cells than that collected by pipetting, resulting in a 13.6% increase in proliferated cells. These results suggest that the cell suspension collected by the single cell sorter driven by the resonance vibration hardly contains cell aggregates whose diameter is larger than the gap between the cell culture substrate and the pipe. Consequently, the cell suspension collected by the single cell sorter maintains high cell proliferation. Conclusions: In this study, we developed a single cell sorter capable of sorting and pumping single cells by a resonance vibration of a cell culture substrate. The experimental results show the single cell sorter collects single cell suspension which hardly contains cell aggregates. Furthermore, the collected cells show higher proliferation than that of cells collected by conventional pipetting. This means the resonance vibration of the cell culture substrate can benefit us with the increase in efficiency of mass cell culture process for clinical applications.Keywords: acoustic radiation force, cell proliferation, regenerative medicine, resonance vibration, single cell sorter
Procedia PDF Downloads 2638944 Effect of Sanitary-Environmental Conditions of Diabetic Hypertension Incidence of Displaced Persons
Authors: Radmila Maksimovic, Sonja Ketin, Rade Biocanin, Jelena Maksimovic
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The abnormal conditions of life and work genetic factors often play a major role in incidence of diabetes-diabetes, heart disease and vascular disease, jaundice, and post traumatic stress. Trauma and post traumatic stress are most common in the displaced persons,and the focus of this paper is to shed light on this issue in former Yugoslavia, Yugoslavia and now in our country. This is caused by increased beta-cell sensitivity to viruses, the development of autoimmune antibodies against its own pancreascells, degenerative changes in cells that r esult in change of structure and insulin. In this paper, we dealt with traumatic events and long-term psycho social consequences for internally displaced persons, several years after displacement, and found a high level of PTSD symptoms. This stress is present in almost 1/3 of internally displaced persons, and every sixth person is suffering from PTSD in the past. Respondents generally suffer from symptoms of intrusion, but there was a large number of symptoms, avoidance and increased arousal. We also found that gender, age andeducation related to the symptoms. Females, and older respondents and internally displaced persons with lower levels of education how a higher level of PTSD symptoms, especially symptoms of intrusion and increase darousal. It is a highly traumatized sample in which more than 1/2 of respondents experienced more than three traumatic events in life,although the number of traumas experienced before, during and after the conflict varies.We found that during the war, internally displaced persons haveexperienced more traumatic events compared with the periodbefore and after the conflict. Trauma are different in type. No significant correlation between the number of experienced trauma and PTSD, suggesting that it is necessary to further study the structure of past traumas and the intermediary effects of certain risk factors and protective factors.Keywords: living environment, displaced persons, jaundice, diabetes, trauma, diabetic hypertension, post-traumatic stress (PTSD), treatment
Procedia PDF Downloads 3938943 Author Profiling: Prediction of Learners’ Gender on a MOOC Platform Based on Learners’ Comments
Authors: Tahani Aljohani, Jialin Yu, Alexandra. I. Cristea
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The more an educational system knows about a learner, the more personalised interaction it can provide, which leads to better learning. However, asking a learner directly is potentially disruptive, and often ignored by learners. Especially in the booming realm of MOOC Massive Online Learning platforms, only a very low percentage of users disclose demographic information about themselves. Thus, in this paper, we aim to predict learners’ demographic characteristics, by proposing an approach using linguistically motivated Deep Learning Architectures for Learner Profiling, particularly targeting gender prediction on a FutureLearn MOOC platform. Additionally, we tackle here the difficult problem of predicting the gender of learners based on their comments only – which are often available across MOOCs. The most common current approaches to text classification use the Long Short-Term Memory (LSTM) model, considering sentences as sequences. However, human language also has structures. In this research, rather than considering sentences as plain sequences, we hypothesise that higher semantic - and syntactic level sentence processing based on linguistics will render a richer representation. We thus evaluate, the traditional LSTM versus other bleeding edge models, which take into account syntactic structure, such as tree-structured LSTM, Stack-augmented Parser-Interpreter Neural Network (SPINN) and the Structure-Aware Tag Augmented model (SATA). Additionally, we explore using different word-level encoding functions. We have implemented these methods on Our MOOC dataset, which is the most performant one comparing with a public dataset on sentiment analysis that is further used as a cross-examining for the models' results.Keywords: deep learning, data mining, gender predication, MOOCs
Procedia PDF Downloads 1488942 Efficiency of Background Chlorine Residuals against Accidental Microbial Episode in Proto-Type Distribution Network (Rig) Using Central Composite Design (CCD)
Authors: Sajida Rasheed, Imran Hashmi, Luiza Campos, Qizhi Zhou, Kim Keu
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A quadratic model (p ˂ 0.0001) was developed by using central composite design of 50 experimental runs (42 non-center + 8 center points) to assess efficiency of background chlorine residuals in combating accidental microbial episode in a prototype distribution network (DN) (rig). A known amount of background chlorine residuals were maintained in DN and a required number of bacteria, Escherichia coli K-12 strain were introduced by an injection port in the pipe loop system. Samples were taken at various time intervals at different pipe lengths. Spread plate count was performed to count bacterial number. The model developed was significant. With microbial concentration and time (p ˂ 0.0001), pipe length (p ˂ 0.022), background chlorine residuals (p ˂ 0.07) and time^2 (p ˂ 0.09) as significant factors. The ramp function of variables shows that at the microbial count of 10^6, at 0.76 L/min, and pipe length of 133 meters, a background residual chlorine 0.16 mg/L was enough for complete inactivation of microbial episode in approximately 18 minutes.Keywords: central composite design (CCD), distribution network, Escherichia coli, residual chlorine
Procedia PDF Downloads 4628941 Optimization of Cacao Fermentation in Davao Philippines Using Sustainable Method
Authors: Ian Marc G. Cabugsa, Kim Ryan Won, Kareem Mamac, Manuel Dee, Merlita Garcia
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An optimized cacao fermentation technique was developed for the cacao farmers of Davao City Philippines. Cacao samples with weights ranging from 150-250 kilograms were collected from various cacao farms in Davao City and Zamboanga City Philippines. Different fermentation techniques were used starting with design of the sweat box, prefermentation conditionings, number of days for fermentation and number of turns. As the beans are being fermented, its temperature was regularly monitored using a digital thermometer. The resultant cacao beans were assessed using physical and chemical means. For the physical assessment, the bean cut test, bean count tests, and sensory test were used. Quantification of theobromine, caffeine, and antioxidants in the form of equivalent quercetin was used for chemical assessment. Both the theobromine and caffeine were analyzed using HPLC method while the antioxidant was analyzed spectrometrically. To come up with the best fermentation procedure, the different assessment were given priority coefficients wherein the physical tests – taste test, cut, and bean count tests were given priority over the results of the chemical test. The result of the study was an optimized fermentation protocol that is readily adaptable and transferable to any cacao cooperatives or groups in Mindanao or even Philippines as a whole.Keywords: cacao, fermentation, HPLC, optimization, Philippines
Procedia PDF Downloads 4528940 Frequency of Gastrointestinal Manifestations in Systemic Sclerosis and Impact of Rituximab Treatment
Authors: Liudmila Garzanova, Lidia Ananyeva, Olga Koneva, Olga Ovsyannikova, Oxana Desinova, Mayya Starovoytova, Rushana Shayahmetova
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Objectives. Gastrointestinal involvement is one of the most common manifestations of systemic sclerosis (SSc). The aim of our study was to assess the frequency of gastrointestinal manifestations in SSc patients (pts) with interstitial lung disease (ILD) and their changes to rituximab (RTX) therapy. Methods. There were 103 pts with SSc in this study. The mean follow-up period was 12.6±10.7 months. The mean age was 47±12.9 years, females - 87 pts (84%), and the diffuse cutaneous subset of the disease 55 pts (53%). The mean disease duration was 6.2±5.5 years. All pts had ILD and were positive for ANA. 67% of them were positive for anti-topoisomerase-1. All patients received prednisolone at a dose of 11.3±4.5 mg/day, and immunosuppressants at inclusion received 47% of them. Pts received RTX due to the ineffectiveness of previous therapy for ILD. The cumulative mean dose of RTX was 1.7±0.6 grams. 90% of pts received omeprazole at a dose of 20-40 mg/day. Results. At inclusion, dysphagia was observed in 76 pts (74%), early satiety or vomiting in 32 pts (31%), and diarrhea in 20 pts (19%). We didn't observe any changes in gastrointestinal manifestation during RTX therapy. There was a decrease in the number of pts with dysphagia from 76 (74%) to 66 (64%), but it was insignificant. The number of pts with early satiety or vomiting and diarrhea didn't change. Conclusion. In our study, gastrointestinal involvement was observed in most of the pts with SSc-ILD. We didn't find any significant changes in gastrointestinal manifestations during RTX therapy. RXT does not worsen gastrointestinal manifestations in SSc-ILD.Keywords: systemic sclerosis, dysphagia, rituximab, gastrointestinal manifestations
Procedia PDF Downloads 828939 Organising Field Practicum for International Social Work Students through Creative Projects in the Community Sector in Elderly Care: An Evaluation of the Placement Experiences
Authors: Kalpana Goel
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Australian social work schools are finding it difficult to find appropriate placements for the increasing number of international students enrolled in their Master of Social Work qualifying (MSWQ) programs. Anecdotally, it has been noticed that fewer social work students are ready to work with older people whose numbers are rising globally. An innovative and unique placement for international students enrolled in the MSWQ at one Australian university was organised in partnership with a community-based service working with older clients to meet two objectives: increasing the number of suitable placements for international students and preparing social work students to work with older people. Creative activities and projects were designed to provide meaningful engagement and experience in working with older people in the community. Students participated in a number of projects that were matched with their interest and capability in a 500-hour placement. The students were asked to complete an online survey after all work for the placement had been completed. The areas of assessment were: self-perceived change in perception towards age and older people, valued field placement experiences including reflective practice, knowledge and skill development, and constraints and challenges experienced in the placement. Findings revealed students’ increased level of confidence in applying social work theory to practice, developing effective communication and interpersonal skills, and use of innovation and creativity in preparing well-being plans with older adults. Challenges and constraints related to their limited English language ability and lack of cultural knowledge of the host society. It was recognised that extra support for these students and more planning in the beginning phase of placement are vital to placement success. Caution in matching students with clients of similar cultural background must be exercised to ensure that there is equity in task allocation and opportunities for wider experiences.Keywords: field placement, international students, older people, social work
Procedia PDF Downloads 1688938 Unlocking Justice: Exploring the Power and Challenges of DNA Analysis in the Criminal Justice System
Authors: Sandhra M. Pillai
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This article examines the relevance, difficulties, and potential applications of DNA analysis in the criminal justice system. A potent tool for connecting suspects to crime sites, clearing the innocent of wrongdoing, and resolving cold cases, DNA analysis has transformed forensic investigations. The scientific foundations of DNA analysis, including DNA extraction, sequencing, and statistical analysis, are covered in the article. To guarantee accurate and trustworthy findings, it also discusses the significance of quality assurance procedures, chain of custody, and DNA sample storage. DNA analysis has significantly advanced science, but it also brings up substantial moral and legal issues. To safeguard individual rights and uphold public confidence, privacy concerns, possible discrimination, and abuse of DNA information must be properly addressed. The paper also emphasises the effects of the criminal justice system on people and communities while highlighting the necessity of equity, openness, and fair access to DNA testing. The essay describes the obstacles and future directions for DNA analysis. It looks at cutting-edge technology like next-generation sequencing, which promises to make DNA analysis quicker and more affordable. To secure the appropriate and informed use of DNA evidence, it also emphasises the significance of multidisciplinary collaboration among scientists, law enforcement organisations, legal experts, and policymakers. In conclusion, DNA analysis has enormous potential for improving the course of criminal justice. We can exploit the potential of DNA technology while respecting the ideals of justice, fairness, and individual rights by navigating the ethical, legal, and societal issues and encouraging discussion and collaboration.Keywords: DNA analysis, DNA evidence, reliability, validity, legal frame, admissibility, ethical considerations, impact, future direction, challenges
Procedia PDF Downloads 648937 From Text to Data: Sentiment Analysis of Presidential Election Political Forums
Authors: Sergio V Davalos, Alison L. Watkins
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User generated content (UGC) such as website post has data associated with it: time of the post, gender, location, type of device, and number of words. The text entered in user generated content (UGC) can provide a valuable dimension for analysis. In this research, each user post is treated as a collection of terms (words). In addition to the number of words per post, the frequency of each term is determined by post and by the sum of occurrences in all posts. This research focuses on one specific aspect of UGC: sentiment. Sentiment analysis (SA) was applied to the content (user posts) of two sets of political forums related to the US presidential elections for 2012 and 2016. Sentiment analysis results in deriving data from the text. This enables the subsequent application of data analytic methods. The SASA (SAIL/SAI Sentiment Analyzer) model was used for sentiment analysis. The application of SASA resulted with a sentiment score for each post. Based on the sentiment scores for the posts there are significant differences between the content and sentiment of the two sets for the 2012 and 2016 presidential election forums. In the 2012 forums, 38% of the forums started with positive sentiment and 16% with negative sentiment. In the 2016 forums, 29% started with positive sentiment and 15% with negative sentiment. There also were changes in sentiment over time. For both elections as the election got closer, the cumulative sentiment score became negative. The candidate who won each election was in the more posts than the losing candidates. In the case of Trump, there were more negative posts than Clinton’s highest number of posts which were positive. KNIME topic modeling was used to derive topics from the posts. There were also changes in topics and keyword emphasis over time. Initially, the political parties were the most referenced and as the election got closer the emphasis changed to the candidates. The performance of the SASA method proved to predict sentiment better than four other methods in Sentibench. The research resulted in deriving sentiment data from text. In combination with other data, the sentiment data provided insight and discovery about user sentiment in the US presidential elections for 2012 and 2016.Keywords: sentiment analysis, text mining, user generated content, US presidential elections
Procedia PDF Downloads 1928936 Random Subspace Neural Classifier for Meteor Recognition in the Night Sky
Authors: Carlos Vera, Tetyana Baydyk, Ernst Kussul, Graciela Velasco, Miguel Aparicio
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This article describes the Random Subspace Neural Classifier (RSC) for the recognition of meteors in the night sky. We used images of meteors entering the atmosphere at night between 8:00 p.m.-5: 00 a.m. The objective of this project is to classify meteor and star images (with stars as the image background). The monitoring of the sky and the classification of meteors are made for future applications by scientists. The image database was collected from different websites. We worked with RGB-type images with dimensions of 220x220 pixels stored in the BitMap Protocol (BMP) format. Subsequent window scanning and processing were carried out for each image. The scan window where the characteristics were extracted had the size of 20x20 pixels with a scanning step size of 10 pixels. Brightness, contrast and contour orientation histograms were used as inputs for the RSC. The RSC worked with two classes and classified into: 1) with meteors and 2) without meteors. Different tests were carried out by varying the number of training cycles and the number of images for training and recognition. The percentage error for the neural classifier was calculated. The results show a good RSC classifier response with 89% correct recognition. The results of these experiments are presented and discussed.Keywords: contour orientation histogram, meteors, night sky, RSC neural classifier, stars
Procedia PDF Downloads 1398935 Access to Education and Adopted Identity of the Rohingya Amid Government Restrictions in Bangladesh
Authors: Ishrat Zakia Sultana
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The consistent persecution, ethnic cleansing, and genocide against the Rohingya in Burma resulted four major influxes of the Rohingya people to the neighboring country Bangladesh. After the latest influx of October 2016 and August 2017, the total number of Rohingya in Bangladesh stands somewhere between 900,000 to over one million, placing Bangladesh much ahead with the number of refugees compared to Dadaab and Kakuma in Kenya, Bidibidi in Uganda and Zaatari in Jordan. While Bangladesh received recognition and appreciation for receiving a huge number of the Rohingya, one of the fundamental human rights of the Rohingya – education – has never been fulfilled in Bangladesh. The Ministry of Disaster Management and Relief of the government of Bangladesh has been looking after the Rohingya and managing various programs for the Rohingya. On its website, the Ministry claims that it provides the basic supports/services to the Rohingya, including providing education. In practice, however, education for the Rohingya include only the provisions for registered Rohingya refugees – who are a very small number of populations among the entire Rohingya hosted in Bangladesh – and that is only up to grade 7 within the registered camps at Teknaf and Ukhia of Cox’s Bazar district of the country. There is no answer of the question, ‘What’s next’? Although refugees in Canada, Sudan, Turkey and other countries have been allowed to go to mainstream schools, Rohingya refugees in Bangladesh are not allowed to do so legally. Due to the lack of proof of nationality of the Rohingya, the government of Bangladesh imposes restrictions on their access to Bangladeshi schools. However, despite their vulnerability and statelessness, many Rohingyas are desperate to pursue education outside the camps and find their own way not only within Cox’s Bazar but also even in the capital city of the country. But they must hide their refugee identity to accomplish this. My research aims to explore how they manage to get admission amid government restrictions on their access to education in the mainstream institutions in Bangladesh. It will reveal how Rohingya people use adopted identity to get access to education in Bangladesh, and how they apply their own techniques to achieve their goals without having government approved identity. This research examined the strategies the Rohingya applied to manage documents related to their identity to ensure their admission to Bangladeshi education institutions – in schools, colleges, and universities. The research employed a qualitative approach. It used semi structured individual interviews and Focused Group Discussions (FGDs) with 20 male and female Rohingya refugees who are 18 years old and above, and have enrolled in Bangladeshi education institutions with adopted identity. Also I interviewed 5 local community members and policy makers to understand their perceptions and roles in this process. The findings of this research will allow the policy makers to rethink the outcomes of the restrictions on Rohingya’s education in Bangladesh, the ramifications of the denial of Rohingya’s access to education, and initiate policy dialogues on how to allow Rohingya refugees to pursue education in Bangladesh in legal way.Keywords: Rohingya, Refugee, Bangladesh, Education
Procedia PDF Downloads 648934 Image Inpainting Model with Small-Sample Size Based on Generative Adversary Network and Genetic Algorithm
Authors: Jiawen Wang, Qijun Chen
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The performance of most machine-learning methods for image inpainting depends on the quantity and quality of the training samples. However, it is very expensive or even impossible to obtain a great number of training samples in many scenarios. In this paper, an image inpainting model based on a generative adversary network (GAN) is constructed for the cases when the number of training samples is small. Firstly, a feature extraction network (F-net) is incorporated into the GAN network to utilize the available information of the inpainting image. The weighted sum of the extracted feature and the random noise acts as the input to the generative network (G-net). The proposed network can be trained well even when the sample size is very small. Secondly, in the phase of the completion for each damaged image, a genetic algorithm is designed to search an optimized noise input for G-net; based on this optimized input, the parameters of the G-net and F-net are further learned (Once the completion for a certain damaged image ends, the parameters restore to its original values obtained in the training phase) to generate an image patch that not only can fill the missing part of the damaged image smoothly but also has visual semantics.Keywords: image inpainting, generative adversary nets, genetic algorithm, small-sample size
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