Search results for: CO₂ mass transfer
2515 The Healthcare Costs of BMI-Defined Obesity among Adults Who Have Undergone a Medical Procedure in Alberta, Canada
Authors: Sonia Butalia, Huong Luu, Alexis Guigue, Karen J. B. Martins, Khanh Vu, Scott W. Klarenbach
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Obesity is associated with significant personal impacts on health and has a substantial economic burden on payers due to increased healthcare use. A contemporary estimate of the healthcare costs associated with obesity at the population level are lacking. This evidence may provide further rationale for weight management strategies. Methods: Adults who underwent a medical procedure between 2012 and 2019 in Alberta, Canada were categorized into the investigational cohort (had body mass index [BMI]-defined class 2 or 3 obesity based on a procedure-associated code) and the control cohort (did not have the BMI procedure-associated code); those who had bariatric surgery were excluded. Characteristics were presented and healthcare costs ($CDN) determined over a 1-year observation period (2019/2020). Logistic regression and a generalized linear model with log link and gamma distribution were used to assess total healthcare costs (comprised of hospitalizations, emergency department visits, ambulatory care visits, physician visits, and outpatient prescription drugs); potential confounders included age, sex, region of residence, and whether the medical procedure was performed within 6-months before the observation period in the partial adjustment, and also the type of procedure performed, socioeconomic status, Charlson Comorbidity Index (CCI), and seven obesity-related health conditions in the full adjustment. Cost ratios and estimated cost differences with 95% confidence intervals (CI) were reported; incremental cost differences within the adjusted models represent referent cases. Results: The investigational cohort (n=220,190) was older (mean age: 53 standard deviation [SD]±17 vs 50 SD±17 years), had more females (71% vs 57%), lived in rural areas to a greater extent (20% vs 14%), experienced a higher overall burden of disease (CCI: 0.6 SD±1.3 vs 0.3 SD±0.9), and were less socioeconomically well-off (material/social deprivation was lower [14%/14%] in the most well-off quintile vs 20%/19%) compared with controls (n=1,955,548). Unadjusted total healthcare costs were estimated to be 1.77-times (95% CI: 1.76, 1.78) higher in the investigational versus control cohort; each healthcare resource contributed to the higher cost ratio. After adjusting for potential confounders, the total healthcare cost ratio decreased, but remained higher in the investigational versus control cohort (partial adjustment: 1.57 [95% CI: 1.57, 1.58]; full adjustment: 1.21 [95% CI: 1.20, 1.21]); each healthcare resource contributed to the higher cost ratio. Among urban-dwelling 50-year old females who previously had non-operative procedures, no procedures performed within 6-months before the observation period, a social deprivation index score of 3, a CCI score of 0.32, and no history of select obesity-related health conditions, the predicted cost difference between those living with and without obesity was $386 (95% CI: $376, $397). Conclusions: If these findings hold for the Canadian population, one would expect an estimated additional $3.0 billion per year in healthcare costs nationally related to BMI-defined obesity (based on an adult obesity rate of 26% and an estimated annual incremental cost of $386 [21%]); incremental costs are higher when obesity-related health conditions are not adjusted for. Results of this study provide additional rationale for investment in interventions that are effective in preventing and treating obesity and its complications.Keywords: administrative data, body mass index-defined obesity, healthcare cost, real world evidence
Procedia PDF Downloads 1082514 CFD Analysis of Multi-Phase Reacting Transport Phenomena in Discharge Process of Non-Aqueous Lithium-Air Battery
Authors: Jinliang Yuan, Jong-Sung Yu, Bengt Sundén
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A computational fluid dynamics (CFD) model is developed for rechargeable non-aqueous electrolyte lithium-air batteries with a partial opening for oxygen supply to the cathode. Multi-phase transport phenomena occurred in the battery are considered, including dissolved lithium ions and oxygen gas in the liquid electrolyte, solid-phase electron transfer in the porous functional materials and liquid-phase charge transport in the electrolyte. These transport processes are coupled with the electrochemical reactions at the active surfaces, and effects of discharge reaction-generated solid Li2O2 on the transport properties and the electrochemical reaction rate are evaluated and implemented in the model. The predicted results are discussed and analyzed in terms of the spatial and transient distribution of various parameters, such as local oxygen concentration, reaction rate, variable solid Li2O2 volume fraction and porosity, as well as the effective diffusion coefficients. It is found that the effect of the solid Li2O2 product deposited at the solid active surfaces is significant on the transport phenomena and the overall battery performance.Keywords: Computational Fluid Dynamics (CFD), modeling, multi-phase, transport phenomena, lithium-air battery
Procedia PDF Downloads 4512513 Drastic Improvement in Vision Following Surgical Excision of Juvenile Nasopharyngeal Angiofibroma with Compressive Optic Neuropathy
Authors: Sweta Das
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This case report is a 15-year-old male who presented with painless unilateral vision loss from left optic nerve compression due to juvenile nasopharyngeal angiofibroma. JNA is a rare, benign neoplasm that causes intracranial and intraorbital bone destruction and extends aggressively into surrounding soft tissues. It accounts for <1% of all head and neck tumors, is predominantly found in pediatric males and tends to affect indigenous population disproportionately. The most common presenting symptom for JNA is epistaxis and nasal obstruction. However, it can invade orbit, chiasm and pituitary gland, causing loss of vision and field. Visual acuity and function near normalized following surgical excision. Optometry plays an important role in the diagnosis and co-management of JNA with optic nerve compression by closely monitoring afferent optic nerve function and structure, and extraocular motility. Visual function and acuity in patients with short-term compressive neuropathy may drastically improve following surgical resection as this case demonstrates.Keywords: orbital mass, painless monocular vision loss, compressive optic neuropathy, pediatric tumor
Procedia PDF Downloads 602512 Analysis of Translational Ship Oscillations in a Realistic Environment
Authors: Chen Zhang, Bernhard Schwarz-Röhr, Alexander Härting
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To acquire accurate ship motions at the center of gravity, a single low-cost inertial sensor is utilized and applied on board to measure ship oscillating motions. As observations, the three axes accelerations and three axes rotational rates provided by the sensor are used. The mathematical model of processing the observation data includes determination of the distance vector between the sensor and the center of gravity in x, y, and z directions. After setting up the transfer matrix from sensor’s own coordinate system to the ship’s body frame, an extended Kalman filter is applied to deal with nonlinearities between the ship motion in the body frame and the observation information in the sensor’s frame. As a side effect, the method eliminates sensor noise and other unwanted errors. Results are not only roll and pitch, but also linear motions, in particular heave and surge at the center of gravity. For testing, we resort to measurements recorded on a small vessel in a well-defined sea state. With response amplitude operators computed numerically by a commercial software (Seaway), motion characteristics are estimated. These agree well with the measurements after processing with the suggested method.Keywords: extended Kalman filter, nonlinear estimation, sea trial, ship motion estimation
Procedia PDF Downloads 5232511 Electron Impact Ionization Cross-Sections for e-C₅H₅N₅ Scattering
Authors: Manoj Kumar
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Ionization cross sections of molecules due to electron impact play an important role in chemical processes in various branches of applied physics, such as radiation chemistry, gas discharges, plasmas etching in semiconductors, planetary upper atmospheric physics, mass spectrometry, etc. In the present work, we have calculated the total ionization cross sections for Adenine (C₅H₅N₅), a biologically important molecule, by electron impact in the incident electron energy range from ionization threshold to 2 keV employing a well-known Jain-Khare semiempirical formulation based on Bethe and Möllor cross sections. In the non-availability of the experimental results, the present results are in good agreement qualitatively as well as quantitatively with available theoretical results. The present results drive our confidence for further investigation of complex bio-molecule with better accuracy. Notwithstanding, the present method can deduce reliable cross-sectional data for complex targets with adequate accuracy and may facilitate the acclimatization of calculated cross-sections into atomic molecular cross-section data sets for modeling codes and other applications.Keywords: electron impact ionization cross-sections, oscillator strength, jain-khare semiempirical approach
Procedia PDF Downloads 1112510 d-Block Metal Nanoparticles Confined in Triphenylphosphine Oxide Functionalized Core-Crosslinked Micelles for the Application in Biphasic Hydrogenation
Authors: C. Joseph Abou-Fayssal, K. Philippot, R. Poli, E. Manoury, A. Riisager
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The use of soluble polymer-supported metal nanoparticles (MNPs) has received significant attention for the ease of catalyst recovery and recycling. Of particular interest are MNPs that are supported on polymers that are either soluble or form stable colloidal dispersion in water, as this allows to combine of the advantages of the aqueous biphasic protocol with the catalytical performances of MNPs. The objective is to achieve good confinement of the catalyst in the nanoreactor cores and, thus, a better catalyst recovery in order to overcome the previously witnessed MNP extraction. Inspired by previous results, we are interested in the design of polymeric nanoreactors functionalized with ligands able to solidly anchor metallic nanoparticles in order to control the activity and selectivity of the developed nanocatalysts. The nanoreactors are core-crosslinked micelles (CCM) synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Varying the nature of the core-linked functionalities allows us to get differently stabilized metal nanoparticles and thus compare their performance in the catalyzed aqueous biphasic hydrogenation of model substrates. Particular attention is given to catalyst recyclability.Keywords: biphasic catalysis, metal nanoparticles, polymeric nanoreactors, catalyst recovery, RAFT polymerization
Procedia PDF Downloads 1012509 The Politics of Identity and Retributive Genocidal Massacre against Chena Amhara under International Humanitarian Law
Authors: Gashaw Sisay Zenebe
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Northern-Ethiopian conflict that broke out on 04 November 2020 between the central government and TPLF caused destruction beyond imagination in all aspects; millions of people have been killed, including civilians, mainly women, and children. Civilians have been indiscriminately attacked simply because of their ethnic or religious identity. Warrying parties committed serious crimes of international concern opposite to International Humanitarian Law (IHL). A House of People Representatives (HPR) declared that the terrorist Tigrean Defense Force (TDF), encompassing all segments of its people, waged war against North Gondar through human flooding. On Aug 30, 2021, after midnight, TDF launched a surprise attack against Chena People who had been drunk and deep slept due to the annual festivity. Unlike the lowlands, however, ENDF conjoined the local people to fight TDF in these Highland areas. This research examines identity politics and the consequential genocidal massacre of Chena, including its human and physical destructions that occurred as a result of the armed conflict. As such, the study could benefit international entities by helping them develop a better understanding of what happened in Chena and trigger interest in engaging in ensuring the accountability and enforcement of IHL in the future. Preserving fresh evidence will also serve as a starting point on the road to achieving justice either nationally or internationally. To study the Chena case evaluated against IHL rules, a combination of qualitative and doctrinal research methodology has been employed. The study basically follows a unique sampling case study which has used primary data tools such as observation, interview, key-informant interview, FGD, and battle-field notes. To supplement, however, secondary sources, including books, journal articles, domestic laws, international conventions, reports, and media broadcasts, were used to give meaning to what happened on the ground in light of international law. The study proved that the war was taking place to separate Tigray from Ethiopia. While undertaking military operations to achieve this goal, mass killings, genocidal acts, and war crimes were committed over Chena and approximate sites in the Dabat district of North Gondar. Thus, hundreds of people lost their lives to the brutalities of mass killings, hundreds of people were subjected to a forcible disappearance, and tens of thousands of people were forced into displacement. Furthermore, harsh beatings, forced labor, slavery, torture, rape, and gang rape have been reported, and generally, people are subjected to pass cruel, inhuman, and degrading treatment and punishment. Also, what is so unique is that animals were indiscriminately killed completely, making the environment unsafe for human survival because of pollution and bad smells and the consequent diseases such as Cholera, Flu, and Diarrhea. In addition to TDF, ENDF’s shelling has caused destruction to farmers’ houses & claimed lives. According to humanitarian principles, acts that can establish MACs and war crimes were perpetrated. Generally, the war in this direction has shown an absolute disrespect for international law norms.Keywords: genocide, war crimes, Tigray Defense Force, Chena, IHL
Procedia PDF Downloads 722508 A Comprehensive Approach to Create ‘Livable Streets’ in the Mixed Land Use of Urban Neighborhoods: A Case Study of Bangalore Street
Authors: K. C. Tanuja, Mamatha P. Raj
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"People have always lived on streets. They have been the places where children first learned about the world, where neighbours met, the social centres of towns and cities, the rallying points for revolts, the scenes of repression. The street has always been the scene of this conflict, between living and access, between resident and traveller, between street life and the threat of death.” Livable Streets by Donald Appleyard. Urbanisation is happening rapidly all over the world. As population increasing in the urban settlements, its required to provide quality of life to all the inhabitants who live in. Urban design is a place making strategic planning. Urban design principles promote visualising any place environmentally, socially and economically viable. Urban design strategies include building mass, transit development, economic viability and sustenance and social aspects. Cities are wonderful inventions of diversity- People, things, activities, ideas and ideologies. Cities should be smarter and adjustable to present technology and intelligent system. Streets represent the community in terms of social and physical aspects. Streets are an urban form that responds to many issues and are central to urban life. Streets are for livability, safety, mobility, place of interest, economic opportunity, balancing the ecology and for mass transit. Urban streets are places where people walk, shop, meet and engage in different types of social and recreational activities which make urban community enjoyable. Streets knit the urban fabric of activities. Urban streets become livable with the introduction of social network enhancing the pedestrian character by providing good design features which in turn should achieve the minimal impact of motor vehicle use on pedestrians. Livable streets are the spatial definition to the public right of way on urban streets. Streets in India have traditionally been the public spaces where social life happened or created from ages. Streets constitute the urban public realm where people congregate, celebrate and interact. Streets are public places that can promote social interaction, active living and community identity. Streets as potential contributors to a better living environment, knitting together the urban fabric of people and places that make up a community. Livable streets or complete streets are making our streets as social places, roadways and sidewalks accessible, safe, efficient and useable for all people. The purpose of this paper is to understand the concept of livable street and parameters of livability on urban streets. Streets to be designed as the pedestrians are the main users and create spaces and furniture for social interaction which serves for the needs of the people of all ages and abilities. The problems of streets like congestion due to width of the street, traffic movement and adjacent land use and type of movement need to be redesigned and improve conditions defining the clear movement path for vehicles and pedestrians. Well-designed spatial qualities of street enhances the street environment, livability and then achieves quality of life to the pedestrians. A methodology been derived to arrive at the typologies in street design after analysis of existing situation and comparing with livable standards. It was Donald Appleyard‟s Livable Streets laid out the social effects on streets creating the social network to achieve Livable Streets.Keywords: livable streets, social interaction, pedestrian use, urban design
Procedia PDF Downloads 1512507 Effect of Milling Parameters on the Characteristics of Nanocrystalline TiAl Alloys Synthesized by Mechanical Alloying
Authors: Jinan B. Al-Dabbagh, Rozman Mohd Tahar, Mahadzir Ishak
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TiAl alloy nano-powder was successfully produced by a mechanical alloying (MA) technique in a planetary ball mill. The influence of milling parameters, such as the milling duration, rotation speed, and balls-to-powder mass ratio, on the characteristics of the Ti50%Al powder, including the microstructure, crystallite size refinement, and phase formation, were investigated. It was found that MA of elemental Ti and Al powders promotes the formation of TiAl alloys, as Ti (Al) solid solution was formed after 5h of milling. Milling without the addition of process control agents led to a dramatic decrease in the crystallite size to 17.8 nm after 2h of milling. Higher rotation energy and a higher ball-to-powder weight ratio also accelerated the reduction in crystallite size. Subsequent heating up to 850°C resulted in the formation of a new intermetallic phase with a dominant TiAl3 phase plus minor γ-TiAl or α2-Ti3Al phase or both. A longer milling duration also exhibited a better effect on the micro-hardness of Ti50%Al powders.Keywords: TiAl alloys, nanocrystalline materials, mechanical alloying, materials science
Procedia PDF Downloads 3582506 Numerical Study of Rayleight Number and Eccentricity Effect on Free Convection Fluid Flow and Heat Transfer of Annulus
Authors: Ali Reza Tahavvor‚ Saeed Hosseini, Behnam Amiri
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Concentric and eccentric annulus is used frequently in technical and industrial applications such as nuclear reactors, thermal storage system and etc. In this paper, computational fluid dynamics (CFD) is used to investigate two dimensional free convection of laminar flow in annulus with isotherm cylinders surface and cooler inner surface. Problem studied in thirty different cases. Due to natural convection continuity and momentum equations are coupled and must be solved simultaneously. Finite volume method is used for solving governing equations. The purpose was to obtain the eccentricity effect on Nusselt number in different Rayleight numbers, so streamlines and temperature fields must be determined. Results shown that the highest Nusselt number values occurs in degree of eccentricity equal to 0.5 upward for inner cylinder and degree of eccentricity equal to 0.3 upward for outer cylinder. Side eccentricity reduces the outer cylinder Nusselt number but increases inner cylinder Nusselt number. The trend in variation of Nusselt number with respect to eccentricity remain similar in different Rayleight numbers. Correlations are included to calculate the Nusselt number of the cylinders.Keywords: natural convection, concentric, eccentric, Nusselt number, annulus
Procedia PDF Downloads 3702505 Bio-polymer Materials for Sustainable Consumer and Medical Applications
Authors: Sonny Yip Hong Choy
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With the ubiquity of 3D printing technology in the last decade, a wide array of material choices are available for Fused Deposition Modelling (FDM) 3D printing technology. Exploration into creating printable bio-polymers has also seen progress recently in attempts to further the sustainability agenda and circular economy. By tackling waste and pollution via recycling and reusing, food by-products resulting from mass food production may see opportunities for renewed value and alternate applications through 3D printing. To date, many pure polymers, blends, as well as composites have been developed specifically for FDM printing contexts to heighten the physical performance of final printed products. This review article covers general information on various FDM printed polymers and composites while exploring experiments designed to create printable biopolymers made from reused food by-products. The biopolymer-based composites preparation is described in detail, while their advantages and disadvantages are also discussed. In addition, this article shares knowledge and highlights experimentation that aims to achieve acceptable 3D-printed biopolymer composite properties that may address the functional requirements of different application contexts. Furthermore, the article describes a brief overview of the potential applications of such bio-polymers and the future scope in this field.Keywords: food by-products, bio-polymers, FDM, 3d printing
Procedia PDF Downloads 822504 Statistical Analysis of the Impact of Maritime Transport Gross Domestic Product (GDP) on Nigeria’s Economy
Authors: Kehinde Peter Oyeduntan, Kayode Oshinubi
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Nigeria is referred as the ‘Giant of Africa’ due to high population, land mass and large economy. However, it still trails far behind many smaller economies in the continent in terms of maritime operations. As we have seen that the maritime industry is the spark plug for national growth, because it houses the most crucial infrastructure that generates wealth for a nation, it is worrisome that a nation with six seaports lag in maritime activities. In this research, we have studied how the Gross Domestic Product (GDP) of the maritime transport influences the Nigerian economy. To do this, we applied Simple Linear Regression (SLR), Support Vector Machine (SVM), Polynomial Regression Model (PRM), Generalized Additive Model (GAM) and Generalized Linear Mixed Model (GLMM) to model the relationship between the nation’s Total GDP (TGDP) and the Maritime Transport GDP (MGDP) using a time series data of 20 years. The result showed that the MGDP is statistically significant to the Nigerian economy. Amongst the statistical tool applied, the PRM of order 4 describes the relationship better when compared to other methods. The recommendations presented in this study will guide policy makers and help improve the economy of Nigeria in terms of its GDP.Keywords: maritime transport, economy, GDP, regression, port
Procedia PDF Downloads 1542503 Carbon Coated Yarn Supercapacitors: Parametric Study of Performance Output
Authors: Imtiaz Ahmed Khan, Sabu John, Sania Waqar, Lijing Wang, Mac Fergusson, Ilija Najdovski
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Evolution of textiles, from its orthodox to more interactive role has stirred the researchers to uncover its application in numerous arenas. The idea of using textile based materials for wearable energy harvesting and storage devices have gained immense popularity. This is mainly due to textile comfort and flexibility features. In this work, nano-carbonous materials were infused on cellulosic fibers using caustic soda treatment. This paper presents the complete procedure of yarn supercapacitors fabrication process through dip coating technique and its characterization method. The main objective is to study, the effect of varying caustic soda concentration on mass loading of activated carbon on yarns and the related capacitance output of the designed yarn supercapacitor. Polyvinyl alcohol and Phosphoric acid were used as electrolyte in a two-electrode cell assembly to measure device electrochemical performance. The results show a promising increase in capacitance value using this technique.Keywords: yarn supercapacitors, activated carbon, dip coating, caustic soda, electrolyte, electrochemical characterization
Procedia PDF Downloads 4632502 Identification of Switched Reluctance Motor Parameters Using Exponential Swept-Sine Signal
Authors: Abdelmalek Ouannou, Adil Brouri, Laila Kadi, Tarik
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Switched reluctance motor (SRM) has a major interest in a large domain as in electric vehicle driving because of its wide range of speed operation, high performances, low cost, and robustness to run under degraded conditions. The purpose of the paper is to develop a new analytical approach for modeling SRM parameters. Then, an identification scheme is proposed to obtain the SRM parameters. Since the SRM is featured by a highly nonlinear behavior, modeling these devices is difficult. Then, it is convenient to develop an accurate model describing the SRM. Furthermore, it is always operated in the magnetically saturated mode to maximize the energy transfer. Accordingly, it is shown that the SRM can be accurately described by a generalized polynomial Hammerstein model, i.e., the parallel connection of several Hammerstein models having polynomial nonlinearity. Presently an analytical identification method is developed using a chirp excitation signal. Afterward, the parameters of the obtained model have been determined using Finite Element Method analysis. Finally, in order to show the effectiveness of the proposed method, a comparison between the true and estimate models has been performed. The obtained results show that the output responses are very close.Keywords: switched reluctance motor, swept-sine signal, generalized Hammerstein model, nonlinear system
Procedia PDF Downloads 2372501 Effects of Repeated High Loadings on the Performance of Adhesively-Bonded Single Lap Joints
Authors: Orkun Yavuz, Ferhat Kadioğlu, M. Emin Ercan
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This study aims to investigate the effects of repeated high loadings on the performance of adhesively-bonded Single Lap Joints (SLJs) by employing both experimental and numerical approaches. A projectile with a mass of 1.25 gr and density of 11.3 gr/cm3 was fired at the joints with a velocity of about 280 m/s using a specially designed experimental set-up, and the impact was recorded via a high-speed camera. The SLJs were manufactured from 6061 aluminum adherend (AA6061) material and an adhesive film. The joints, which have an adherend thickness of 4 mm and overlap length of 15 mm, were subjected to up to 3 shots for the ballistic test, followed by quasi-static tensile testing. The impacted joints, then, were compared to the non-impacted and one-shot impacted ones, which was a subject of investigation carried out before. It was found that while the joints subjected to 2 shots mechanically deteriorated, those subjected to 3 shots experienced a complete failure at the end of the experiment. A numerical study was also conducted using an ABAQUS package program. While the adherends were modelled using the Johnson-Cook deformation parameters, an elastoplastic behavior of the adhesive was used as input data in the analyses. It seems the experimental results confirm the numerical ones.Keywords: ballistic tests, adhesive joints, numerical analysis, SLJ
Procedia PDF Downloads 642500 [Keynote Speaker]: Some Similarity Considerations for Design of Experiments for Hybrid Buoyant Aerial Vehicle
Authors: A. U. Haque, W. Asrar, A. A Omar, E. Sulaeman, J. S. M. Ali
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Buoyancy force applied on deformable symmetric bodies can be estimated by using Archimedes Principle. Such bodies like ellipsoidal bodies have high volume to surface ratio and are isometrically scaled for mass, length, area and volume to follow square cube law. For scaling up such bodies, it is worthwhile to find out the scaling relationship between the other physical quantities that represent thermodynamic, structural and inertial response etc. So, dimensionless similarities to find an allometric scale can be developed by using Bukingham π theorem which utilizes physical dimensions of important parameters. Base on this fact, physical dependencies of buoyancy system are reviewed to find the set of physical variables for deformable bodies of revolution filled with expandable gas like helium. Due to change in atmospheric conditions, this gas changes its volume and this change can effect the stability of elongated bodies on the ground as well as in te air. Special emphasis was given on the existing similarity parameters which can be used in the design of experiments of such bodies whose shape is affected by the external force like a drag, surface tension and kinetic loads acting on the surface. All these similarity criteria are based on non-dimensionalization, which also needs to be consider for scaling up such bodies.Keywords: Bukhigham pi theorem, similitude, scaling, buoyancy
Procedia PDF Downloads 3762499 Optimisation of Nitrogen as a Protective Gas via the Alternating Shielding Gas Technique in the Gas Metal Arc Welding Process
Authors: M. P. E. E Silva, A. M. Galloway, A. I. Toumpis
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An increasing concern exists in the welding industry in terms of faster joining processes. Methods such as the alternation between shielding gases such Ar, CO₂ and He have been able to provide improved penetration of the joint, reduced heat transfer to the workpiece, and increased travel speeds of the welding torch. Nitrogen as a shielding gas is not desirable due to its reactive behavior within the arc plasma, being absorbed by the molten pool during the welding process. Below certain amounts, nitrogen is not harmful. However, the nitrogen threshold is reduced during the solidification of the joint, and if its subsequent desorption is not completed on time, gas entrapment and blowhole formation may occur. The present study expanded the use of the alternating shielding gas method in the gas metal arc welding (GMAW) process by alternately supplying Ar/5%N₂ and He. Improvements were introduced in terms of joint strength and grain refinement. Microstructural characterization findings showed porosity-free welds with reduced inclusion formation while mechanical tests such as tensile and bend tests confirmed the reinforcement of the joint by the addition of nitrogen. Additionally, significant reductions of the final distortion of the workpiece were found after the welding procedure as well as decreased heat affected zones and temperatures of the weld.Keywords: alternating shielding gas method, GMAW, grain refinement, nitrogen, porosity, mechanical testing
Procedia PDF Downloads 1102498 Body Image Dissatifaction with and Personal Behavioral Control in Obese Patients Who are Attending to Treatment
Authors: Mariela Gonzalez, Zoraide Lugli, Eleonora Vivas, Rosana Guzmán
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The objective was to determine the predictive capacity of self-efficacy perceived for weight control, locus of weight control and skills of weight self-management in the dissatisfaction of the body image in obese people who attend treatment. Sectional study conducted in the city of Maracay, Venezuela, with 243 obese who attend to treatment, 173 of the feminine gender and 70 of the male, with ages ranging between 18 and 57 years old. The sample body mass index ranged between 29.39 and 44.14. The following instruments were used: The Body Shape Questionnaire (BSQ), the inventory of body weight self-regulation, The Inventory of self-efficacy in the regulation of body weight and the Inventory of the Locus of weight control. Calculating the descriptive statistics and of central tendency, coefficients of correlation and multiple regression; it was found that a low ‘perceived Self-efficacy in the weight control’ and a high ‘Locus of external control’, predict the dissatisfaction with body image in obese who attend treatment. The findings are a first approximation to give an account of the importance of the personal control variables in the study of the psychological grief on the overweight individual.Keywords: dissatisfaction with body image, obese people, personal control, psychological variables
Procedia PDF Downloads 4332497 Performance of Derna Steam Power Plant at Varying Super-Heater Operating Conditions Based on Exergy
Authors: Idris Elfeituri
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In the current study, energy and exergy analysis of a 65 MW steam power plant was carried out. This study investigated the effect of variations of overall conductance of the super heater on the performance of an existing steam power plant located in Derna, Libya. The performance of the power plant was estimated by a mathematical modelling which considers the off-design operating conditions of each component. A fully interactive computer program based on the mass, energy and exergy balance equations has been developed. The maximum exergy destruction has been found in the steam generation unit. A 50% reduction in the design value of overall conductance of the super heater has been achieved, which accordingly decreases the amount of the net electrical power that would be generated by at least 13 MW, as well as the overall plant exergy efficiency by at least 6.4%, and at the same time that would cause an increase of the total exergy destruction by at least 14 MW. The achieved results showed that the super heater design and operating conditions play an important role on the thermodynamics performance and the fuel utilization of the power plant. Moreover, these considerations are very useful in the process of the decision that should be taken at the occasions of deciding whether to replace or renovate the super heater of the power plant.Keywords: Exergy, Super-heater, Fouling; Steam power plant; Off-design., Fouling;, Super-heater, Steam power plant
Procedia PDF Downloads 3332496 A Case of Apocrine Sweat Gland Adenocarcinoma in a Tabby Cat
Authors: Funda Terzi, Elif Dogan, Ayse B. Kapcak
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In this report, clinical, radiological, macroscopic, and histopathological findings of apocrine sweat gland adenocarcinoma are presented in a 13-year-old male tabby cat. In clinical examination, soft tissue masses were detected in the caudal abdomen and left tuber coxae. On radiological examination, subcutaneous masses with soft tissue contrast appearance were detected, and the masses were surgically removed under general anesthesia. The sizes of the masses were approximately 2x2x3 cm in the caudal abdomen and approximately 1x1x2 cm in the tuber coxae region. The cross-section of the mass was whitish-yellow in color. After the masses were fixed in 10% formaldehyde solution, a routine histopathology procedure was applied. In histopathological examination, apocrine sweat glands in a cystic structure and extensions from the center of the cyst to the lumen were determined, and anisonucleosis, anisocytosis, and anaplastic cells with giant nuclei were observed in the epithelial cells of the gland facing the lumen. A diagnosis of papillary-cystic type apocrine sweat gland adenocarcinoma was made with these findings.Keywords: apocrine sweat gland, carcinoma, cat, histopathology
Procedia PDF Downloads 1762495 Synthesis, Characterization, Computational Study, Antimicrobial Evaluation, in Vivo Toxicity Study of Manganese (II) and Copper (II) Complexes with Derivative Sulfa-drug
Authors: Afaf Bouchoucha, Karima Si Larbi, Mohamed Amine Bourouaia, Salah.Boulanouar, Safia.Djabbar
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The synthesis, characterization and comparative biological study of manganese (II) and copper (II) complexes with an heterocyclic ligand used in pharmaceutical field (Scheme 1), were reported. Two kinds of complexes were obtained with derivative sulfonamide, [M (L)₂ (H₂O)₂].H₂O and [M (L)₂ (Cl)₂]3H₂O. These complexes have been prepared and characterized by elemental analysis, FAB mass, ESR magnetic measurements, FTIR, UV-Visible spectra and conductivity. Their stability constants have been determined by potentiometric methods in a water-ethanol (90:10 v/v) mixture at a 0.2 mol l-1 ionic strength (NaCl) and at 25.0 ± 0.1 ºC using Sirko program. DFT calculations were done using B3LYP/6-31G(d) and B3LYP/LanL2DZ. The antimicrobial activity of ligand and complexes against the species Escherichia coli, P. aeruginosa, Klebsiella pneumoniae, S. aureus, Bacillus subtilisan, Candida albicans, Candida tropicalis, Saccharomyces, Aspergillus fumigatus and Aspergillus terreus has been carried out and compared using agar-diffusion method. Also, the toxicity study was evaluated on synchesis complexes using Mice of NMRI strain.Keywords: hetterocyclic ligand, complex, stability constant, antimicrobial activity, DFT, acute and genotoxicity study
Procedia PDF Downloads 1212494 Comparative Study of Concrete Filled Steel I-Girder Bridge with Conventional Type of Bridge
Authors: Waheed Ahmad Safi, Shunichi Nakamura, Abdul Habib Ghaforzai
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Steel and concrete composite bridge with concrete filled steel I-girder (CFIG) was proposed and FEM and laboratory tests were conducted to analysis bending and shear behavior. The proposed form of structural steel I-section is mainly used at the intermediate support zone by placing infilled concrete into the top and bottom flanges of steel I-section to resist negative bending moment. The bending and shear tests were carried out to find out the significance of CFIG section. The result for test showing that the bending and shear capacity of proposed CFIG is at least 3 times and 2 times greater than conventional steel I-section (IG) respectively. Finite element study was also carried out to ensure the result for laboratory tests due to bending and shear behavior and load transfer behavior of proposed structural form. Finite element result result agreed the test result. A design example was carried out for a four-span continuous highway bridge and design method was established.Keywords: bending strength, concrete filled steel I-girder, steel I-girder, FEM, limit states design and shear strength
Procedia PDF Downloads 1312493 Finch-Skea Stellar Structures in F(R, ϕ, X) Theory of Gravity Using Bardeen Geometry
Authors: Aqsa Asharaf
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The current study aims to examine the physical characteristics of charge compact spheres employing anisotropic fluid under f(R, ϕ, X) modified gravity approach, exploring how this theoretical context influences their attributes and behavior. To accomplish our goal, we adopt the Spherically Symmetric (SS) space-time and, additionally, employ a specific Adler-based mode for the metric potential (gtt), which yields a broader class of solutions, Then, by making use of the Karmarkar condition, we successfully derive the other metric potential. A primary component of our current analysis is utilizing the Bardeen geometry as extrinsic space-time to determine the constant parameters of intrinsic space-time. Further, to validate the existence of Bardeen stellar spheres, we debate the behavior of physical properties and parameters such as components of pressure, energy density, anisotropy, parameters of EoS, stability and dynamical equilibrium, energy bounds, mass function, adiabatic index, compactness factor, and surface redshift. Conclusively, all the obtained results show that the system under consideration is physically stable, free from singularity, and viable models.Keywords: cosmology, GR, Bardeen BH, modified gravities
Procedia PDF Downloads 312492 TiO2 Nanowires as Efficient Heterogeneous Photocatalysts for Waste-Water Treatment
Authors: Gul Afreen, Sreedevi Upadhyayula, Mahendra K. Sunkara
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One-dimensional (1D) nanostructures like nanowires, nanotubes, and nanorods find variety of practical application owing to their unique physico-chemical properties. In this work, TiO2 nanowires were synthesized by direct oxidation of titanium particles in a unique microwave plasma jet reactor. The prepared TiO2 nanowires manifested the flexible features, and were characterized by using X-ray diffraction, Brunauer-Emmett-Teller (BET) surface area analyzer, UV-Visible and FTIR spectrophotometers, Scanning electron microscope, and Transmission electron microscope. Further, the photodegradation efficiency of these nanowires were tested against toxic organic dye like methylene blue (MB) and the results were compared with the commercial TiO2. It was found that TiO2 nanowires exhibited superior photocatalytic performance (89%) as compared to commercial TiO2 (75%) after 60 min of reaction. This is attributed to the lower recombination rate and increased interfacial charge transfer in TiO2 nanowire. Pseudo-first order kinetic modelling performed with the experimental results revealed that the rate constant of photodegradation in case of TiO2 nanowire was 1.3 times higher than that of commercial TiO2. Superoxide radical (O2˙−) was found to be the major contributor in the photodegradation mechanism. Based on the trapping experiments, a plausible mechanism of the photocatalytic reaction is discussed.Keywords: heterogeneous catalysis, photodegradation, reactive oxygen species, TiO₂ nanowires
Procedia PDF Downloads 1442491 A Cohort Study of Early Cardiologist Consultation by Telemedicine on the Critical Non-STEMI Inpatients
Authors: Wisit Wichitkosoom
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Objectives: To find out the more effect of early cardiologist consultation using a simple technology on the diagnosis and early proper management of patients with Non-STEMI at emergency department of district hospitals without cardiologist on site before transferred. Methods: A cohort study was performed in Udonthani general hospital at Udonthani province. From 1 October 2012–30 September 2013 with 892 patients diagnosed with Non-STEMI. All patients mean aged 46.8 years of age who had been transferred because of Non-STEMI diagnosed, over a 12 week period of studied. Patients whose transferred, in addition to receiving proper care, were offered a cardiologist consultation with average time to Udonthani hospital 1.5 hour. The main outcome measure was length of hospital stay, mortality at 3 months, inpatient investigation, and transfer rate to the higher facilitated hospital were also studied. Results: Hospital stay was significantly shorter for those didn’t consult cardiologist (hazard ratio 1.19; approximate 95% CI 1.001 to 1.251; p = 0.039). The 136 cases were transferred to higher facilitated hospital. No statistically significant in overall mortality between the groups (p=0.068). Conclusions: Early cardiologist consultant can reduce length of hospital stay for patients with cardiovascular conditions outside of cardiac center. The new basic technology can apply for the safety patient.Keywords: critical, telemedicine, safety, non STEMI
Procedia PDF Downloads 4182490 Exfoliation of Functionalized High Structural Integrity Graphene Nanoplatelets at Extremely Low Temperature
Authors: Mohannad N. H. Al-Malichi
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Because of its exceptional properties, graphene has become the most promising nanomaterial for the development of a new generation of advanced materials from battery electrodes to structural composites. However, current methods to meet requirements for the mass production of high-quality graphene are limited by harsh oxidation, high temperatures, and tedious processing steps. To extend the scope of the bulk production of graphene, herein, a facile, reproducible and cost-effective approach has been developed. This involved heating a specific mixture of chemical materials at an extremely low temperature (70 C) for a short period (7 minutes) to exfoliate functionalized graphene platelets with high structural integrity. The obtained graphene platelets have an average thickness of 3.86±0.71 nm and a lateral size less than ~2 µm with a low defect intensity ID/IG ~0.06. The thin film (~2 µm thick) exhibited a low surface resistance of ~0.63 Ω/sq⁻¹, confirming its high electrical conductivity. Additionally, these nanoplatelets were decorated with polar functional groups (epoxy and carboxyl groups), thus have the potential to toughen and provide multifunctional polymer nanocomposites. Moreover, such a simple method can be further exploited for the novel exfoliation of other layered two-dimensional materials such as MXenes.Keywords: functionalized graphene nanoplatelets, high structural integrity graphene, low temperature exfoliation of graphene, functional graphene platelets
Procedia PDF Downloads 1202489 A Hybrid Combustion Chamber Design for Diesel Engines
Authors: R. Gopakumar, G. Nagarajan
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Both DI and IDI systems possess inherent advantages as well as disadvantages. The objective of the present work is to obtain maximum advantages of both systems by implementing a hybrid design. A hybrid combustion chamber design consists of two combustion chambers viz., the main combustion chamber and an auxiliary combustion chamber. A fuel injector supplies major quantity of fuel to the auxiliary chamber. Due to the increased swirl motion in auxiliary chamber, mixing becomes more efficient which contributes to reduction in soot/particulate emissions. Also, by increasing the fuel injection pressure, NOx emissions can be reduced. The main objective of the hybrid combustion chamber design is to merge the positive features of both DI and IDI combustion chamber designs, which provides increased swirl motion and improved thermal efficiency. Due to the efficient utilization of fuel, low specific fuel consumption can be ensured. This system also aids in increasing the power output for same compression ratio and injection timing as compared with the conventional combustion chamber designs. The present system also reduces heat transfer and fluid dynamic losses which are encountered in IDI diesel engines. Since the losses are reduced, overall efficiency of the engine increases. It also minimizes the combustion noise and NOx emissions in conventional DI diesel engines.Keywords: DI, IDI, hybrid combustion, diesel engines
Procedia PDF Downloads 5332488 Coupling Time-Domain Analysis for Dynamic Positioning during S-Lay Installation
Authors: Sun Li-Ping, Zhu Jian-Xun, Liu Sheng-Nan
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In order to study the performance of dynamic positioning system during S-lay operations, dynamic positioning system is simulated with the hull-stinger-pipe coupling effect. The roller of stinger is simulated by the generalized elastic contact theory. The stinger is composed of Morrison members. Force on pipe is calculated by lumped mass method. Time domain of fully coupled barge model is analyzed combining with PID controller, Kalman filter and allocation of thrust using Sequential Quadratic Programming method. It is also analyzed that the effect of hull wave frequency motion on pipe-stinger coupling force and dynamic positioning system. Besides, it is studied that how S-lay operations affect the dynamic positioning accuracy. The simulation results are proved to be available by checking pipe stress with API criterion. The effect of heave and yaw motion cannot be ignored on hull-stinger-pipe coupling force and dynamic positioning system. It is important to decrease the barge’s pitch motion and lay pipe in head sea in order to improve safety of the S-lay installation and dynamic positioning.Keywords: S-lay operation, dynamic positioning, coupling motion, time domain, allocation of thrust
Procedia PDF Downloads 4652487 Coefficient of Performance (COP) Optimization of an R134a Cross Vane Expander Compressor Refrigeration System
Authors: Y. D. Lim, K. S. Yap, K. T. Ooi
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Cross Vane Expander Compressor (CVEC) is a newly invented expander-compressor combined unit, where it is introduced to replace the compressor and the expansion valve in traditional refrigeration system. The mathematical model of CVEC has been developed to examine its performance, and it was found that the energy consumption of a conventional refrigeration system was reduced by as much as 18%. It is believed that energy consumption can be further reduced by optimizing the device. In this study, the coefficient of performance (COP) of CVEC has been optimized under predetermined operational parameters and constrained main design parameters. Several main design parameters of CVEC were selected to be the variables, and the optimization was done with theoretical model in a simulation program. The theoretical model consists of geometrical model, dynamic model, heat transfer model and valve dynamics model. Complex optimization method, which is a constrained, direct search and multi-variables method was used in the study. As a result, the optimization study suggested that with an appropriate combination of design parameters, a 58% COP improvement in CVEC R134a refrigeration system is possible.Keywords: COP, cross vane expander-compressor, CVEC, design, simulation, refrigeration system, air-conditioning, R134a, multi variables
Procedia PDF Downloads 3342486 The Use of Facebook as a Social Media by Political Parties in the June 7 Election in Konya
Authors: Yasemin Gülşen Yılmaz, Süleyman Hakan Yılmaz, Muhammet Erbay
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Social media is among the most important means of communication. Social media offers individuals and groups with an opportunity for participatory socialization over the internet, which is free of any time and place restrictions. Social media is a kind of interactive communication and bilateral social network. Various communication contents can be shared and put into mass circulation easily and quickly through social media. These sharings are not only limited to individuals but also happen to groups, institutions, and different constitutions. Their contents consist of any type of written message, audio and video files. We are living in the social media era now. It is not surprising that social media which has extensive communication facilities and massive prevalence is used in politics. Therefore, the use of social media (Facebook) by political parties during the Turkish general elections held on June 7, 2015, has been chosen as our research subject. Four parties namely, AKP, CHP, MHP and HDP who have the majority of votes in Turkey and participate in elections in Konya have been selected for our study. Their provincial centers’ and parliamentary candidates` use of social media (Facebook) on the last three days prior to the election have been examined and subjected to a qualitative analysis by means of content analysis.Keywords: social media, June 7 general elections, politics, Facebook
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