Search results for: labour stability
3228 Postoperative Wound Infections Following Caesarean Section in Obese Patients
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Introduction: Obesity, defined as a Body Mass Index (BMI) of more than or equal to 30kg/m, is associated with an increased risk of complications during pregnancy and delivery. During labour, obese mothers often require greater intervention and have higher rates of caesarean section. Despite a low overall rate of serious complications following caesarean section, a high BMI predisposes to a higher risk of postoperative complications. Our study, therefore, aimed to investigate the impact of antenatal obesity on adverse outcomes following caesarean section, particularly wound-related infections. Materials and Methods: A retrospective cohort study of all caesarean deliveries during the first quarter of a chosen year was undertaken in our hospital, which is a tertiary referral centre with > 12,000 deliveries per year. Patients’ health records and data from our hospital’s electronic labour and delivery database were reviewed. Data analysis was performed using the Statistical Package for the Social Sciences (SPSS), and odds ratios plus adjusted odd ratios were calculated with 95% confidence intervals (CI). Results: A total of 1829 deliveries were reviewed during our study period. Of these, 180 (9.8%) patients were obese. The rate of caesarean delivery was 48.9% in obese patients versus 28.1% in non-obese patients. Post-operatively, 17% of obese patients experienced wound infection versus 0.2% of non-obese patients. Obese patients were also more likely to experience major postpartum haemorrhage (4.6% vs. 0.2%) and postpartum pyrexia (18.2% vs. 5.0%) in comparison to non-obese patients. Conclusions: Obesity is a significant risk factor in the development of postoperative complications following caesarean section. Wound infection remains a major concern for obese patients undergoing major surgery and results in extensive morbidity during the postnatal period. Postpartum infection can prolong recovery and affect maternal mental health, leading to reduced perinatal bonding with long-term implications on breastfeeding and parenting confidence. This study supports the need for the development of standardized protocols specifically for obese patients undergoing caesarean section. Multidisciplinary team care, in conjunction with anaesthesia, family physicians, and plastic surgery counterparts, early on in the antenatal journey, may be beneficial where wound complications are anticipated and to minimize the burden of postoperative infection in obese mothers.Keywords: pregnancy, obesity, caesarean, infection
Procedia PDF Downloads 803227 Decent Work Agenda in the Philippines: A Capacity Assessment
Authors: Dianne Lyneth Alavado
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At the turn of the millennium, development paradigms in the international scene revolved around one goal: elimination of global poverty without comprising human rights. One measure which achieved high endorsement and visibility in the world of work is the Decent Work Agenda (DWA) championed by the United Nation’s (UN) specialized agency for work, the International Labour Organization (ILO). The DWA has been thoroughly promoted and recommended as an ingredient of development planning and a poverty reduction strategy, particularly in developing countries such as the Philippines. The global imperative of economic growth is measurable not only in the numbers raked in by countries in terms of expanding economy but also by the development and realization of the full capacities of their people. Decent work (DW), as an outcome and not just a development approach, promises poverty eradication by means of providing both quantity and quality work that is accompanied by rights, representation, and protection. As a party to these international pacts, the Philippines is expected to heed the call towards a world free from poverty through well-endorsed measures such as the DWA with the aid of multilateral and donor organizations such as the ILO. This study aims to assess the capacity and readiness of the Philippines to achieve the goals of the DWA. This is a qualitative research using the sociological and juridical lens in the desk analysis of existing Philippine laws, policies, and programs vis-à-vis decent work indicators set forth by the ILO. Interview with experts on the Philippine labor situation is conducted for further validation. The paper identifies gaps within the Philippine legal system and its collection of laws, acts, presidential decrees, department orders and other policy instruments aimed towards achieving the goals of the DWA. Among the major findings of this paper are: the predisposition of Philippine labor laws towards the formal sector; the need for alternative solutions for the informal sector veering away from the usual dole-outs and livelihood projects; the needs for evaluation of policies and programs that are usually self-evaluated; the minimal reach of the labour inspectorate which ensures decent work; and the lack of substantial penalty for non-compliance with labor laws. The paper concludes with policy implications and recommendations towards addressing the potholes on the road to Decent Work.Keywords: decent work agenda, labor laws, millennium development goals, poverty eradication, sustainable development goal
Procedia PDF Downloads 2733226 Investigation of the Effect of Plasticization Temperature on Polymer Thin Film Stability through Spin Coating Process
Authors: Bilge Bozdogan, Selda T. Sendogdular, Levent Sendogdular
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We report a technique to control chain conformation during the plasticization process to achieve homogeneous and stable thin films, which allows to reduce post-process annealing times along with enhanced properties like controlled irreversible adsorbed layer (Guiselin brushes) formation. In this study, spin coating temperature was considered as a parameter; hence, all equipment, including the spin coater, substrate, vials, and the solution, was kept inside the same heated fume hood where solution was spin-coated after the temperature was stabilized at a desired value. AFM and SEM results revealed severe difference for solid and air interface between ambient and temperature-controlled samples, which suggest that enthalpic contribution dynamically helps to control film stability in a way where chain entanglements and conformational restrictions are avoided before film growing and allowing to control grafting density through spin coating temperature. The adsorbed layer was also characterized with SEM and Raman-spectroscopy technique right after seeding the adsorbed layer with gold nanoparticles. Stabilized gold nanoparticles and their surface distribution manifest the existence of a controllable polymer brush structure. Acknowledgments: This study was funded by Erciyes University Scientific Research Projects (BAP) Funding(Project ID:10058)Keywords: chain stability, Guiselin brushes, polymer thin film, spin coating temperature
Procedia PDF Downloads 2133225 Causes of Nigeria Unrest and Conflict Situation
Authors: Victor Osaghae
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In 2005, the CIA published a report warning that Nigeria, the seventh most populous country in the world, could disintegrate within 15 years. Nigeria experiences civil unrest, violence and strikes. Nigeria has one of the highest rates of internal violence in the world, only unlike others with similar levels of bloodshed such as Colombia or Chechnya, there is not a civil war going on. The types of unrest observed in Nigeria from literatures consulted can be categorized into five namely: religious, social, political, labour, and communal or ethnic unrests. The cuases of the unrests are as follows: injustice, unemployment, religious intolerance, illiteracy and government not filling agreements reached with unions. The cost due to these unrests cannot be quantified because it affects human, material/properties and money.Keywords: unrest, conflicts, Boko Haram, disturbance
Procedia PDF Downloads 3863224 Modelling the Spread of HIV/AIDS Epidemic with Condom Campaign and Treatment
Authors: Marsudi, Noor Hidayat, Ratno Bagus Edy Wibowo
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This paper considers a deterministic model for the transmission dynamics of HIV/AIDS in which condom campaign and treatment are both important for the disease management. In modelling of the spread of AIDS, the population is divided into six subpopulations, namely susceptible population, susceptible population who change their behavior due to education condom campaign, infected population, pre-AIDS population, treated population and full-blown AIDS population. We calculate the effective reproduction number using the next generation matrix method and investigate the existence and stability of the equilibrium points. A sensitivity analysis discovers parameters that have a high impact on effective reproduction number and should be targeted by intervention strategies. Numerical simulations are given to illustrate and verify our analytic results.Keywords: HIV/AIDS, condom campaign, antiretroviral treatment, effective reproduction number, stability and sensitivity analysis
Procedia PDF Downloads 2653223 Modification of Date Palm Leaflets Fibers Used as Thermoplastic Reinforcement
Authors: K. Almi, S.Lakel, A. Benchabane, A. Kriker
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The fiber–matrix compatibility can be improved if suitable enforcements are chosen. Whenever the reinforcements have more thermal stability, they can resist to the main processes for wood–thermoplastic composites. This paper is an investigation of effect of different treatment process on the mechanical proprieties and on the thermal stability of date palm leaflets fibers with a view to improve the date palm fiber proprieties used as reinforcement of thermoplastic materials which main processes require extrusion, hot press. To compare the effect of alkali and acid treatment on the date palm leaflets fiber properties, different treatment were used such as Sodium hydroxide NaOH solution, aluminium chloride AlCl3 and acid treatment with HCL solution. All treatments were performed at 70°C for 4h and 48 h. The mechanical performance (tensile strength and elongation) is affected by immersion time in alkaline and acid solutions. The reduction of the tensile strength and elongation of fibers at 48h was higher in acid treatment than in alkali treatment at high concentration. No significant differences were observed in mechanical and thermal proprieties of raw fibers and fibers submerged in AlCl3 at low concentration 1% for 48h. Fibers treated by NaOH at 6% for 4h showed significant increase in the mechanical proprieties and thermal stability of date palm leaflets fibers. Hence, soda treatment is necessary to improve the fibers proprieties and consequently optimize the composite performance.Keywords: date palm fibers, surface treatments, thermoplastic composites, thermal analysis
Procedia PDF Downloads 3403222 Sliding Mode Control of Autonomous Underwater Vehicles
Authors: Ahmad Forouzantabar, Mohammad Azadi, Alireza Alesaadi
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This paper describes a sliding mode controller for autonomous underwater vehicles (AUVs). The dynamic of AUV model is highly nonlinear because of many factors, such as hydrodynamic drag, damping, and lift forces, Coriolis and centripetal forces, gravity and buoyancy forces, as well as forces from thruster. To address these difficulties, a nonlinear sliding mode controller is designed to approximate the nonlinear dynamics of AUV and improve trajectory tracking. Moreover, the proposed controller can profoundly attenuate the effects of uncertainties and external disturbances in the closed-loop system. Using the Lyapunov theory the boundedness of AUV tracking errors and the stability of the proposed control system are also guaranteed. Numerical simulation studies of an AUV are included to illustrate the effectiveness of the presented approach.Keywords: lyapunov stability, autonomous underwater vehicle, sliding mode controller, electronics engineering
Procedia PDF Downloads 6073221 Development of Metal-Organic Frameworks-Type Hybrid Functionalized Materials for Selective Uranium Extraction
Authors: Damien Rinsant, Eugen Andreiadis, Michael Carboni, Daniel Meyer
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Different types of materials have been developed for the solid/liquid uranium extraction processes, such as functionalized organic polymers, hybrid silica or inorganic adsorbents. In general, these materials exhibit a moderate affinity for uranyl ions and poor selectivity against impurities like iron, vanadium or molybdenum. Moreover, the structural organization deficiency of these materials generates ion diffusion issues inside the material. Therefore, the aim of our study is to developed efficient and organized materials, stable in the acid media encountered in uranium extraction processes. Metal organic frameworks (MOFs) are hybrid crystalline materials consisting of an inorganic part (cluster or metal ions) and tailored organic linkers connected via coordination bonds. These hierarchical materials have exceptional surface area, thermal stability and a large variety of tunable structures. However, due to the reversibility of constitutive coordination bonds, MOFs have moderate stability in strongly complexing or acidic media. Only few of them are known to be stable in aqueous media and only one example is described in strong acidic media. However, these conditions are very often encountered in the environmental pollution remediation of mine wastewaters. To tackle the challenge of developing MOFs adapted for uranium extraction from acid mine waters, we have investigated the stability of several materials. To ensure a good stability we have synthetized and characterized different materials based on highly coordinated metal clusters, such as LnOFs and Zirconium based materials. Among the latter, the UiO family shows a great stability in sulfuric acid media even in the presence of 1.4 M sodium sulfate at pH 2. However, the stability in phosphoric media is reduced due to the high affinity between zirconium and phosphate ligand. Based on these results, we have developed a tertiary amine functionalized MOF denoted UiO-68-NMe2 particularly adapted for the extraction of anionic uranyl (VI) sulfate complexes mainly present in the acid mine solutions. The adsorption capacity of the material has been determined upon varying total sulfate concentration, contact time and uranium concentration. The extraction tests put in evidence different phenomena due to the complexity of the extraction media and the interaction between the MOF and sulfate anion. Finally, the extraction mechanisms and the interaction between uranyl and the MOF structure have been investigated. The functionalized material UiO-68-NMe2 has been characterized in the presence and absence of uranium by FT-IR, UV and Raman techniques. Moreover, the stability of the protonated amino functionalized MOF has been evaluated. The synthesis, characterization and evaluation of this type of hybrid material, particularly adapted for uranium extraction in sulfuric acid media by an anionic exchange mechanism, paved the way for the development of metal organic frameworks functionalized by different other chelating motifs, such as bifunctional ligands showing an enhanced affinity and selectivity for uranium in acid and complexing media. Work in this direction is currently in progress.Keywords: extraction, MOF, ligand, uranium
Procedia PDF Downloads 1583220 Localized Meshfree Methods for Solving 3D-Helmholtz Equation
Authors: Reza Mollapourasl, Majid Haghi
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In this study, we develop local meshfree methods known as radial basis function-generated finite difference (RBF-FD) method and Hermite finite difference (RBF-HFD) method to design stencil weights and spatial discretization for Helmholtz equation. The convergence and stability of schemes are investigated numerically in three dimensions with irregular shaped domain. These localized meshless methods incorporate the advantages of the RBF method, finite difference and Hermite finite difference methods to handle the ill-conditioning issue that often destroys the convergence rate of global RBF methods. Moreover, numerical illustrations show that the proposed localized RBF type methods are efficient and applicable for problems with complex geometries. The convergence and accuracy of both schemes are compared by solving a test problem.Keywords: radial basis functions, Hermite finite difference, Helmholtz equation, stability
Procedia PDF Downloads 993219 Ongoing Gender-Based Challenges in Post-2015 Development Agenda: A Comparative Study between Qatar and Arab States
Authors: Abdel-Samad M. Ali, Ali A. Hadi Al-Shawi
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Discrimination against women and girls impairs progress in all domains of development articulated either in the framework of Millennium Development Goals (MDGs) or in the Post-2015 Development Agenda. Paper aspires to create greater awareness among researchers and policy makers of the challenges posed by gender gaps and the opportunities created by reducing them within the Arab region. The study reveals how Arab countries are closing in on gender-oriented targets of the third and fifth MDGs. While some countries can claim remarkable achievements particularly in girls’ equality in education, there is still a long way to go to keep Arab’s commitments to current and future generations in other countries and subregions especially in the economic participation or in the political empowerment of women. No country has closed or even expected to close the economic participation gap or the political empowerment gap. This should provide the incentive to keep moving forward in the Post-2015 Agenda. Findings of the study prove that while Arab states have uneven achievements in reducing maternal mortality, Arab women remain at a disadvantage in the labour market. For Arab region especially LDCs, improving maternal health is part of the unmet agenda for the post-2015 period and still calls for intensified efforts and procedures. While antenatal care coverage is improving across the Arab region, progress is marginal in LDCs. To achieve proper realization of gender equality and empowerment of women in the Arab region in the post-2015 agenda, the study presents critical key challenges to be addressed. These challenges include: Negative cultural norms and stereotypes; violence against women and girls; early marriage and child labour; women’s limited control over their own bodies; limited ability of women to generate their own income and control assets and property; gender-based discrimination in law and in practice; women’s unequal participation in private and public decision making autonomy; and limitations in data. However, in all Arab states, gender equality must be integrated as a goal across all issues, particularly those that affect the future of a country.Keywords: gender, equity, millennium development goals, post-2015 development agenda
Procedia PDF Downloads 2613218 Polypyrrole as Bifunctional Materials for Advanced Li-S Batteries
Authors: Fang Li, Jiazhao Wang, Jianmin Ma
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The practical application of Li-S batteries is hampered due to poor cycling stability caused by electrolyte-dissolved lithium polysulfides. Dual functionalities such as strong chemical adsorption stability and high conductivity are highly desired for an ideal host material for a sulfur-based cathode. Polypyrrole (PPy), as a conductive polymer, was widely studied as matrixes for sulfur cathode due to its high conductivity and strong chemical interaction with soluble polysulfides. Thus, a novel cathode structure consisting of a free-standing sulfur-polypyrrole cathode and a polypyrrole coated separator was designed for flexible Li-S batteries. The PPy materials show strong interaction with dissoluble polysulfides, which could suppress the shuttle effect and improve the cycling stability. In addition, the synthesized PPy film with a rough surface acts as a current collector, which improves the adhesion of sulfur materials and restrain the volume expansion, enhancing the structural stability during the cycling process. For further enhancing the cycling stability, a PPy coated separator was also applied, which could make polysulfides into the cathode side to alleviate the shuttle effect. Moreover, the PPy layer coated on commercial separator is much lighter than other reported interlayers. A soft-packaged flexible Li-S battery has been designed and fabricated for testing the practical application of the designed cathode and separator, which could power a device consisting of 24 light-emitting diode (LED) lights. Moreover, the soft-packaged flexible battery can still show relatively stable cycling performance after repeated bending, indicating the potential application in flexible batteries. A novel vapor phase deposition method was also applied to prepare uniform polypyrrole layer coated sulfur/graphene aerogel composite. The polypyrrole layer simultaneously acts as host and adsorbent for efficient suppression of polysulfides dissolution through strong chemical interaction. The density functional theory (DFT) calculations reveal that the polypyrrole could trap lithium polysulfides through stronger bonding energy. In addition, the deflation of sulfur/graphene hydrogel during the vapor phase deposition process enhances the contact of sulfur with matrixes, resulting in high sulfur utilization and good rate capability. As a result, the synthesized polypyrrole coated sulfur/graphene aerogel composite delivers a specific discharge capacity of 1167 mAh g⁻¹ and 409.1 mAh g⁻¹ at 0.2 C and 5 C respectively. The capacity can maintain at 698 mAh g⁻¹ at 0.5 C after 500 cycles, showing an ultra-slow decay rate of 0.03% per cycle.Keywords: polypyrrole, strong chemical interaction, long-term stability, Li-S batteries
Procedia PDF Downloads 1403217 Quintic Spline Method for Variable Coefficient Fourth-Order Parabolic Partial Differential Equations
Authors: Reza Mohammadi, Mahdieh Sahebi
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We develop a method based on polynomial quintic spline for numerical solution of fourth-order non-homogeneous parabolic partial differential equation with variable coefficient. By using polynomial quintic spline in off-step points in space and finite difference in time directions, we obtained two three level implicit methods. Stability analysis of the presented method has been carried out. We solve four test problems numerically to validate the proposed derived method. Numerical comparison with other existence methods shows the superiority of our presented scheme.Keywords: fourth-order parabolic equation, variable coefficient, polynomial quintic spline, off-step points, stability analysis
Procedia PDF Downloads 3663216 Parametric Analysis of Lumped Devices Modeling Using Finite-Difference Time-Domain
Authors: Felipe M. de Freitas, Icaro V. Soares, Lucas L. L. Fortes, Sandro T. M. Gonçalves, Úrsula D. C. Resende
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The SPICE-based simulators are quite robust and widely used for simulation of electronic circuits, their algorithms support linear and non-linear lumped components and they can manipulate an expressive amount of encapsulated elements. Despite the great potential of these simulators based on SPICE in the analysis of quasi-static electromagnetic field interaction, that is, at low frequency, these simulators are limited when applied to microwave hybrid circuits in which there are both lumped and distributed elements. Usually the spatial discretization of the FDTD (Finite-Difference Time-Domain) method is done according to the actual size of the element under analysis. After spatial discretization, the Courant Stability Criterion calculates the maximum temporal discretization accepted for such spatial discretization and for the propagation velocity of the wave. This criterion guarantees the stability conditions for the leapfrogging of the Yee algorithm; however, it is known that for the field update, the stability of the complete FDTD procedure depends on factors other than just the stability of the Yee algorithm, because the FDTD program needs other algorithms in order to be useful in engineering problems. Examples of these algorithms are Absorbent Boundary Conditions (ABCs), excitation sources, subcellular techniques, grouped elements, and non-uniform or non-orthogonal meshes. In this work, the influence of the stability of the FDTD method in the modeling of concentrated elements such as resistive sources, resistors, capacitors, inductors and diode will be evaluated. In this paper is proposed, therefore, the electromagnetic modeling of electronic components in order to create models that satisfy the needs for simulations of circuits in ultra-wide frequencies. The models of the resistive source, the resistor, the capacitor, the inductor, and the diode will be evaluated, among the mathematical models for lumped components in the LE-FDTD method (Lumped-Element Finite-Difference Time-Domain), through the parametric analysis of Yee cells size which discretizes the lumped components. In this way, it is sought to find an ideal cell size so that the analysis in FDTD environment is in greater agreement with the expected circuit behavior, maintaining the stability conditions of this method. Based on the mathematical models and the theoretical basis of the required extensions of the FDTD method, the computational implementation of the models in Matlab® environment is carried out. The boundary condition Mur is used as the absorbing boundary of the FDTD method. The validation of the model is done through the comparison between the obtained results by the FDTD method through the electric field values and the currents in the components, and the analytical results using circuit parameters.Keywords: hybrid circuits, LE-FDTD, lumped element, parametric analysis
Procedia PDF Downloads 1513215 Complex Dynamics of a Four Species Food-Web Model: An Analysis through Beddington-Deangelis Functional Response in the Presence of Additional Food
Authors: Surbhi Rani, Sunita Gakkhar
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The four-dimensional food web system consisting of two prey species for a generalist middle predator and a top predator is proposed and investigated. The middle predator is predating both the prey species with a modified Holling type-II functional response. The food web model is found to be well-posed, bounded, and dissipative. The proposed model's essential dynamical features are studied in terms of local stability. The four species' survival is explored, and persistence conditions are established. The numerical simulations reveal the persistence in the form of a chaotic attractor or stable focus. The conclusion is that providing additional food to the middle predator may help to control the food chain's chaos.Keywords: predator-prey model, existence of equilibrium points, local stability, chaos, numerical simulations
Procedia PDF Downloads 1063214 Effect of Low Temperature on Structure and RNA Binding of E.coli CspA: A Molecular Dynamics Based Study
Authors: Amit Chaudhary, B. S. Yadav, P. K. Maurya, A. M., S. Srivastava, S. Singh, A. Mani
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Cold shock protein A (CspA) is major cold inducible protein present in Escherichia coli. The protein is involved in stabilizing secondary structure of RNA by working as chaperone during cold temperature. Two RNA binding motifs play key role in the stabilizing activity. This study aimed to investigate implications of low temperature on structure and RNA binding activity of E. coli CspA. Molecular dynamics simulations were performed to compare the stability of the protein at 37°C and 10 °C. The protein was mutated at RNA binding motifs and docked with RNA to assess the stability of both complexes. Results suggest that CspA as well as CspA-RNA complex is more stable at low temperature. It was also confirmed that RNP1 and RNP2 play key role in RNA binding.Keywords: CspA, homology modelling, mutation, molecular dynamics simulation
Procedia PDF Downloads 3713213 Design and Development of Compact 1KW Floating Battery Discharge Regulator
Authors: A. Sreedevi, G. Anantaramu
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The present space research organizations are striving towards the development of lighter, smaller, more efficient, low cost, and highly reliable power supply. Switch mode power supplies (SMPS) overcome the demerits of linear power supplies such as low efficiency, difficulties in thermal management, and in boosting the output voltage. Space applications require a constant DC voltage to supply its load. As the load varies, the battery terminal voltage tends to vary accordingly. To avoid this variation in the load terminal voltage, a DC-DC regulator is required. The conventional regulator for space applications is isolated boost topology. The proposed topology uses an interleaved push-pull converter with a current doubler secondary to reduce the EMI issues and increase efficiency. The proposed topology uses a floating technique where the converter derives power from the battery and generates only the voltage that is required to fill the gap between the bus and the battery voltage. The direct voltage sense and current loop provide tight regulation of output and better stability. Converter is designed with 50 kHz switching frequency using UC 1825 PWM controller employing both voltage and peak current mode control. Experimental tests have been carried out on the converter under different input and load conditions to validate the design. The experimental results showed that the efficiency was greater than 91%. Stability analysis is done using venable stability analyzer.Keywords: push pull converter, current doubler, converter, PWM control
Procedia PDF Downloads 1013212 Stability or Instabilty? Triplet Deficit Analysis In Turkey
Authors: Zeynep Karaçor, Volkan Alptekin, Gökhan Akar, Tuba Akar
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This paper aims to review the phenomenon of triplet deficit which is called interaction of budget balance that make up the overall balance of the economy, investment savings balance and current accounts balance in terms of Turkey. In this paper, triplet deficit state in Turkish economy has been analyzed with vector autoregressive model and Granger causality test using data covering the period of 1980-2010. According to VAR results, increase in current accounts is perceived on public sector borrowing requirement. These two variables influence each other bilaterally. Therefore, current accounts increase public deficit, whereas public deficit increases current accounts. It is not possible to mention the existence of a short-term Granger causality between variables at issue.Keywords: internal and external deficit, stability, triplet deficit, Turkey economy
Procedia PDF Downloads 3423211 Investigation of Microstructure, Mechanical Properties and Anti-Corrosive Behavior of Al2O3/Cr2O3 Nanocomposite on Zn Rich Bath
Authors: N. Malatji, A. P. I. Popoola
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Zn-Al2O3 and Cr2O3 nanocomposite coatings were successfully produced by electrodeposition technique from chloride acidic bath. Particle loading of Al2O3 (50nm) particles were varied from 5-10 g/L and for Cr2O3(100nm) was 10-20 g/L. Scanning electron microscope (SEM) affixed with energy dispersive spectrometry was used to study the surface morphology and content of the nanoparticles incorporated into the coatings. Microhardness, thermal stability, wear and corrosion behavior of the coatings were also evaluated to study the effect of these nanoparticles on these properties. Zn-Al2O3 nanocomposite was found to exhibit good surface properties especially corrosion resistance. On the other side, Cr2O3 incorporation resulted in the improvement of only mechanical properties. Therefore, Zn-Al2O3 proved to be a better coating for most industrial applications where both chemical and mechanical properties are required.Keywords: electrodeposition, nanocomposite coatings, corrosion, thermal stability, tribology
Procedia PDF Downloads 3873210 Fabrication of Chitosan/Polyacrylonitrile Blend and SEMI-IPN Hydrogel with Epichlorohydrin
Authors: Muhammad Omer Aijaz, Sajjad Haider, Fahad S. Al Mubddal, Yousef Al-Zeghayer, Waheed A. Al Masry
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The present study is focused on the preparation of chitosan-based blend and Semi-Interpenetrating Polymer Network (SEMI-IPN) with polyacrylonitrile (PAN). Blend Chitosan/Polyacrylonitrile (PAN) hydrogel films were prepared by solution blending and casting technique. Chitosan in the blend was cross-linked with epichlorohydrin (ECH) to prepare SEMI-IPN. The developed Chitosan/PAN blend and SEMI-IPN hydrogels were characterized with SEM, FTIR, TGA, and DSC. The result showed good miscibility between chitosan and PAN, crosslinking of chitosan in the blend, and improved thermal properties for SEMI-IPN. The swelling of the different blended and SEMI-IPN hydrogels samples were examined at room temperature. Blend (C80/P20) sample showed highest swelling (2400%) and fair degree of stability (28%) whereas SEMI-IPN hydrogel exhibited relatively low degree of swelling (244%) and high degree of aqueous stability (85.5%).Keywords: polymer hydrogels, chitosan, SEMI-IPN, polyacrylonitrile, epichlorohydrin
Procedia PDF Downloads 3713209 How Defining the Semi-Professional Journalist Is Creating Nuance and a Familiar Future for Local Journalism
Authors: Ross Hawkes
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The rise of hyperlocal journalism and its role in the wider local news ecosystem has been debated across both industry and academic circles, particularly via the lens of structures, models, and platforms. The nuances within this sphere are now allowing for the semi-professional journalist to emerge as a key component of the landscape at the fringes of journalism. By identifying and framing the labour of these individuals against a backdrop of change within the professional local newspaper publishing industry, it is possible to address wider debates around the ways in which participants enter and exist in the space between amateur and professional journalism. Considerations around prior experience and understanding allow us to better shape and nuance the hyperlocal landscape in order to understand the challenges and opportunities facing local news via this emergent form of semi-professional journalistic production. The disruption to local news posed by the changing nature of audiences, long-established methods of production, the rise of digital platforms, and increased competition in the online space has brought questions around the very nature and identity of local news, as well as the uncertain future and precarity which surrounds it. While the hyperlocal sector has long been associated as a potential future direction for local journalism through an alternative approach to reporting and as a mechanism for participants to pass between amateurism towards professionalism, there is now a semi-professional space being occupied in a different way. Those framed as semi-professional journalists are not necessarily transiting through this space at the fringes of the professional industry; instead, they are occupying and claiming the space as an entity within itself. By framing the semi-professional journalist through a lens of prior experience and knowledge of the sector, it is possible to identify how their motivations vary from the traditional metrics of financial gain, personal progression, or a sense of civic or community duty. While such factors may be by-products of their labour, the desire of such reporters to recreate and retain experiences and values from their past as a participant or consumer is the central basis of the framework to define the semi-professional journalist. Through understanding the motivations, aims and factors shaping the semi-professional journalist within the wider journalism and hyperlocal journalism debates and landscape, it will be possible to better frame the role they can play in sustaining the longer term provision of local news and addressing broader issues and factors within the sector.Keywords: hyperlocal, journalism, local news, semi-professionalism
Procedia PDF Downloads 283208 Foamability and Foam Stability of Gelatine-Sodium Dodecyl Sulfate Solutions
Authors: Virginia Martin Torrejon, Song Hang
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Gelatine foams are widely explored materials due to their biodegradability, biocompatibility, and availability. They exhibit outstanding properties and are currently subject to increasing scientific research due to their potential use in different applications, such as biocompatible cellular materials for biomedical products or biofoams as an alternative to fossil-fuel-derived packaging. Gelatine is a highly surface-active polymer, and its concentrated solutions usually do not require surfactants to achieve low surface tension. Still, anionic surfactants like sodium dodecyl sulfate (SDS) strongly interact with gelatine, impacting its viscosity and rheological properties and, in turn, their foaming behaviour. Foaming behaviour is a key parameter for cellular solids produced by mechanical foaming as it has a significant effect on the processing and properties of cellular materials. Foamability mainly impacts the density and the mechanical properties of the foams, while foam stability is crucial to achieving foams with low shrinkage and desirable pore morphology. This work aimed to investigate the influence of SDS on the foaming behaviour of concentrated gelatine foams by using a dynamic foam analyser. The study of maximum foam height created, foam formation behaviour, drainage behaviour, and foam structure with regard to bubble size and distribution were carried out in 10 wt% gelatine solutions prepared at different SDS/gelatine concentration ratios. Comparative rheological and viscometry measurements provided a good correlation with the data from the dynamic foam analyser measurements. SDS incorporation at optimum dosages and gelatine gelation led to highly stable foams at high expansion ratios. The viscosity increase of the hydrogel solution at SDS content increased was a key parameter for foam stabilization. In addition, the impact of SDS content on gelling time and gel strength also considerably impacted the foams' stability and pore structure.Keywords: dynamic foam analyser, gelatine foams stability and foamability, gelatine-surfactant foams, gelatine-SDS rheology, gelatine-SDS viscosity
Procedia PDF Downloads 1513207 International Conference on Islam and Democracy – Religion and Political Stability in Indonesia
Authors: Mariel Encar H. Uy, Paula Marie G. Pacle
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The purpose of this research is to present a Single Country Comparative Contextual Description Study of Strong Islamic Influences in Relation to the Politics of Republic of Indonesia. This paper recognizes that even the coalition of secular and moderate Islamic parties protect the minority rights of all the constituents, Islam is still the dominant religion among the other recognized religions in Indonesia (Christianity, Hinduism and Buddhism). In this study, it will also detail the involvement on the religions’ beliefs and techniques; participation of political actors, depending on what religion they belong and adhere to; the tensions whenever the government interferes with Islamists and other religions; the government’s solution or public policies implemented to maintain peace and order of Indonesia. This paper will develop a conceptual framework to describe how the Religion and Political Stability is interdependent with each other.Keywords: diversity of religion in indonesia, secularization in Indonesia, motivations of political actors, voter turnouts based on religion
Procedia PDF Downloads 3323206 Multi-Agent Coverage Control with Bounded Gain Forgetting Composite Adaptive Controller
Authors: Mert Turanli, Hakan Temeltas
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In this paper, we present an adaptive controller for decentralized coordination problem of multiple non-holonomic agents. The performance of the presented Multi-Agent Bounded Gain Forgetting (BGF) Composite Adaptive controller is compared against the tracking error criterion with a Feedback Linearization controller. By using the method, the sensor nodes move and reconfigure themselves in a coordinated way in response to a sensed environment. The multi-agent coordination is achieved through Centroidal Voronoi Tessellations and Coverage Control. Also, a consensus protocol is used for synchronization of the parameter vectors. The two controllers are given with their Lyapunov stability analysis and their stability is verified with simulation results. The simulations are carried out in MATLAB and ROS environments. Better performance is obtained with BGF Adaptive Controller.Keywords: adaptive control, centroidal voronoi tessellations, composite adaptation, coordination, multi robots
Procedia PDF Downloads 3463205 Perovskite Nanocrystals and Quantum Dots: Advancements in Light-Harvesting Capabilities for Photovoltaic Technologies
Authors: Mehrnaz Mostafavi
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Perovskite nanocrystals and quantum dots have emerged as leaders in the field of photovoltaic technologies, demonstrating exceptional light-harvesting abilities and stability. This study investigates the substantial progress and potential of these nano-sized materials in transforming solar energy conversion. The research delves into the foundational characteristics and production methods of perovskite nanocrystals and quantum dots, elucidating their distinct optical and electronic properties that render them well-suited for photovoltaic applications. Specifically, it examines their outstanding light absorption capabilities, enabling more effective utilization of a wider solar spectrum compared to traditional silicon-based solar cells. Furthermore, this paper explores the improved durability achieved in perovskite nanocrystals and quantum dots, overcoming previous challenges related to degradation and inconsistent performance. Recent advancements in material engineering and techniques for surface passivation have significantly contributed to enhancing the long-term stability of these nanomaterials, making them more commercially feasible for solar cell usage. The study also delves into the advancements in device designs that incorporate perovskite nanocrystals and quantum dots. Innovative strategies, such as tandem solar cells and hybrid structures integrating these nanomaterials with conventional photovoltaic technologies, are discussed. These approaches highlight synergistic effects that boost efficiency and performance. Additionally, this paper addresses ongoing challenges and research endeavors aimed at further improving the efficiency, stability, and scalability of perovskite nanocrystals and quantum dots in photovoltaics. Efforts to mitigate concerns related to material degradation, toxicity, and large-scale production are actively pursued, paving the way for broader commercial application. In conclusion, this paper emphasizes the significant role played by perovskite nanocrystals and quantum dots in advancing photovoltaic technologies. Their exceptional light-harvesting capabilities, combined with increased stability, promise a bright future for next-generation solar cells, ushering in an era of highly efficient and cost-effective solar energy conversion systems.Keywords: perovskite nanocrystals, quantum dots, photovoltaic technologies, light-harvesting, solar energy conversion, stability, device designs
Procedia PDF Downloads 953204 Influence of Internal Heat Source on Thermal Instability in a Horizontal Porous Layer with Mass Flow and Inclined Temperature Gradient
Authors: Anjanna Matta, P. A. L. Narayana
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An investigation has been presented to analyze the effect of internal heat source on the onset of Hadley-Prats flow in a horizontal fluid saturated porous medium. We examine a better understanding of the combined influence of the heat source and mass flow effect by using linear stability analysis. The resultant eigenvalue problem is solved by using shooting and Runga-Kutta methods for evaluate critical thermal Rayleight number with respect to various flow governing parameters. It is identified that the flow is switch from stabilizing to destabilizing as the horizontal thermal Rayleigh number is enhanced. The heat source and mass flow increases resulting a stronger destabilizing effect.Keywords: linear stability analysis, heat source, porous medium, mass flow
Procedia PDF Downloads 7193203 Effect of Fatiguing Hip Muscles on Dynamic Posture Control in Recurrent Ankle Sprain
Authors: Radwa El Shorbagy, Alaa El Din Balbaa, Khaled Ayad, Waleed Reda
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Ankle sprain is a common lower limb injury that is complicated by high recurrence rate. The cause of recurrence is not clear; however, changes in motor control have been postulated.Objective: to determine the contribution of proximal hip strategy to dynamic posture control in patients with recurrent ankle sprain. Methods:Fifteen subjects with recurrent ankle sprain (Group A) and fifteen healthy control subjects (Group B) participated in this study. Abductor-adductor as well as flexor-extensor hip musculature control was abolished by fatigue using the Biodex Isokinatic System. Dynamic posture control was measured before and after fatigue by the Biodex Balance System. Results: Repeated measures MANOVA was used to compare within group differences. In group A fatiguing of hip muscles (flexors-extensors and abductors-adductors) lowered overall stability index (OASI), anteroposterior stability index (APSI) and mediolateral stability index (MLSI) significantly (p=0.00) whereas; in group B fatiguing of hip flexors-extensors lowered significantly OASI and APSI only (p= 0.017, 0.010; respectively) while fatiguing of hip abductors-adductors has no significant effect on these variables. Conclusion: fatiguing of hip muscles has a significant deleterious effect on dynamic posture control in patient with recurrent ankle sprain indicating their increased dependence on hip strategy.Keywords: ankle sprain, fatigue hip muscles, dynamic balance, ankle sprain
Procedia PDF Downloads 3533202 Comparison of the Effect of Semi-Rigid Ankle Bracing Performance among Ankle Injured Versus Non-Injured Adolescent Female Hockey Players
Authors: T. J. Ellapen, N. Acampora, S. Dawson, J. Arling, C. Van Niekerk, H. J. Van Heerden
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Objectives: To determine the comparative proprioceptive performance of injured versus non-injured adolescent female hockey players when wearing an ankle brace. Methods: Data were collected from 100 high school players who belonged to the Highway Secondary School KZN Hockey league via voluntary parental informed consent and player assent. Players completed an injury questionnaire probing the prevalence and nature of hockey injuries (March-August 2013). Subsequently players completed a Biodex proprioceptive test with and without an ankle brace. Probability was set at p≤ 0.05. Results: Twenty-two players sustained ankle injuries within the six months (p<0.001). Injured players performed similarly without bracing Right Anterior Posterior Index (RAPI): 2.8±0.9; Right Medial Lateral Index (RMLI): 1.9±0.7; Left Anterior Posterior Index (LAPI) LAPI: 2.7; Left Medial Lateral Index (LMLI): 1.7±0.6) as compared to bracing (RAPI: 2.7±1.4; RMLI: 1.8±0.6; LAPI: 2.6±1.0; LMLI: 1.5±0.6) (p>0.05). However, bracing (RAPI: 2.2±0.8; RMLI: 1.5±0.5; LAPI: 2.4±0.9; MLI: 1.5±0.5) improved the ankle stability of the non-injured group as compared to their unbraced performance (RAPI: 2.5±1.0; RMLI: 1.8±0.8; LAPI: 2.8±1.1; LMLI: 1.8±0.6) (p<0.05). Conclusion: Ankle bracing did not enhance the stability of injured ankles. However ankle bracing has an ergogenic effect enhancing the stability of healthy ankles.Keywords: hockey, proprioception, ankle, bracing
Procedia PDF Downloads 3453201 Arsenic Removal from Drinking Water by Hybrid Hydrogel-Biochar Matrix: An Understanding of Process Parameters
Authors: Vibha Sinha, Sumedha Chakma
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Arsenic (As) contamination in drinking water is a serious concern worldwide resulting in severe health maladies. To tackle this problem, several hydrogel based matrix which selectively uptake toxic metals from contaminated water has increasingly been examined as a potential practical method for metal removal. The major concern in hydrogels is low stability of matrix, resulting in poor performance. In this study, the potential of hybrid hydrogel-biochar matrix synthesized from natural plant polymers, specific for As removal was explored. Various compositional and functional group changes of the elements contained in the matrix due to the adsorption of As were identified. Moreover, to resolve the stability issue in hydrogel matrix, optimum and effective mixing of hydrogel with biochar was studied. Mixing varied proportions of matrix components at the time of digestion process was tested. Preliminary results suggest that partial premixing methods may increase the stability and reduce cost. Addition of nanoparticles and specific catalysts with different concentrations of As(III) and As(V) under batch conditions was performed to study their role in performance enhancement of the hydrogel matrix. Further, effect of process parameters, optimal uptake conditions and detailed mechanism derived from experimental studies were suitably conducted. This study provides an efficient, specific and a low-cost As removal method that offers excellent regeneration abilities which can be reused for value.Keywords: arsenic, catalysts, hybrid hydrogel-biochar, water purification
Procedia PDF Downloads 1873200 Internet Based Teleoperation of the Quad Rotor with Force Feedback Using Smith Predictor
Authors: K. Senthil Kumar, A. Vasumalaikannan
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In this paper, teleoperation of the quadrotor using Internet with Force feedback is addressed. Teleoperation with Force feedback is the ability to remotely control a robot, where contact (obstacle) or environment (wind gust etc) information (force feedback) is communicated from the quadrotor to the master joystick and thus giving the operator a sense of telepresence. The stability and performance of such a teleoperator is highly dependent on the amount of time delay present in the control loop. This problem is further complicated given the fact that for network based communication the time delay is itself time varying and highly non deterministic. In this paper, a novel method using Neural based Smith Predictor at the master side the stability is achieved. The performance of the system even during worst case scenario is within acceptable.Keywords: teleoperation, quadrotor, neural smith predictor, time delay
Procedia PDF Downloads 6133199 Development of Stability Indicating Method and Characterization of Degradation Impurity of Nirmaltrelvir in Its Self-Emulsifying Drug Delivery System
Authors: Ravi Patel, Ravisinh Solanki, Dignesh Khunt
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A stability-indicating reverse phase high performance liquid chromatography (RP-HPLC) method was developed and validated for estimating Nirmatrelvir in its self-emulsifying drug delivery system (SEDDS). The separation of Nirmatrelvir and its degradation products was accomplished by employing an Agilent Zorbax Eclipse plus C18 (250 mm x 4.6 mm, 5 µm) column, through which the mobile phase 5 mM phosphate buffer (pH 4.0) as mobile phase A and Acetonitrile as mobile phase B in a ratio of (40:60 % v/v) was pumped at a flow rate of 1.0 mL/min, through the HPLC system. Chromatographic separation and elution were monitored by a photo-diode array detector at 210 nm. Stress studies have been employed to evaluate this method's ability to indicate stability. Nirmatrelvir was exposed to several stress conditions, such as acid, alkali, oxidative, photolytic, and thermal degradations. Significant degradation was observed during acid and alkali hydrolysis, and the resulting degradation product was successfully separated from the Nirmatrelvir peak, preventing any interference. Furthermore, the primary degradant produced under alkali degradation conditions was identified using UPLC-ESI-TQ-MS/MS. The method was validated in accordance with the International Council on Harmonization (ICH) and found to be selective, precise, accurate, linear, and robust. The apparent permeability of Nirmatrelvir SEDDS was 4.20 ± 0.21×10-6 cm/sec, and the average proportion of free drug recovered was 0.5%. The method developed in this study was feasible and accurate for routine quality control evaluation of Nirmatrelvir SEDDS.Keywords: Nirmatrelvir, SEDDS, degradation study, HPLC, LC-MS/MS
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