Search results for: line parameters

Authors: Ji Zhou, Jung Hee Seo, Rajat Mittal

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Fish move in groups for foraging, reproduction, predator protection, and hydrodynamic efficiency. Schooling's predator protection involves the "many eyes" theory, which increases predator detection probability in a group. Reduced visual signature in a group scales with school size, offering per-capita protection. The ‘confusion effect’ makes it hard for predators to target prey in a group. These benefits, however, all focus on vision-based sensing, overlooking sound-based detection. Fish, including predators, possess sophisticated sensory systems for pressure waves and underwater sound. The lateral line system detects acoustic waves, while otolith organs sense infrasound, and sharks use an auditory system for low-frequency sounds. Among sound generation mechanisms of fish, the mechanism of dipole sound relates to hydrodynamic pressure forces on the body surface of the fish and this pressure would be affected by group swimming. Thus, swimming within a group could affect this hydrodynamic noise signature of fish and possibly serve as an additional protection afforded by schooling, but none of the studies to date have explored this effect. BAUVs with fin-like propulsors could reduce acoustic noise without compromising performance, addressing issues of anthropogenic noise pollution in marine environments. Therefore, in this study, we used our in-house immersed-boundary method flow and acoustic solver, ViCar3D, to simulate fish schools consisting of four swimmers in the classic ‘diamond’ configuration and discussed the feasibility of yielding higher swimming efficiency and controlling far-field sound signature of the school. We examine the effects of the relative phase of fin flapping of the swimmers and the simulation results indicate that the phase of the fin flapping is a dominant factor in both thrust enhancement and the total sound radiated into the far-field by a group of swimmers. For fish in the “diamond” configuration, a suitable combination of the relative phase difference between pairs of leading fish and trailing fish can result in better swimming performance with significantly lower hydroacoustic noise.

Keywords: fish schooling, biopropulsion, hydrodynamics, hydroacoustics

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Authors: Pascal François Faye, Baye Mor Sall, Bineta Dembele, Jeanne Ana Awa Faye

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In agriculture, estimating crop yields is key to improving productivity and decision-making processes such as financial market forecasting and addressing food security issues. The main objective of this paper is to have tools to predict and improve the accuracy of crop yield forecasts using machine learning (ML) algorithms such as CART , KNN and SVM . We developed a mobile app and a web app that uses these algorithms for practical use by farmers. The tests show that our system (collection and deployment architecture, web application and mobile application) is operational and validates empirical knowledge on agro-climatic parameters in addition to proactive decision-making support. The experimental results obtained on the agricultural data, the performance of the ML algorithms are compared using cross-validation in order to identify the most effective ones following the agricultural data. The proposed applications demonstrate that the proposed approach is effective in predicting crop yields and provides timely and accurate responses to farmers for decision support.

Keywords: prediction, machine learning, artificial intelligence, digital agriculture

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Authors: Maher Gzam, Noureddine Elmejdoub, Younes Jedoui

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Physical parameters involved in the depositional process on stromatolites, which grow in salt marsh domain, are elucidated in this study. Stromatolites start to grow where surface altimetry of the intertidal flat is high enough to reduce water cover (above mean high tide) and to guarantee a lamellar stream flow. Stromatolite aggrades as a thick laminated layer (stromatolite package) allowing pioneer vascular plants (Salicornia Arabica) to colonize this elevated area (6 cm a.m.s.l). In turn halophytic plant, regularly flooded on spring tide, reduce hydrodynamics velocities causing deposition of sediment, as a result, intertidal zone shift on the flat surface with an expanded marsh domain. This positive feedback invokes self organization between stromatolite growth, vegetation proliferation and deposition of sediment and may be applicable to ancient progradational sequence.

Keywords: stromatolites, marsh, deposition of sediment, aggradation, progradation, gulf of Gabes, Tunisia

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Authors: Henni Mansour Abdelwaheb

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This study discusses the design of a bounded position/force feedback controller developed to ensure position and force tracking for bilateral teleoperation arms operating with variable delay, and actuator saturation. Also, an adaptive robust Radial Basis Function (RBF) neural network is used to estimate the environment torque. The parameters of the environment torque are then sent from the slave site to the master site as a non-power signal to avoid passivity problems. Moreover, a nonlinear function is applied to each controller term as a smooth saturation function, providing a bounded control signal and preserving the system’s actuators. Lastly, the Lyapunov approach demonstrates the global stability of the controlled system, and numerical experiment results further confirm the validity of the presented strategy.

Keywords: teleoperation manipulators system, time-varying delay, actuator saturation, adaptive robust rbf neural network approximation, uncertainties

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Authors: Getachew Tilahun, Oluwole Makinde, David Malonza

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We propose and analyze a non-linear mathematical model for the transmission dynamics of pneumonia disease in a population of varying size. The deterministic compartmental model is studied using stability theory of differential equations. The effective reproduction number is obtained and also the local and global asymptotically stability conditions for the disease free and as well as for the endemic equilibria are established. The model exhibit a backward bifurcation and the sensitivity indices of the basic reproduction number to the key parameters are determined. Using Pontryagin’s maximum principle, the optimal control problem is formulated with three control strategies; namely disease prevention through education, treatment and screening. The cost effectiveness analysis of the adopted control strategies revealed that the combination of prevention and treatment is the most cost effective intervention strategies to combat the pneumonia pandemic. Numerical simulation is performed and pertinent results are displayed graphically.

Keywords: cost effectiveness analysis, optimal control, pneumonia dynamics, stability analysis, numerical simulation

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Authors: Ilker Sönmez, Mustafa Kaplan

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The wastes that come out as a result of agricultural productions are disposed randomly and always by burning. Agricultural wastes have a great volume and agricultural wastes cause environmental pollution. Spent mushroom compost and cut flower carnation wastes have a serious potential in Turkey and especially in Antalya. One of the best evaluation methods of agricultural wastes is composting methods and so agricultural wastes transformed for a new product. In this study, agricultural wastes were evaluated the effects of compost and organic material on soil pH, EC, soil organic matter, and macro-micro nutrient contents of soil that it growth carnation. The effects of compost applications on soils were found to be statistically significant. Organic material applications have caused an increase in all physical and chemical parameters except for pH that pH decreased with compost added in soils. The best results among the compost applications were determined R1 compost that R1 compost included %75 Carnation Wastes + %25 Spent Mushroom Compost. The structural properties of soils can be improved with reusing of agricultural wastes by composting so it can be provided that decreasing the harmful effects of organic wastes on the environment.

Keywords: agricultural wastes, carnation wastes, composting, organic material, spent mushroom compost

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Authors: M. D. Haneef, R. B. Randall, Z. Peng

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Journal bearings used in IC engines are prone to premature failures and are likely to fail earlier than the rated life due to highly impulsive and unstable operating conditions and frequent starts/stops. Vibration signature extraction and wear debris analysis techniques are prevalent in the industry for condition monitoring of rotary machinery. However, both techniques involve a great deal of technical expertise, time and cost. Limited literature is available on the application of these techniques for fault detection in reciprocating machinery, due to the complex nature of impact forces that confounds the extraction of fault signals for vibration based analysis and wear prediction. This work is an extension of a previous study, in which an engine simulation model was developed using a MATLAB/SIMULINK program, whereby the engine parameters used in the simulation were obtained experimentally from a Toyota 3SFE 2.0 litre petrol engines. Simulated hydrodynamic bearing forces were used to estimate vibrations signals and envelope analysis was carried out to analyze the effect of speed, load and clearance on the vibration response. Three different loads 50/80/110 N-m, three different speeds 1500/2000/3000 rpm, and three different clearances, i.e., normal, 2 times and 4 times the normal clearance were simulated to examine the effect of wear on bearing forces. The magnitude of the squared envelope of the generated vibration signals though not affected by load, but was observed to rise significantly with increasing speed and clearance indicating the likelihood of augmented wear. In the present study, the simulation model was extended further to investigate the bearing wear behavior, resulting as a consequence of different operating conditions, to complement the vibration analysis. In the current simulation, the dynamics of the engine was established first, based on which the hydrodynamic journal bearing forces were evaluated by numerical solution of the Reynold’s equation. Also, the essential outputs of interest in this study, critical to determine wear rates are the tangential velocity and oil film thickness between the journal and bearing sleeve, which if not maintained appropriately, have a detrimental effect on the bearing performance. Archard’s wear prediction model was used in the simulation to calculate the wear rate of bearings with specific location information as all determinative parameters were obtained with reference to crank rotation. Oil film thickness obtained from the model was used as a criterion to determine if the lubrication is sufficient to prevent contact between the journal and bearing thus causing accelerated wear. A limiting value of 1 µm was used as the minimum oil film thickness needed to prevent contact. The increased wear rate with growing severity of operating conditions is analogous and comparable to the rise in amplitude of the squared envelope of the referenced vibration signals. Thus on one hand, the developed model demonstrated its capability to explain wear behavior and on the other hand it also helps to establish a correlation between wear based and vibration based analysis. Therefore, the model provides a cost-effective and quick approach to predict the impending wear in IC engine bearings under various operating conditions.

Keywords: condition monitoring, IC engine, journal bearings, vibration analysis, wear prediction

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Authors: B. Käfer, V. K. Bheemineni, H. Lammer, M. Kotnik, F. O. Riemelmoser

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Axial compression tests are performed on circular tubes made of Aluminum EN AW 6060 (AlMgSi0.5 alloy) in T66 state. All the received tubes have the uniform outer diameter of 40mm and thickness of 1.5mm. Two different lengths 100mm and 200mm are used in the analysis. After performing compression tests on the uniform tube, important crashworthy parameters like peak force, average force, crush efficiency and energy absorption are measured. The present paper has given importance to increase the percentage of crush efficiency without decreasing the value energy absorption of a tube, so a circumferential notch was introduced on the top section of the tube. The effects of position and cut-out lengths of a circumferential notch on the crush efficiency are well explained with relative deformation modes and force-displacement curves. The numerical simulations were carried on the software tool ANSYS/LS-DYNA. It is seen that the numerical results are reasonably good in agreement with the experimental results. 

Keywords: crash box, Notch triggering, energy absorption, FEM simulation

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Authors: Syed Hassan Tanvir Ramzi, Ubaidullah Ansari, Sana Manzoor, Namal Ilyas, Nabeel Ahmed

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Objective: To better understand the prevalence of neurological symptoms associated with COVID-19, several factors, such as age, gender, and comorbidity, are explored to create a more holistic understanding of the impact of COVID-19. Methods: After meeting inclusion and exclusion criteria, 111 patients admitted to Ibne Sina Hospital were recruited between October 2021 and February 2022. A descriptive statistical analysis was conducted to summarize patients' most often encountered signs and symptoms concerning the above parameters. Results: Out of 111 patients, a significant proportion of symptoms occurred in patients aged 40-60 years, with Dysgeusia being the most widespread (75.5%), followed by Encephalitis (45.9%), GBS (28.8%), Encephalopathy (18.9%), and Ischemic Stroke (6.3%). These were most prevalent in hypertensive individuals (46%) and Diabetes Mellitus (31%). In asthmatic individuals, they are the least prevalent (10.8%). Conclusion: Despite the predominance of neurological manifestations, the present scientific literature cannot demonstrate a definitive causal association between the symptoms and the virus. This study carefully ensures a link between age, gender, and comorbidity, along with the prevalence of neurological manifestations of COVID-19. For a comprehensive treatment plan, a holistic understanding of symptoms is critical.

Keywords: COVID 19, neurological association, GBS, Encephalitis

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Authors: Remember Samu, Kathy Kiema, Murat Fahrioglu

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This present study is aimed at minimizing the dependence on fossil fuels thus reducing greenhouse gas (GHG) emissions and also to curb for the rising energy demands in Kenya. In this analysis, 35 locations were each considered for their techno-economic potential of installation of a 10MW grid-connected PV plant. The sites are scattered across the country but are mostly concentrated in the eastern region and were selected based on their accessibility to the national grid and availability of their meteorological parameters from NASA Solar Energy Dataset. RETScreen software 4.0 version will be employed for the analysis in this present paper. The capacity factor, simple payback, equity payback, the net present value (NPV), annual life cycle savings, energy production cost, net annual greenhouse gas emission reduction and the equivalent barrels of crude oil not consumed are outlined. Energy accounting is performed and compared to the existing grid tariff for an effective feasibility argument of this 10MW grid-connected PV power system.

Keywords: photovoltaics, project viability analysis, PV module, renewable energy

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Authors: Oliver Echezona Ngwu

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The research was conducted in 2011 cropping season at the Teaching and Research farm of the Faculty of Agriculture and Natural Resources Management, Enugu State University of Science and Technology, Enugu, Nigeria to study the effect of organic and inorganic fertilizers on the growth and yield of physic Nut (Jatropha curcas). There were five treatments namely, control, (no application of treatment), NPK 20:10:10, NPK 15:15;15, poultry droppings and goat dung. The treatments were laid out in a Randomized complete Block Design (RCBD) with five replications. The total land area used was 228m2 (19x12m) while the plot size was 3mx2 (6m2). The growth parameters measured were plant height, number of leaves, and leaf area, index (LAI). The results obtained showed that there were significant differences at P=0.05 among the different treatments in 30, to and 90 DAP. Based on the results T4 (poultry droppings) had higher effect at P=0.05 at 30, 60, 90 DAP than the other treatments when compared and is hereby recommended as the best type of fertilizer for the optimum growth and production of physic Nut (Jatropha Curcas) in South Eastern Nigeria.

Keywords: organic, inorganic fertilizers, growth, yield, Jatropha curcas

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Authors: Javad Abdi, Azam Famil Khalili

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Modeling emotions have attracted much attention in recent years, both in cognitive psychology and design of artificial systems. However, it is a negative factor in decision-making; emotions have shown to be a strong faculty for making fast satisfying decisions. In this paper, we have adapted a computational model based on the limbic system in the mammalian brain for control engineering applications. Learning in this model based on Temporal Difference (TD) Learning, we applied the proposed controller (termed BELBIC) for a simple model of a submarine. The model was supposed to reach the desired depth underwater. Our results demonstrate excellent control action, disturbance handling, and system parameter robustness for TDBELBIC. The proposal method, regarding the present conditions, the system action in the part and the controlling aims, can control the system in a way that these objectives are attained in the least amount of time and the best way.

Keywords: artificial neural networks, temporal difference, brain emotional learning based intelligent controller, heating- ventilating and air conditioning

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Authors: Jee-Young Lee, Joaquim J. Ferreira, Hyeo-il Ma, José-Francisco Rocha, Beomseok Jeon

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The effective management of wearing-off is a key driver of medication changes for patients with Parkinson’s disease (PD) treated with levodopa (L-DOPA). While L-DOPA is well tolerated and efficacious, its clinical utility over time is often limited by the development of complications such as dyskinesia. Still, common first-line option includes adjusting the daily L-DOPA dose followed by adjunctive therapies usually counting for the L-DOPA equivalent daily dose (LEDD). The LEDD conversion formulae are a tool used to compare the equivalence of anti-PD medications. The aim of this work is to compare the effects of opicapone (OPC) 50 mg, a catechol-O-methyltransferase (COMT) inhibitor, and an additional 100 mg dose of L-DOPA in reducing the off time in PD patients with early motor fluctuations receiving different daily L-DOPA doses. OPC was found to be well tolerated and efficacious in advanced PD population. This work utilized patients' home diary data from a 4-week Phase 2 pharmacokinetics clinical study. The Korean ADOPTION study randomized (1:1) patients with PD and early motor fluctuations treated with up to 600 mg of L-DOPA given 3–4 times daily. The main endpoint was change from baseline in off time in the subgroup of patients receiving 300–400 mg/day L-DOPA at baseline plus OPC 50 mg and in the subgroup receiving >300 mg/day L-DOPA at baseline plus an additional dose of L-DOPA 100 mg. Of the 86 patients included in this subgroup analysis, 39 received OPC 50 mg and 47 L-DOPA 100 mg. At baseline, both L-DOPA total daily dose and LEDD were lower in the L-DOPA 300–400 mg/day plus OPC 50 mg group than in the L-DOPA >300 mg/day plus L-DOPA 100 mg. However, at Week 4, LEDD was similar between the two groups. The mean (±standard error) reduction in off time was approximately three-fold greater for the OPC 50 mg than for the L-DOPA 100 mg group, being -63.0 (14.6) minutes for patients treated with L-DOPA 300–400 mg/day plus OPC 50 mg, and -22.1 (9.3) minutes for those receiving L-DOPA >300 mg/day plus L-DOPA 100 mg. In conclusion, despite similar LEDD, OPC demonstrated a significantly greater reduction in off time when compared to an additional 100 mg L-DOPA dose. The effect of OPC appears to be LEDD independent, suggesting that caution should be exercised when employing LEDD to guide treatment decisions as this does not take into account the timing of each dose, onset, duration of therapeutic effect and individual responsiveness. Additionally, OPC could be used for keeping the L-DOPA dose as low as possible for as long as possible to avoid the development of motor complications which are a significant source of disability.

Keywords: opicapone, levodopa, pharmacokinetics, off-time

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Authors: HyeSuk Ri, HyonChol Kim, NamChol Yu

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The FTO thin films were deposited on 15 cm × 15 cm glass substrates by ultrasonic spray pyrolysis, and the influence of process parameters on the film properties was investigated. This paper is the first report on the design of a uniform nozzle and simulating the carrier gas flow characteristics in an ultrasonic spray pyrolysis process. The uniformity of FTO films was evaluated by surface resistivity. The structure, surface morphology and optical properties of FTO films were investigated using scanning electron microscopy, X-ray diffraction, and UV-Vis spectroscopy. The process conditions for film preparation were SnCl₄ concentration of 1.34 mol, NH₄F concentration of 0.08 mol, temperature of 500 °C, deposition time of 15 min, carrier gas flow rate of 3 m/s, distance between nozzle and substrate of 0.7 cm. The transmittance of the fabricated FTO films was 80%, the surface resistance showed a uniform behavior at 14-15Ω/cm² and the X-ray analysis showed a high orientation of SnO₂ crystals in the 200-plane. SEM analysis showed that the crystallite size was constant.

Keywords: nozzle design, FTO film, simulation, ultrasonic spray pyrolysis

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Authors: Swarali Hingse, Shraddha Digole, Uday Annapure

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The present study investigates the biotransformation of ferulic acid to vanillin by Pycnoporus cinnabarinus and its optimization using one-factor-at-a-time method as well as statistical approach. Effect of various physicochemical parameters and medium components was studied using one-factor-at-a-time method. Screening of the significant factors was carried out using L25 Taguchi orthogonal array and then these selected significant factors were further optimized using response surface methodology (RSM). Significant media components obtained using Taguchi L25 orthogonal array were glucose, KH2PO4 and yeast extract. Further, a Box Behnken design was used to investigate the interactive effects of the three most significant media components. The final medium obtained after optimization using RSM containing glucose (34.89 g/L), diammonium tartrate (1 g/L), yeast extract (1.47 g/L), MgSO4•7H2O (0.5 g/L), KH2PO4 (0.15 g/L), and CaCl2•2H2O (20 mg/L) resulted in amplification of vanillin production from 30.88 mg/L to 187.63 mg/L.

Keywords: ferulic acid, pycnoporus cinnabarinus, response surface methodology, vanillin

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Authors: Archana Thangavelu, Han-Ik Park, Young-Chul Park, Joon-Hong Park

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In this numerical study, we have proposed a method for evaluation of backward extrusion process of pressure vessel made up of steel. Demand for lighter and stiffer products have been increasing in the last years especially in automobile engineering. Through detailed finite element analysis, effective stress, strain and velocity profile have been obtained with optimal range. The process design of a forward and backward extrusion axe-symmetric part has been studied. Forging is mainly carried out because forged products are highly reliable and possess superior mechanical properties when compared to normal products. Performing computational simulations of 3D hot forging with various dimensions of billet and optimization of weight is carried out using Taguchi Orthogonal Array (OA) Optimization technique. The technique used in this study can be used for newly developed materials to investigate its forgeability for much complicated shapes in closed hot die forging process.

Keywords: backward extrusion, hot forging, optimization, finite element analysis, Taguchi method

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Authors: Yunusa Aliyu Hadejia

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Cholera is a gastrointestinal disease caused by a bacterium called Vibrio Cholerae which spread as a result of eating food or drinking water contaminated with feaces from an infected person. In this work we proposed and analyzed the impact of isolating infected people and give them therapeutic treatment, the specific objectives of the research was to formulate a mathematical model of cholera transmission incorporating treatment class, to make analysis on stability of equilibrium points of the model, positivity and boundedness was shown to ensure that the model has a biological meaning, the basic reproduction number was derived by next generation matrix approach. The result of stability analysis show that the Disease free equilibrium was both locally and globally asymptotically stable when R_0< 1 while endemic equilibrium has locally asymptotically stable when R_0> 1. Sensitivity analysis was perform to determine the contribution of each parameter to the basic reproduction number. Numerical simulation was carried out to show the impact of the model parameters using MAT Lab Software.

Keywords: mathematical model, treatment, stability, sensitivity

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Authors: A. A. Salisu, M. Y. Yakasai, K. M. Aujara

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Sisal leaves were subjected to enzymatic retting method to extract the sisal fibre. A portion of the fibre was pretreated with alkali (NaOH), and further treated with benzoyl chloride and silane treatment reagents. Both the treated and untreated Sisal fibre composites were used to fabricate the composite by hand lay-up technique using unsaturated polyester resin. Tensile, flexural, water absorption, density, thickness swelling and chemical resistant tests were conducted and evaluated on the composites. Results obtained for all the parameters showed an increase in the treated fibre compared to untreated fibre. FT-IR spectra results ascertained the inclusion of benzoyl and silane groups on the fibre surface. Scanning electron microscopy (SEM) result obtained showed variation in the morphology of the treated and untreated fibre. Chemical modification was found to improve adhesion of the fibre to the matrix, as well as physico-mechanical properties of the composites.

Keywords: chemical resistance, density test, polymer matrix sisal fibre, thickness swelling

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Authors: Irma Wani Othman

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The internationalization of higher education in Malaysia mainly focuses to place the implementation of the strategic, comprehensive and integrated range of stakeholders in order to highlight the visibility of Malaysia as a hub of academic excellence. While the concept of 'global citizenship' is used as a two-pronged strategy of aggressive marketing by universities which includes; (i) the involvement of the academic expatriates in stimulating international activities of higher education and (ii) an increase in international student enrollment capacity for the enculturation of science and the development of first class mentality. In this aspect, aspirations for a transnational social movement through global citizenship status to establish the identity of the university community without borders (borderless universities) - regardless of skin colour, thus rationalize and liberalize the universal principles of life and cultural traditions of a nation. The education system earlier referred by the spirit of nationalism is now progressing due to globalization, hence forming a system of higher education that is relevant and generated by the need of all time. However, debates arose when the involvement of global citizenship is said to threaten the ultimate university autonomy in determining the direction of academic affairs and governance of their human resources. Stemming from this debate, this study aims to explore the experience of 'global citizenship' that the academic expatriates and international students in shaping the university's strategic needs and interests which are in line with the transition of contemporary higher education. The objective of this study is to examine the acculturation experience of the global citizen in the form of transnational higher education system and suggest policy and policing IHE which refers directly to the experience of the global citizen. This study offers a detailed understanding of how the university communities assess their expatriation experience, thus becoming useful information for learning and transforming education. The findings also open an advanced perspective on the international mobility of human resources and the implications on the implementation of the policy of internationalization of higher education. The contribution of this study is expected to give new input, thus shift the focus of contextual literature for the internationalization of the education system. Instead of focusing on the purpose of generating income of a university, to a greater understanding of subjective experience in utilizing international human resources hence contributing to the prominent transnational character of higher education.

Keywords: internationalization, global citizens, Malaysia higher education, academic expatriate, international students

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Authors: Khalil Khanafer

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This study emphasizes on analyzing the effect of flow conditions and the geometric variation of the microcantilever’s bluff body on the microcantilever detection capabilities within a fluidic device using a finite element fluid-structure interaction model. Such parameters include inlet velocity, flow direction, and height of the microcantilever’s supporting system within the fluidic cell. The transport equations are solved using a finite element formulation based on the Galerkin method of weighted residuals. For a flexible microcantilever, a fully coupled fluid-structure interaction (FSI) analysis is utilized and the fluid domain is described by an Arbitrary-Lagrangian–Eulerian (ALE) formulation that is fully coupled to the structure domain. The results of this study showed a profound effect on the magnitude and direction of the inlet velocity and the height of the bluff body on the deflection of the microcantilever. The vibration characteristics were also investigated in this study. This work paves the road for researchers to design efficient microcantilevers that display least errors in the measurements.

Keywords: fluidic cell, FSI, microcantilever, flow direction

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Authors: Muuz Abraha Meshesha

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Illegal Migration, specifically Trafficking in person is one of the primary issues of the day affecting all states of the world with variation on the extent of the root causes and consequences that led people to migrate irregularly and the consequences it is costing on humanity. This paper intends to investigate the root causes and consequences of illegal migration in Ethiopia’s Tigray Regional state and come up with alternative intervening strategy. To come up with pertinent and robust research finding, this study employed mixed research approach involving qualitative and quantitative data in line with purposive and snow ball sampling selection technique. The study revealed that, though poverty is the most commonly sensed pushing factor for people to illegally migrate, the issue of psycho-social orientation and attitudinal immersion of the local community for illegal migration, both in thinking and action is the most pressing problem that urges serious intervention. Trafficking in persons and Illegal migration in general, is becoming the norm of the day in the study area that overtly reveal illegal migration is an issue beyond livelihood securing demand in practice. Basically, parties engaged in illegal migration and the accomplice with human traffickers these days in the study area are found to be more than urgency for food security and a need to escape from livelihood impoverishment. Therefore, this study come up with a new paradigm insight indicating that illegal migration is believed by the local community members as an optional path way of doing business in illegal way while the attitude of the community and officials authorized to regulate is being part of the channel or to the least tolerant of this grave global danger. The study also found that the effect of illegal migration is significantly manifested in long run than in short term periods. Therefore, a need for critical consideration on attitudinal based intervention and youth oriented and enforceable legal and policy framework accountability framework is required to face and control illegal migration by international, national, local stakeholders. Besides this, economy based development interventions that could engage and reorient the youth, as primary victims of trafficking, and expansion of large scale projects that can employ large number of youths at a time.

Keywords: human traficking, illegal migration, migration, tigray region

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Authors: Folajimi Oladimeji Shorunke

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Background: As of October 9, 2023, diphtheria has been noted to be re-emerging in four African countries: Algeria, Guinea, Niger, and Nigeria. 14,587 cases with a case fatality rate of 4.1% have been reported across these regions, with Nigeria alone responsible for over 90% of the cases. In Taraba State Nigeria, the index case of Diphtheria was reported on epidemic week 34, August 24, 2023 with 75 confirmed cases found 3 months after the index case and a case fatality of 1.3%. it described the distribution, trend and common symptoms found during the Outbreak. Methods: The Taraba State Diphtheria Outbreak line list on the Surveillance Outbreak Response Management & Analysis System (SORMAS) for all its 16 local government areas (LGAs) was analyzed using descriptive statistics (graphs, chats and maps) for the period between 24th August to 25th November 2023. Primary data was collected through the use of case investigation forms and variables like Age, gender, date of disease onset, LGA of residence, and symptoms exhibited were collected. Naso-pharyngeal and oro-pharyngeal samples were also collected for Laboratory confirmation. The most common diphtheria symptoms during the outbreak were also highlighted. Results: A total of 75 Diphtheria cases were diagnosed in 10 of the 16 LGAs in Taraba State between 24th August to 25th November 2023, 72% of the cases were female, with the age range 0-9 years having the highest proportion of 34 (45.3%), the number of positive diagnosis reduces with age among cases. The Northern part of the State had the highest proportion of cases, 68 (90.7%), with Ardo-Kola LGA having the highest 28 (29%). The remaining 9.2% of cases is shared among the middle belt and southern part of the State. The Epi-curve took the characteristic shape of a propagated infection with peaks at the 37th, 39th and 45th epidemic weeks. The most common symptoms found in cases were fever 71 (94.7%), pharyngitis 65( 86.7%), tonsillitis 60 (80%), and laryngitis 53 (71%). Conclusions: The number of confirmed cases of Diphtheria in Taraba State, Nigeria between 24th August to 25th November 2023 is 75. The condition is higher among females than male and mostly affected children between ages 0-9 with the northern part of the state most affected. The most common symptoms exhibited by cases include fever, pharyngitis, tonsillitis and laryngitis.

Keywords: diphtheria outbreak, taraba nigeria, descriptive epidemiology, trend

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Authors: Pernille K. Christiansen, Mette Maria Skjøth, Line Lorenzen, Eva Draborg, Christina Anne Vinter, Trine Kjær, Mette Juel Rothmann

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Background and aims: Overweight and obesity are an increasing challenge on a global level. In Denmark, more than one-third of all pregnant women are overweight or obese, and many women exceed the gestational weight gain recommendations from the Institute of Medicine. Being overweight or obese, is associated with a higher risk of adverse maternal and fetal outcomes, including gestational diabetes and childhood obesity. Thus, it is important to focus on the women’s lifestyles between their pregnancies to lower the risk of gestational weight retention in the long run. The objective of this study was to explorer what barriers and challenges postpartum women experience with respect to healthy lifestyles during the postpartum period and to access whether an Information Technology based intervention might be a supportive tool to assist and motivate postpartum women to a healthy lifestyle. Materials and methods: The method is inspired by participatory design. A systematic text condensation was applied to semi-structured focus groups. Five focus group interviews were carried out with a total of 17 postpartum women and two interviews with a total of six health professionals. Participants were recruited through the municipality in Svendborg, Denmark, and at Odense University Hospital in Odense, Denmark, during a four-month period in early 2018. Results: From the women’s perspective, better assistance is needed from the health professionals to obtain or maintain a healthy lifestyle. The women need tools that inform and help them understand and prioritise their own health-related risks, and to motivate them to plan and take care of their own health. As the women use Information Technology on a daily basis, the solution could be delivered through Information Technology. Finally, there is room for engaging the partner more in the communication related to the baby and family’s lifestyle. Conclusion: Postpartum women need tools that inform and motivate a healthy lifestyle postpartum. The tools should allow access to high-quality information from health care professionals, when the information is needed, and also allow engagement from the partner. Finally, Information Technology is a potential tool for delivering tools.

Keywords: information technology, lifestyle, overweight, postpartum

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Authors: Alex B. Cusick

Abstract:

The objective of this study is to improve upon the current ²³⁸PuO₂ fuel technology for space and defense applications. Modern RTGs (radioisotope thermoelectric generators) utilize the heat generated from the radioactive decay of ²³⁸Pu to create heat and electricity for long term and remote missions. Application of RTG technology is limited by the scarcity and expense of producing the isotope, as well as the power output which is limited to only a few hundred watts. The scarcity and expense make the efficient use of ²³⁸Pu absolutely necessary. By utilizing the decay of ²³⁸Pu, not only to produce heat directly but to also indirectly induce fission in ²³⁹Pu (which is already present within currently used fuel), it is possible to see large increases in temperature which allows for a more efficient conversion to electricity and a higher power-to-weight ratio. This concept can reduce the quantity of ²³⁸Pu necessary for these missions, potentially saving millions on investment, while yielding higher power output. Current work investigating radioisotope power systems have focused on improving efficiency of the thermoelectric components and replacing systems which produce heat by virtue of natural decay with fission reactors. The technical feasibility of utilizing (α,n) reactions to induce fission within current radioisotopic fuels has not been investigated in any appreciable detail, and our study aims to thoroughly investigate the performance of many such designs, develop those with highest capabilities, and facilitate experimental testing of these designs. In order to determine the specific design parameters that maximize power output and the efficient use of ²³⁸Pu for future RTG units, MCNP6 simulations have been used to characterize the effects of modifying fuel composition, geometry, and porosity, as well as introducing neutron moderating, reflecting, and shielding materials to the system. Although this project is currently in the preliminary stages, the final deliverables will include sophisticated designs and simulation models that define all characteristics of multiple novel RTG fuels, detailed enough to allow immediate fabrication and testing. Preliminary work has consisted of developing a benchmark model to accurately represent the ²³⁸PuO₂ pellets currently in use by NASA; this model utilizes the alpha transport capabilities of MCNP6 and agrees well with experimental data. In addition, several models have been developed by varying specific parameters to investigate their effect on (α,n) and (n,fi ssion) reaction rates. Current practices in fuel processing are to exchange out the small portion of naturally occurring ¹⁸O and ¹⁷O to limit (α,n) reactions and avoid unnecessary neutron production. However, we have shown that enriching the oxide in ¹⁸O introduces a sufficient (α,n) reaction rate to support significant fission rates. For example, subcritical fission rates above 10⁸ f/cm³-s are easily achievable in cylindrical ²³⁸PuO₂ fuel pellets with a ¹⁸O enrichment of 100%, given an increase in size and a ⁹Be clad. Many viable designs exist and our intent is to discuss current results and future endeavors on this project.

Keywords: radioisotope thermoelectric generators (RTG), Pu-238, subcritical reactors, (alpha, n) reactions

Procedia PDF Downloads 177

Authors: Lakshmi Sujeesh, Aaron Ramzeen, Ricky Ziming Guo, Abhishek Agrawal

Abstract:

Introduction: Range of motion (ROM) is often measured by physiotherapists using hand-held goniometer as part of mobility assessment for diagnosis. Due to the nature of hand-held goniometer measurement procedure, readings often tend to have some variations depending on the physical therapist taking the measurements (Riddle et al.). This study aims to validate computer vision software readings against goniometric measurements for quick and consistent ROM measurements to be taken by clinicians. The use of this computer vision software hopes to improve the future of musculoskeletal space with more efficient diagnosis from recording of patient’s ROM with minimal human error across different physical therapists. Methods: Using the hand-held long arm goniometer measurements as the “gold-standard”, healthy study participants (n = 20) were made to perform 4 exercises: Front elevation, Abduction, Internal Rotation, and External Rotation, using both arms. Assessment of active ROM using computer vision software at different angles set by goniometer for each exercise was done. Interclass Correlation Coefficient (ICC) using 2-way random effects model, Box-Whisker plots, and Root Mean Square error (RMSE) were used to find the degree of correlation and absolute error measured between set and recorded angles across the repeated trials by the same rater. Results: ICC (2,1) values for all 4 exercises are above 0.9, indicating excellent reliability. Lowest overall RMSE was for external rotation (5.67°) and highest for front elevation (8.00°). Box-whisker plots showed have showed that there is a potential zero error in the measurements done by the computer vision software for abduction, where absolute error for measurements taken at 0 degree are shifted away from the ideal 0 line, with its lowest recorded error being 8°. Conclusion: Our results indicate that the use of computer vision software is valid and reliable to use in clinical settings by physiotherapists for measuring shoulder ROM. Overall, computer vision helps improve accessibility to quality care provided for individual patients, with the ability to assess ROM for their condition at home throughout a full cycle of musculoskeletal care (American Academy of Orthopaedic Surgeons) without the need for a trained therapist.

Keywords: physiotherapy, frozen shoulder, joint range of motion, computer vision

Procedia PDF Downloads 112

Authors: Jatinder Kumar, Ajay Bansal

Abstract:

Simulation of a photocatalytic reactor helps in understanding the complex behavior of the photocatalytic degradation. Simulation also aids the designing and optimization of the photocatalytic reactor. Lack of simulation strategies is a huge hindrance in the commercialization of the photocatalytic technology. With the increased performance of computational resources, and development of simulation software, computational fluid dynamics (CFD) is becoming an affordable engineering tool to simulate and optimize reactor designs. In the present paper, a CFD (Computational fluid dynamics) model for simulating the performance of an immobilized-titanium dioxide based annular photocatalytic reactor was developed. The computational model integrates hydrodynamics, species mass transport, and chemical reaction kinetics using a commercial CFD code Fluent 6.3.26. The CFD model was based on the intrinsic kinetic parameters determined experimentally in a perfectly mixed batch reactor. Rhodamine B, a complex organic compound, was selected as a test pollutant for photocatalytic degradation. It was observed that CFD could become a valuable tool to understand and improve the photocatalytic systems.

Keywords: simulation, computational fluid dynamics (CFD), annular photocatalytic reactor, titanium dioxide

Procedia PDF Downloads 589

Authors: Giacomo Barbieri

Abstract:

In soilless culture, the management of the nutrient solution is the most important aspect for crop growing. Fertigation dose, frequency and nutrient concentration must be planned with the objective of reaching an optimal crop growth by limiting the utilized resources and the associated costs. The definition of efficient fertigation strategies is a complex problem since fertigation requirements vary on the basis of different factors, and crops are sensitive to small variations on fertigation parameters. To the best of author knowledge, a small-scale test bench that is flexible for both nutrient solution preparation and precise irrigation is currently missing, limiting the investigations in standard practices for soilless culture. Starting from the analysis of the state of the art, this paper proposes a small-scale system that is potentially able to concurrently test different fertigation strategies. The system will be designed and implemented throughout a three year project started on August 2018. However, due to the importance of the topic within current challenges as food security and climate change, this work is spread considering that may inspire other universities and organizations.

Keywords: soilless culture, fertigation, test bench, small-scale, automation

Procedia PDF Downloads 178

Authors: Alina Beraudi, Simona Catalani, Dalila De Pasquale, Eva Bianconi, Umberto Santoro, Susanna Stea, Pietro Apostoli

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Recently the European Community, in line with the international scientific community such as with the Consensus Statement, has determined to stop the use of metal-on-metal big head stemmed hip prosthesis. Among the factors accounted as responsible for the high failure rates of these hip implants are the release and accumulation of metal ions. Many studies have correlated the presence of these ions, besides other factors, with the induction of oxidative stress response. In our study on 12 subjects, we observed the patient specific capability to eliminate metal ions after revision surgery. While for cobalt all the patients were able to completely excrete cobalt ions within 5-7 months after metal-on-metal bearing removal, for chromium ions it didn’t happen. If on the one hand the toxicokinetic differences between the two types of ions are confirmed by toxicological and occupational studies, on the other hand, this peculiar way of exposition represents a novel and important point of view. Thus, two different approaches were performed to better understand the subject specific capability to transport metal ions (albumin study) and to manage the response to them (heme-oxygenase-1 study): - a mutational screening of ALBUMIN gene was conducted in 30 MoM prosthetic patients resulting in the absence of nucleotidic changes compared with the ALB reference sequence. To this study was also added the analysis of expression of modified albumin protein; - a gene and protein expression study on 44 patients of heme-oxygenase-1, that is one of the most important antioxidant enzyme induced by metallic ions, was performed. This study resulted in no statistically significant differences in the expression of the gene and protein heme-oxygenase-1 between prosthetic and non-prosthetic patients, as well as between patients with high and low ions levels. Our results show that the protein studied (albumin and heme-oxygenase-1) seem to be not involved in determining chromium and cobalt ions level. On the other hand, achromium and cobalt elimination rates are different, but similar in all patients analyzed, suggesting that this process could be not patient-related. We support the importance of researching more about ions transport within the organism once released by hip prosthesis, about the chemical species involved, the districts where they are contained and the mechanisms of elimination, not excluding the existence of a subjective susceptibility to these metals ions.

Keywords: chromium, cobalt, hip prosthesis, individual susceptibility

Procedia PDF Downloads 390

Authors: M. Sajjadnejad, H. Karimi Abadeh

Abstract:

In this research, zinc coatings were fabricated by electroplating process in a sulfate solution under direct and pulse current conditions. In direct and pulse current conditions, effect of maximum current was investigated on the coating properties. Also a comparison was made between the obtained coatings under direct and pulse current. Morphology of the coatings was investigated by scanning electron microscopy (SEM). Corrosion behavior of the coatings was investigated by potentiodynamic polarization test. In pulse current conditions, the effect of pulse frequency and duty cycle was also studied. The effect of these conditions and parameters were also investigated on morphology and corrosion behavior. All of DC plated coatings are showing a distinct passivation area in -1 to -0.4 V range. Pulsed current coatings possessed a higher corrosion resistance. The results showed that current density is the most important factor regarding the fabrication process. Furthermore, a rise in duty cycle deteriorated corrosion resistance of coatings. Pulsed plated coatings performed almost 10 times better than DC plated coatings.

Keywords: corrosion, duty cycle, pulsed current, zinc

Procedia PDF Downloads 126

Authors: R. Ziaie Moayed, A. Mahigir

Abstract:

Stone column technique has been successfully employed to improve the load-settlement characteristics of foundations. A series of finite element numerical analyses of harmonic dynamic loading have been conducted on strengthened raft footing to study the effects of single and group stone columns on settlement of circular footings. The settlement of circular raft footing that improved by single and group of stone columns are studied under harmonic dynamic loading. This loading is caused by heavy machinery foundations. A detailed numerical investigation on behavior of single column and group of stone columns is carried out by varying parameters like weight of machinery, loading frequency and period. The result implies that presence of single and group of stone columns enhanced dynamic behavior of the footing so that the maximum and residual settlement of footing significantly decreased. 

Keywords: finite element analysis, harmonic loading, settlement, stone column

Procedia PDF Downloads 374