Search results for: creeping control strategy

Authors: Adeleye O. O., T. M. Obuotor, A. O. Kolawole, I. O. Opowoye, M. I. Olasoju, L. T. Egbeyale, R. A. Ajadi

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This study investigated the effect of Lagenaria breviflora on broiler poultry birds, including its effect on the microbial count of the poultry droppings. A total of 240-day-old broiler chicks were randomly assigned to six groups, with four replicates per group. The first group was the control, while the other four groups were fed water containing 300g/L and 500g/L concentrations of Lagenaria breviflora twice and thrice daily. The microbial load was determined using the plate count method. The results showed that the administration of Lagenaria breviflora in the water of broiler birds significantly improved their growth performance with an average weight gain range of 1.845g - 2.241g. Mortality rate was at 0%. The study also found that Lagenaria breviflora had a significant effect on the microbial count of the poultry droppings with colony count values from 3.5 x 10-7 - 9.9 x10-7CFU/ml, The total coliforms (Escherichia coli, and Salmonella sp.) was obtained as 1 x 10 -5CFU/ml. The reduction in microbial counts of the poultry droppings could be attributed to the antimicrobial properties of Lagenaria breviflora, which contain phytochemicals reported to possess antimicrobial activity. Therefore, the inclusion of Lagenaria breviflora in the diets of broiler poultry could be an effective strategy for improving growth performance and immune function and reducing the microbial load of poultry droppings, which can help to mitigate the risk of disease transmission to humans and other animals.

Keywords: gut microbes, bacterial count, lagenaria breviflora, coliforms

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Authors: Tripta Dixit, Smita Sahu, William Selvamurthy, Sadhana Srivastava

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India is battling with the issues of accessibility, affordability and availability of quality health to the masses. Indian medical heritage which dated back to 3000 BC unveils the rich knowledge pool which has undergone a perceptible change over years, such as eradication of many communicable diseases, increasing individual awareness of quality health and import driven medical device market etc. Despite a slew of initiatives the holistic slogan of ‘health for all’ remains elusive and a concern for the nation. The 21st-century projects a myriad of challenges like cultural diversity, large population, demographic dividend and geographical segmentation leading to varied needs of people as per their regional conditions of climate, disease prevalence, nutrition and sanitation. But these challenges are also opportunities for the development of indigenous, low cost and accessible technologies to tackle them. This requires reinforcing the potential of indigenous technologies in coordination with prevailing health issues in various regions of country. This paper emphasis on the strategy for exploring the indigenous technologies with entrusted up-scaling to meet the diverse needs of the people. This review proposes to adopt technology transfer as a strategy to establish a vibrant ecosystem for identifying and up-scaling the indigenous medical technologies with diligent hand-holding for public health.

Keywords: health, indigenous, medical technology, technology transfer

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Authors: Aziz Sezgin

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We consider the problem of stabilization of an unstable heat equation in a 2-D, 3-D and generally n-D domain by deriving a generalized backstepping boundary control design methodology. To stabilize the systems, we design boundary backstepping controllers inspired by the 1-D unstable heat equation stabilization procedure. We assume that one side of the boundary is hinged and the other side is controlled for each direction of the domain. Thus, controllers act on two boundaries for 2-D domain, three boundaries for 3-D domain and ”n” boundaries for n-D domain. The main idea of the design is to derive ”n” controllers for each of the dimensions by using ”n” kernel functions. Thus, we obtain ”n” controllers for the ”n” dimensional case. We use a transformation to change the system into an exponentially stable ”n” dimensional heat equation. The transformation used in this paper is a generalized Volterra/Fredholm type with ”n” kernel functions for n-D domain instead of the one kernel function of 1-D design.

Keywords: backstepping, boundary control, 2-D, 3-D, n-D heat equation, distributed parameter systems

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Authors: J. Yan, B. Pieper, B. Bucsky, B. Nasseri, S. Klotz, H. H. Sievers, S. Mohamed

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Cryoablation is evermore applied for interventional treatment of paroxysmal (PAAF) or persistent atrial fibrillation (PEAF). In the cardiac surgery, this procedure is often combined with coronary arterial bypass graft (CABG) and valve operations. Three different methods are feasible in this sense in respect to practicing extents and mechanisms such as lone left atrial cryoablation, Cox-Maze IV and III in our heart center. 415 patients (68 ± 0.8ys, male 68.2%) with predisposed atrial fibrillation who initially required either coronary or valve operations were enrolled and divided into 3 matched groups according to deployed procedures: CryoLA-group (cryoablation of lone left atrium, n=94); Cox-Maze-IV-group (n=93) and Cox-Maze-III-group (n=8). All patients additionally received closure of the left atrial appendage (LAA) and regularly underwent three-year ambulant follow-up assessments (3, 6, 9, 12, 18, 24, 30 and 36 months). Burdens of atrial fibrillation were assessed directly by means of cardiac monitor (Reveal XT, Medtronic) or of 3-day Holter electrocardiogram. Herewith, attacks frequencies of AF and their circadian patterns were systemically analyzed. Furthermore, anticoagulants and regular rate-/rhythm-controlling medications were evaluated and listed in terms of anti-rate and anti-rhythm regimens. Concerning PAAF treatment, Cox Maze IV procedure provided therapeutically acceptable effect as lone left atrium (LA) cryoablation did (5.25 ± 5.25% vs. 10.39 ± 9.96% AF-burden, p > 0.05). Interestingly, Cox Maze III method presented a better short-term effect in the PEAF therapy in comparison to lone cryoablation of LA and Cox Maze IV (0.25 ± 0.23% vs. 15.31 ± 5.99% and 9.10 ± 3.73% AF-burden within the first year, p < 0.05). But this therapeutic advantage went lost during ongoing follow-ups (26.65 ± 24.50% vs. 8.33 ± 8.06% and 15.73 ± 5.88% in 3rd follow-up year). In this way, lone LA-cryoablation established its antiarrhythmic efficacy and 69.5% patients were released from the Vit-K-antagonists, while Cox Maze IV liberated 67.2% patients from continuous anticoagulant medication. The AF-recurrences mostly performed such attacks property as less than 60min duration for all 3 procedures (p > 0.05). In the sense of the circadian distribution of the recurrence attacks, weighted by ongoing follow-ups, lone LA cryoablation achieved and stabilized the antiarrhythmic effects over time, which was especially observed in the treatment of PEAF, while Cox Maze IV and III had their antiarrhythmic effects weakened progressively. This phenomenon was likewise evaluable in the therapy of circadian rhythm of reverting AF-attacks. Furthermore, the strategy of rate control was much more often applied to support and maintain therapeutic successes obtained than the one of rhythm control. Derived from experiences in our heart center, lone LA cryoablation presented equivalent effects in the treatment of AF in comparison to Cox Maze IV and III procedures. These therapeutic successes were especially investigable in the patients suffering from persistent AF (PEAF). Additional supportive strategies such as rate control regime should be initialized and implemented to improve the therapeutic effects of the cryoablations according to appropriate criteria.

Keywords: AF-burden, atrial fibrillation, cardiac monitor, COX MAZE, cryoablation, Holter, LAA

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Authors: Louay Safi

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The notion of secular society that evolved over the last two centuries was initially intended to free the public sphere from religious imposition, before it assumed the form a comprehensive ideology whose aim is to prevent any overt religious expression from the public space. The negative view of religious expression, and the desire by political elites to purge the public space from all forms of religious expressions were first experienced in the Middle East in the last decades of the twentieth century in relation to Islam, before it manifests itself in the twentieth century Europe. Arab regimes were encouraged by European democracies to marginalize all forms of religious expressions in the public as part of the secularization process that was deemed necessary for modernization and progress. The prohibition of Islamic symbols and outlawing the headscarf was first undertaken to Middle Eastern republics, such as Turkey in 1930s and Syria in 1970s, before it is implemented recently in France. Secularization has been perceived by European powers as the central aspect of social and political liberalization, and was given priority over democratization and human rights, so much so that European elites were willing to entrust the task of nurturing liberal democracy to Arab autocrats and dictators. Not only did the strategy of empowering autocratic regimes to effect liberal democratic culture failed, but it contributed to the rise of Islamist extremism and produced failed states in Syria and Iraq that undermine both national and global peace and stability. The paper adopts the distinction made by John Rawls between political and comprehensive liberalism to argue that the modernization via secularization in Muslim societies is counterproductive and has subverted early successful efforts at democratization and reform in the Middle East. Using case studies that illustrate the role of the secularization strategy in Syria, Iran, and Egypt in undermining democratic and reformist movements in those countries, the paper calls for adopting a different approach rooted in liberal and democratic values rather than cultural practices and lifestyle. The paper shows that Islamic values as articulated by reform movements support a democratic and pluralist political order, and emphasizes the need to legitimize and support social forces that advocate democracy and human rights. Such an alternative strategy allows for internal competition among social groups for popular support, and therefore enhances the chances that those with inclusive and forward-looking political principles and policies would create a democratic and pluralist political order more conducive to meaningful national and global cooperation, and respectful of human dignity.

Keywords: democracy, Islamic values, political liberalism, secularization

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Authors: Hasmithaa Neha, Atul Kumar Patidar, Girish Ch Kothyari

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The northward convergence of the Indian plate has a dominating influence over the structural and geomorphic development of the Himalayan region. The highly deformed and complex stratigraphy in the area arises from a confluence of exogenic and endogenetic geological processes. This region frequently experiences natural hazards such as debris flows, flash floods, avalanches, landslides, and earthquakes due to its harsh and steep topography and fragile rock formations. Therefore, remote sensing technique-based examination and real-time monitoring of tectonically sensitive regions may provide crucial early warnings and invaluable data for effective hazard mitigation strategies. In order to identify unusual changes in the river gradients, the current study demonstrates a spatial quantitative geomorphic analysis of the upper Alaknanda River basin, Uttarakhand Himalaya, India, using gradient length anomaly analysis (GLAA). This basin is highly vulnerable to ground creeping and landslides due to the presence of active faults/thrusts, toe-cutting of slopes for road widening, development of heavy engineering projects on the highly sheared bedrock, and periodic earthquakes. The intersecting joint sets developed in the bedrocks have formed wedges that have facilitated the recurrence of several landslides. The main objective of current research is to identify abnormal gradient lengths, indicating potential landslide-prone zones. High-resolution digital elevation data and geospatial techniques are used to perform this analysis. The results of GLAA are corroborated with the historical landslide events and ultimately used for the generation of landslide susceptibility maps of the current study area. The preliminary results indicate that approximately 3.97% of the basin is stable, while about 8.54% is classified as moderately stable and suitable for human habitation. However, roughly 19.89% fall within the zone of moderate vulnerability, 38.06% are classified as vulnerable, and 29% fall within the highly vulnerable zones, posing risks for geohazards, including landslides, glacial avalanches, and earthquakes. This research provides valuable insights into the spatial distribution of landslide-prone areas. It offers a basis for implementing proactive measures for landslide risk reduction, including land-use planning, early warning systems, and infrastructure development techniques.

Keywords: landslide vulnerability, geohazard, GLA, upper Alaknanda Basin, Uttarakhand Himalaya

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Authors: Herlandson C. Moura, Jorge H. Bidinotto, Eduardo M. Belo

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The present work proposes the development of an adaptive control system which enables the suppression of Pilot Induced Oscillations (PIO) in Digital Fly-By-Wire (DFBW) aircrafts. The proposed system consists of a Modified Model Reference Adaptive Control (M-MRAC) integrated with the Gain Scheduling technique. The PIO oscillations are detected using a Real Time Oscillation Verifier (ROVER) algorithm, which then enables the system to switch between two reference models; one in PIO condition, with low proneness to the phenomenon and another one in normal condition, with high (or medium) proneness. The reference models are defined in a closed loop condition using the Linear Quadratic Regulator (LQR) control methodology for Multiple-Input-Multiple-Output (MIMO) systems. The implemented algorithms are simulated in software implementations with state space models and commercial flight simulators as the controlled elements and with pilot dynamics models. A sequence of pitch angles is considered as the reference signal, named as Synthetic Task (Syntask), which must be tracked by the pilot models. The initial outcomes show that the proposed system can detect and suppress (or mitigate) the PIO oscillations in real time before it reaches high amplitudes.

Keywords: adaptive control, digital Fly-By-Wire, oscillations suppression, PIO

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Authors: Fatma H. Galal, Alaaeddeen M. Seufi

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Due to the increasing usage of mobile phone, experiments were designed to investigate ‎the effect of acute dose exposure on the mosquito life cycle. 50 tubes (5 ml size) ‎containing 3 ml water and a first instar larva of the mosquito, Culex univittatus were put ‎between two mobile cell phones switched on talking mode for 4 continuous hours. A ‎control group of tubes (unexposed to radiation) were used. Larval and pupal durations ‎were calculated. Furthermore, adult emergence and sex ratio were observed for both ‎treated and control larvae. Results indicated that the employed dose of radiation reduced ‎total larval duration to about half the value of control. 1st, 2nd, 3rd and 4th larval ‎durations were reduced significantly by mobile radiation when compared to controls. ‎Meanwhile pupal duration was elongated significantly by mobile radiation when ‎compared to control. Sex ratio was significantly shifted in favor of females in the case of ‎radiated mosquitoes. Successful adult emergence was decreased significantly in the case ‎of radiated insects when compared to controls. Molecular studies to investigate the ‎effects of mobile radiation on insects and other model organisms are going on.‎

Keywords: mosquito, mobilr radiation, larval and pupal durations, sex ratio

Procedia PDF Downloads 182

Authors: Amer Rghei

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The Sahara region potentially is one of the most attractive heritage areas in the world. Yet presently, the heritage of the Sahara is currently facing serious planning challenges of underdeveloped and neglected economic and physical potentials. Deterioration of heritage resources has been observed by the author during his several field tours for historic sites has discovered special heritage values such as in Ghadames which combines historic oasis, natural environment along with its exceptional urban fabric and architectural character. Despite the richness of Ghadames with historic significance, it is found that at the present time, Ghadames city, the UNESCO World Heritage site, is facing serious challenges including the abandonment by its tenants and inclusive negligence by its officials. The author believes that Ghadames can illustrate an excellent heritage example in North Africa with cultural pride and socio-economic opportunities that can contribute to overall economic development in the Sahara region. However, the paper deals with the case of Ghadames ‘The World Heritage Site’ in Libya and discusses the current challenges and possible planning for its heritage conservation strategy. The momentous resources in Ghadames with their historical, environmental, economic, social, cultural, and aesthetic values would benefit from a careful heritage planning and management program for its significant values. In this paper an attempt is made to investigate this issue seriously towards building a model of a strategy for heritage conservation planning for Ghadames is proposed.

Keywords: Ghadames, Oasis architecture, Sahara region, heritage environment

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Authors: Corentin Jankowiak, Aggelos Zacharopoulos, Caterina Brandoni

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In a context of increasing stress put on the electricity network by the decarbonization of many sectors, energy storage is likely to be the key mitigating element, by acting as a buffer between production and demand. In particular, the highest potential for storage is when connected closer to the loads. Yet, low voltage storage struggles to penetrate the market at a large scale due to the novelty and complexity of the solution, and the competitive advantage of fossil fuel-based technologies regarding regulations. Strong and reliable numerical simulations are required to show the benefits of storage located near loads and promote its development. The present study was restrained from excluding aggregated control of storage: it is assumed that the storage units operate independently to one another without exchanging information – as is currently mostly the case. A computationally light battery model is presented in detail and validated by direct comparison with a domestic battery operating in real conditions. This model is then used to develop Peak-Shaving (PS) control strategies as it is the decentralized service from which beneficial impacts are most likely to emerge. The aggregation of flatter, peak- shaved consumption profiles is likely to lead to flatter and arbitraged profile at higher voltage layers. Furthermore, voltage fluctuations can be expected to decrease if spikes of individual consumption are reduced. The crucial part to achieve PS lies in the charging pattern: peaks depend on the switching on and off of appliances in the dwelling by the occupants and are therefore impossible to predict accurately. A performant PS strategy must, therefore, include a smart charge recovery algorithm that can ensure enough energy is present in the battery in case it is needed without generating new peaks by charging the unit. Three categories of PS algorithms are introduced in detail. First, using a constant threshold or power rate for charge recovery, followed by algorithms using the State Of Charge (SOC) as a decision variable. Finally, using a load forecast – of which the impact of the accuracy is discussed – to generate PS. A performance metrics was defined in order to quantitatively evaluate their operating regarding peak reduction, total energy consumption, and self-consumption of domestic photovoltaic generation. The algorithms were tested on load profiles with a 1-minute granularity over a 1-year period, and their performance was assessed regarding these metrics. The results show that constant charging threshold or power are far from optimal: a certain value is not likely to fit the variability of a residential profile. As could be expected, forecast-based algorithms show the highest performance. However, these depend on the accuracy of the forecast. On the other hand, SOC based algorithms also present satisfying performance, making them a strong alternative when the reliable forecast is not available.

Keywords: decentralised control, domestic integrated batteries, electricity network performance, peak-shaving algorithm

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Authors: Abdulrahman Abdulrahman

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Critical depth meters, such as abroad crested weir, Venture Flume and combined control flume are standard devices for measuring flow in open channels. The discharge relation for these devices cannot be solved directly, but it needs iteration process to account for the approach velocity head. In this paper, analytical solution was developed to calculate the discharge in a combined critical depth-meter namely, a hump combined with lateral contraction in rectangular channel with subcritical approach flow including energy losses. Also analytical formulae were derived for approach velocity head coefficient for different types of critical depth meters. The solution was derived by solving a standard cubic equation considering energy loss on the base of trigonometric identity. The advantage of this technique is to avoid iteration process adopted in measuring flow by these devices. Numerical examples are chosen for demonstration of the proposed solution.

Keywords: broad crested weir, combined control meter, control structures, critical flow, discharge measurement, flow control, hydraulic engineering, hydraulic structures, open channel flow

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Authors: Emily Simango, T. Chitura

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Background: Bovine brucellosis is among the most neglected zoonotic diseases in developing countries, where it is endemic and a growing challenge to public health. The development of cost-effective control measures for the disease can only be affirmed by the knowledge of the disease epidemiology and the ability to define its risk profiles. The aim of the study was to document the trend of bovine brucellosis and the control measures adopted following reported cases during the period 2014 to 2019 in South Africa. Methods: Data on confirmed cases of bovine brucellosis was retrieved from the website of the World Organisation of Animal Health (WOAH). Data was analysed using the Statistical Package for Social Sciences (IBM SPSS, 2022) version 29.0. Descriptive analysis (frequencies and percentages) and the Analysis of variance (ANOVA) were utilized for statistical significance (p<0.05). Results: The data retrieved in our study revealed an overall average bovine brucellosis prevalence of 8.48. There were statistically significant differences in bovine brucellosis prevalence across the provinces for the years 2016 and 2019 (p≥0.05), with the Eastern Cape Province having the highest prevalence in both instances. Documented control measures for the disease were limited to killing and disposal of disease cases as well as vaccination of susceptible animals. Conclusion: Bovine brucellosis is real in South Africa, with the risk profiles differing across the provinces. Information on brucellosis control measures in South Africa, as reported to the WOAH, is not comprehensive.

Keywords: zoonotic, endemic, Eastern Cape province, vaccination

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Authors: Roohallah Yousefi

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Introduction: In beta-thalassemia, an imbalance in the production of beta subunits of hemoglobin leads to the oxidation and deposition of excess alpha-globin chains at the cell membrane, resulting in the hemolysis of erythrocytes and a disorder of erythropoiesis. Antioxidants, such as curcumin, may promote this progression. This study aims to investigate the antioxidant effect of curcumin on hemolysate samples from patients with beta-thalassemia. Materials and methods: Pure curcumin was extracted and purified for use in studying its effect on the visual light absorbance of hemoglobin in hemolysate samples from beta-thalassemia patients compared to control samples. Changes in light absorbance at 540 and 700 nm wavelengths during exposure to curcumin were analyzed to examine the shift from oxyhemoglobin to deoxyhemoglobin. Results: Curcumin was found to dissolve rapidly and to a high degree in ethanol at 1 mg/ml, but did not dissolve in distilled water at the same concentration. The curcumin addition to the hemolysate sample of a patient with beta-thalassemia resulted in a decrease in the light absorbance of the sample at 540 nm wavelength, with minimal changes observed in the control sample. Conclusion: Curcumin deoxygenated the hemolysate samples from both the patient and control, causing hemoglobin precipitation to occur slowly. The study suggests a greater potential role for curcumin in deoxygenating hemoglobin in the hemolysate samples of beta-thalassemia patients compared to those of the normal control.

Keywords: beta-thalassemia, hemoglobin, curcumin, alpha-globin

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Authors: Mohammad Mashud, S. M. Nahid Hasan

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The aim of the research work is to modify the NACA 4215 airfoil with flap and rotary cylinder at the leading edge of the airfoil and experimentally study the static pressure distribution over the airfoil completed with flap and leading-edge vortex generator. In this research, NACA 4215 wing model has been constructed by generating the profile geometry using the standard equations and design software such as AutoCAD and SolidWorks. To perform the experiment, three wooden models are prepared and tested in subsonic wind tunnel. The experiments were carried out in various angles of attack. Flap angle and momentum injection rate are changed to observe the characteristics of pressure distribution. In this research, a new concept of flow separation control mechanism has been introduced to improve the aerodynamic characteristics of airfoil. Control of flow separation over airfoil which experiences a vortex generator (rotating cylinder) at the leading edge of airfoil is experimentally simulated under the effects of momentum injection. The experimental results show that the flow separation control is possible by the proposed mechanism, and benefits can be achieved by momentum injection technique. The wing performance is significantly improved due to control of flow separation by momentum injection method.

Keywords: airfoil, momentum injection, flap, pressure distribution

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Authors: K. Kouzi

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In order to have stable and high performance of direct torque and flux control (DTFC) of double star induction motor drive (DSIM), proper on-line adaptation of the stator resistance is very important. This is inevitably due to the variation of the stator resistance during operating conditions, which introduces error in estimated flux position and the magnitude of the stator flux. Error in the estimated stator flux deteriorates the performance of the DTFC drive. Also, the effect of error in estimation is very important especially at low speed. Due to this, our aim is to overcome the sensitivity of the DTFC to the stator resistance variation by proposing on-line fuzzy estimation stator resistance. The fuzzy estimation method is based on an on-line stator resistance correction through the variations of the stator current estimation error and its variations. The fuzzy logic controller gives the future stator resistance increment at the output. The main advantage of the suggested algorithm control is to avoid the drive instability that may occur in certain situations and ensure the tracking of the actual stator resistance. The validity of the technique and the improvement of the whole system performance are proved by the results.

Keywords: direct torque control, dual stator induction motor, Fuzzy Logic estimation, stator resistance adaptation

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Authors: Sisi Xia, Dezhuan Tao

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Urban Double Reform is an effective means to improve the quality of ecological space, based on improving the living environment and urban functions and promoting the organic integration of the city and nature. This paper takes the design of Qinyang Wetland Park in Jiaozuo, Henan Province, as an example, attempting to closely link the ecological restoration of wetland with the urban culture and to extend the urban spirit of the ancient county of Qinyang while purifying the ecological water system. This design uses ecological technology to repair underwater forests and underwater turf, rapidly improving the quality of urban water without biological side effects. The ecological grass slope is used to create multiple bank forms, combining with a number of hydrophilic platforms to provide a good view of the public. Through the placement of ecological education bases, urban cultural exhibition halls, and other means, the cultural value of wetland parks will be enhanced, and the citizens will return to nature and experience the ecology and appreciate the charm of urban culture in the ecological space. Repair the ecosystem, sculpt the urban culture, let the public return to nature, experience the ecology, and experience the charm of urban culture in the ecological space.

Keywords: urban double reform, ecological space, improvement strategy, wetland park design

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Authors: Benguerine Zohra, Merzak Siham, Pr. Chelghoum

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Introduction: The widespread production and consumption of antibiotics have raised significant concerns due to various adverse effects and the development of bacterial resistance. This increasing resistance to currently available antibiotics necessitates the search for new antibacterial agents. One alternative strategy to combat antibiotic-resistant bacteria is the use of natural antimicrobial substances such as plant extracts. This study aims to provide an overview of the antibacterial effects of Salvia officinalis (sage), a plant native to the Middle East and Mediterranean regions. Materials and Methods: This review was conducted by searching studies in databases such as PubMed, Scopus, JSTOR, and SpringerLink. The search terms were “Salvia officinalis L.” and “antibacterial effects.” Only studies that met our inclusion criteria (in English, focusing on the antibacterial effects of Salvia officinalis L., and primarily dated from 2012 to 2023) were considered for further review. Results and Discussion: The initial search strategy identified approximately 78 references, of which only 13 articles were included in this review. The synthesis of these articles revealed that multiple data sources confirm the antimicrobial effects of S. officinalis. Its essential oil and alcoholic extract exhibit strong bactericidal and bacteriostatic effects against both Gram-positive and Gram-negative bacteria. Conclusion: The significant value of the extract, oil, and leaves of S. officinalis demands further studies on other useful and unknown properties of this multipurpose plant.

Keywords: salvia officinalis, literature review, antibacterial., botany

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Authors: R. R. Mankbadi

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There are several technologically-important flow situations in which there is a need to control the outcome of the fluid flow. This could include flow separation, drag, noise, as well as particulate separations, to list only a few. One possible approach is the passive control, in which the design geometry is changed. An alternative approach is the Active Flow Control (AFC) technology in which an actuator is embedded in the flow field to change the outcome. Examples of AFC are pulsed jets, synthetic jets, plasma actuators, heating, and cooling, etc. In this work will present an overview of the development of this field. Some examples will include Airfoil Noise Suppression: Large-Eddy Simulations (LES) is used to simulate the effect of synthetic jet actuator on controlling the far field sound of a transitional airfoil. The results show considerable suppression of the noise if the synthetic jet is operated at frequencies. Mixing Enhancement and suppression: Results will be presented to show that imposing acoustic excitations at the nozzle exit can lead to enhancement or reduction of the jet plume mixing. In vertical takeoff of Aircrafts or in Space Launch, we will present results on the effects of water injection on reducing noise, and on protecting the structure and payload from fatigue damage. Other applications will include airfoil-gust interaction and propulsion systems optimizations.

Keywords: aeroacoustics, flow control, aerodynamics, large eddy simulations

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Authors: Johanna Schumacher, Toribio F. Otero, Victor H. Pascual

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Bending dual sensing-actuators based on electroactive polymers are faradaic motors meaning the consumed charge determines the actuator’s tip position. During actuation, consumed charges during oxidation and reduction result in different tip positions showing dynamic hysteresis effects with errors up to 25%. For a precise position control of these actuators, the characterization of the hysteresis effect due to irreversible reactions is crucial. Here, the investigation and modelling of dynamic hysteresis effects of polypyrrole-dodezylbenzenesulfonate (PPyDBS) actuators under ambient working conditions are presented. The hysteresis effect is studied for charge consumption at different frequencies and a rate-dependent hysteresis model is derived. The hysteresis model is implemented as closed loop system and is verified experimentally.

Keywords: dual sensing-actuator, electroactive polymers, hysteresis, position control

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Authors: W. M. Ng, O. B. Iskender, L. Simonini, J. M. Gonzalez

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A multitude of factors, including mechanical imperfections of the deployment system and separation instance of satellites from launchers, oftentimes results in highly uncontrolled initial tumbling motion immediately after deployment. In particular, small satellites which are characteristically launched as a piggyback to a large rocket, are generally allocated a large time window to complete detumbling within the early orbit phase. Because of the saturation risk of the actuators, current algorithms are conservative to avoid draining excessive power in the detumbling phase. This work aims to enable time-optimal switching of control modes during the early phase, reducing the time required to transit from launch to sun-pointing mode for power budget conscious satellites. This assumes the usage of B-dot controller for detumbling and PD controller for pointing. Nonlinear Euler's rotation equations are used to represent the attitude dynamics of satellites and Commercial-off-the-shelf (COTS) reaction wheels and magnetorquers are used to perform the manoeuver. Simulation results will be based on a spacecraft attitude simulator and the use case will be for multiple orbits of launch deployment general to Low Earth Orbit (LEO) satellites.

Keywords: attitude control, detumbling, small satellites, spacecraft autonomy, time optimal control

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Authors: Amina Babou

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Gender and language is a moot and miscellaneous arena in the sphere of socio-linguistics, which has been proliferated so widely and rapidly in recent years. The dawn of research on gender and foreign language education was against the feminist researchers who allowed space for the bustling concourse of voices and perspectives in the arena of gender and language differences, in the early to the mid-1970. The objective of this scrutiny is to explore to what extent teaching gender and language in the English as a Foreign Language (EFL) classroom plays a pivotal role in learning language information and skills. Moreover, the gist of this paper is to investigate how EFL students in Algeria conflate their gender identities with the linguistic practices and scholastic expertise. To grapple with the full range of issues about the EFL students’ awareness about the negotiation of meanings in the classroom, we opt for observing, interviewing, and questioning later to check using ‘how-do-you do’ procedure. The analysis of the EFL classroom discourse, from five Algerian universities, reveals that speaking strategies such as the manners students make an abrupt topic shifts, respond spontaneously to the teacher, ask more questions, interrupt others to seize control of conversations and monopolize the speaking floor through denying what others have said, do not sit very lightly on 80.4% of female students’ shoulders. The data indicate that female students display the assertive style as a strategy of learning to subvert the norms of femininity, especially in the speaking module.

Keywords: EFL students, gender identity, linguistic styles, foreign language

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Authors: Pieter De Vries, Renate Klaassen, Maria Ioannides

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This paper is about an explorative research into the use of emerging technologies for teaching and learning in higher engineering education. The assumption is that these technologies and applications, which are not yet widely adopted, will help to improve education and as such actively work on the ability to better deal with the mismatch of skills bothering our industries. Technologies such as 3D printing, the Internet of Things, Virtual Reality, and others, are in a dynamic state of development which makes it difficult to grasp the value for education. Also, the instruments in current educational research seem not appropriate to assess the value of such technologies. This explorative research aims to foster an approach to better deal with this new complexity. The need to find out is urgent, because these technologies will be dominantly present in the near future in all aspects of life, including education. The methodology used in this research comprised an inventory of emerging technologies and tools that potentially give way to innovation and are used or about to be used in technical universities. The inventory was based on both a literature review and a review of reports and web resources like blogs and others and included a series of interviews with stakeholders in engineering education and at representative industries. In addition, a number of small experiments were executed with the aim to analyze the requirements for the use of in this case Virtual Reality and the Internet of Things to better understanding the opportunities and limitations in the day-today learning environment. The major findings indicate that it is rather difficult to decide about the value of these technologies for education due to the dynamic state of change and therefor unpredictability and the lack of a coherent policy at the institutions. Most decisions are being made by teachers on an individual basis, who in their micro-environment are not equipped to select, test and ultimately decide about the use of these technologies. Most experiences are being made in the industry knowing that the skills to handle these technologies are in high demand. The industry though is worried about the inclination and the capability of education to help bridge the skills gap related to the emergence of new technologies. Due to the complexity, the diversity, the speed of development and the decay, education is challenged to develop an approach that can make these technologies work in an integrated fashion. For education to fully profit from the opportunities, these technologies offer it is eminent to develop a pro-active strategy and a sustainable approach to frame the emerging technologies development.

Keywords: emerging technologies, internet of things, pro-active strategy, virtual reality

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Authors: M. H. Korayem, Sh. Ameri, N. Yousefi Lademakhi

Abstract:

To ensure the stability of closed-loop nonlinear model predictive control (NMPC) within a finite horizon, there is a need for appropriate design terminal ingredients, which can be a time-consuming and challenging effort. Otherwise, in order to ensure the stability of the control system, it is necessary to consider an infinite predictive horizon. Increasing the prediction horizon increases computational demand and slows down the implementation of the method. In this study, a new technique has been proposed to ensure system stability without terminal ingredients. This technique has been employed in the design of the NMPC algorithm, leading to a reduction in the computational complexity of designing terminal ingredients and computational burden. The studied system is a wheeled mobile robot (WMR) subjected to non-holonomic constraints. Simulation has been investigated for two problems: trajectory tracking and adjustment mode.

Keywords: wheeled mobile robot, nonlinear model predictive control, stability, without terminal ingredients

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Authors: Jakub Adamec, Svatava Janouskova, Tomas Hak

Abstract:

The necessity of sustainable housing is explicitly embedded in ‘The 2030 agenda for sustainable development’, in particular, goal 11 ‘sustainable cities and communities’. Every UN member state is obligated to implement strategies from the agenda, including a strategy for sustainable housing into the practice in the local context. As shown in many countries, the lack of knowledge represses the adaptation process of sustainable strategies by governments. Hence, this study explores the concept of sustainable housing within the Czech Republic. The research elaborates on this term, and its current definition concerning ‘Geneva UN Charter on Sustainable Housing’. To this day, the charter represents the most comprehensive framework for a sustainable housing concept. Researchers conducted a comparative analysis of 38 international and 195 Czech national strategic documents. As a result, the charter‘s and strategic documents‘ goals were interconnected, identifying the most represented targets (e.g. improved environmental and energy performance of dwellings, resilient urban settlements which use renewable energy, and sustainable and integrated transport systems). The research revealed, even though the concept of sustainable housing is still dominated by environmental aspects, that social aspects significantly increased its importance. Additionally, this theoretical framework will serve as a foundation for the sustainable housing index development for the Czech Republic.

Keywords: comparative analysis, Czech national strategy, Geneva un charter, sustainable housing, urban theory

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Authors: Alexandre M. Brighenti

Abstract:

The experiment was carried out in Valença, Rio de Janeiro State, Brazil, to evaluate the selectivity and weed control of carotenoid biosynthesis inhibiting herbicides applied alone or in combination with atrazine in elephant grass crop. The treatments were as follows: mesotrione (0.072 and 0.144 kg ha^-1 + 0.5% v/v mineral oil - Assist®), tembotrione (0.075 and 0.100 kg ha^-1 + 0.5% v/v mineral oil - Aureo®), atrazine + mesotrione (1.25 + 0.072 kg ha^-1 + 0.5% v/v mineral oil - Assist®), atrazine + tembotrione (1.25 + 0.100 kg ha^-1 + 0.5% v/v mineral oil - Aureo®), atrazine + mesotrione (1.25 + 0.072 kg ha^-1), atrazine + tembotrione (1.25 + 0.100 kg ha^-1) and two controls (hoed and unhoed check). Two application rates of mesotrione with the addition of mineral oil or the tank mixture of atrazine plus mesotrione, with or without the addition of mineral oil, did not provide injuries capable to reduce elephant grass forage yield. Tembotrione was phytotoxic to elephant grass when applied with mineral oil. Atrazine and tembotrione in a tank-mix, with or without mineral oil, were also phytotoxic to elephant grass. All treatments provided satisfactory weed control.

Keywords: forage, Napier grass, pasture, Pennisetum purpureum, weeds

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Authors: A. Mansouri, F. Krim

Abstract:

This paper discusses the implementation and design of both linear PI and fuzzy controllers for DC-DC boost converters. Design of PI controllers is based on temporal response of closed-loop converters, while fuzzy controllers design is based on heuristic knowledge of boost converters. Linear controller implementation is quite straightforward relying on mathematical models, while fuzzy controller implementation employs one or more artificial intelligences techniques. Comparison between these boost controllers is made in design aspect. Experimental results show that the proposed fuzzy controller system is robust against input voltage and load resistance changing and in respect of start-up transient. Results indicate that fuzzy controller can achieve best control performance concerning faster transient response, steady-state response good stability and accuracy under different operating conditions. Fuzzy controller is more suitable to control boost converters.

Keywords: boost DC-DC converter, fuzzy, PI controllers, power electronics and control system

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Authors: Ishani Das, Avinash Padhi, Sitabja Mukherjee, Santosh Kar, Avinash Sonawane

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Activation of cell mediated and humoral immune responses to Mycobacterium tuberculosis (Mtb) are critical for protection. Herein, we show that mice immunized with Mtb lipid bound chitosan nanoparticles(NPs) induce secretion of prominent Th1 and Th2 cytokines in lymph node and spleen cells, and also induced significantly higher levels of IgG, IgG1, IgG2 and IgM in comparison to control mice measured by ELISA. Furthermore, significantly enhanced γδ-T cell activation was observed in lymph node cells isolated from mice immunized with Mtb lipid coated chitosan-NPs as compared to mice immunized with chitosan-NPs alone or Mtb lipid liposomes through flow cytometric analysis. Also, it was observed that in comparison to CD8+ cells, significantly higher CD4+ cells were present in both the lymph node and spleen cells isolated from mice immunized with Mtb lipid coated chitosan NP. In conclusion, this study represents a promising new strategy for efficient delivery of Mtb lipids using chitosan NPs to trigger enhanced cell mediated and antibody response against Mtb lipids.

Keywords: antibody response, chitosan nanoparticles, cytokines, mycobacterium tuberculosis lipids

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Authors: Manpreet Kaur, Amita Rani, Sanjay Kumar

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The Internet of Things (IoT), a cyber-physical paradigm, allows a large number of devices to connect and send the sensory data in the network simultaneously. This tremendous amount of data generated leads to very high network load consequently resulting in network congestion. It further amounts to frequent loss of useful information and depletion of significant amount of nodes’ energy. Therefore, there is a need to control congestion in IoT so as to prolong network lifetime and improve the quality of service (QoS). Hence, we propose a two-level clustering based routing algorithm considering congestion score and packet priority metrics that focus on minimizing the network congestion. In the proposed Priority based Congestion Control (PBCC) protocol the sensor nodes in IoT network form clusters that reduces the amount of traffic and the nodes are prioritized to emphasize important data. Simultaneously, a congestion score determines the occurrence of congestion at a particular node. The proposed protocol outperforms the existing Packet Discard Network Clustering (PDNC) protocol in terms of buffer size, packet transmission range, network region and number of nodes, under various simulation scenarios.

Keywords: internet of things, cyber-physical systems, congestion control, priority, transmission rate

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Authors: Jiunde Lee, Meng-Yu Wun

Abstract:

The present study attempted to explore how the range differences of ‘Geometric Field of Vision’ (GFOV) and differences in camera control in 3D simulation games, OMSI—The Bus Simulator of the 2013 PC version, affected players’ cognitive load, anxiety, and task performances. The study employed a between-subjects factorial experimental design. A total of 80 subjects completed experiment whose data were eligible for further analysis. The results of this study showed that in the difference of field of view, players had better task performances in a spacious view. Although cognitive resources consumed more of the players’ ‘mental demand,’ ‘physical demand’, and ‘temporal demand’, they had better performances in the experiment, and their anxiety was effectively reduced. On the other hand, in the narrow GFOV, players thought they spent more cognitive resources on ‘effort’ and ‘frustration degree,’ and had worse task performances, but it was not significant enough to reduce their anxiety. In terms of difference of camera control, players had worse performances since the fixed lens restricted their dexterous control. However, there was no significant difference in the players’ subjective cognitive resources or anxiety. The results further illustrated that task performances were affected by the interaction of GFOV and camera control.

Keywords: geometric field of view, camera lens, cognitive load, anxiety

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Authors: Pablo Raul Yanyachi, Alfredo Mamani Saico, Jorch Mendoza, Wang Xinsheng

Abstract:

The Attitude Determination and Control System (ADCS) plays a pivotal role in the operation of nanosatellites such as Cubesats, managing orientation and stability during space missions. Within the ADCS, Reaction Wheels (RW) are electromechanical devices responsible for adjusting and maintaining satellite orientation through the application of kinetic moments. This study focuses on the characterization and analysis of a specific Reaction Wheel integrated into an ADCS prototype developed at the National University of San Agust´ın, Arequipa (UNSA). To achieve this, a single-axis Test Bench was constructed, where the reaction wheel consists of a brushless motor and an inertia flywheel driven by an Electronic Speed Controller (ESC). The research encompasses RW characterization, energy consumption evaluation, dynamic modeling, and control. The results have allowed us to ensure the maneuverability of ADCS prototypes while maintaining energy consumption within acceptable limits. The characterization and linearity analysis provides valuable insights for sizing and optimizing future reaction wheel prototypes for nanosatellites. This contributes to the ongoing development of aerospace technology within the scientific community at UNSA.

Keywords: test bench, nanosatellite, control, reaction wheel

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