Search results for: soil erosion control
10520 Anticipating Asthma with Control Environmental Factors and Food
Authors: Destin Kurniawati
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Asthma is one of the deadly diseases in the world. According to the World Health Organization in 2012, 300 million people suffer from asthma of different races and classes. An estimated 250,000 people die because of asthma annually.As well as more than 57% of children and 51% of adults with asthma. There two risk factors for asthma. That risk factors are the host and environmental. One of the environmental factors that can bring asthma is allergens. When an allergen enters the body, the allergen binds to IgE and cause cell granulat- issued several mediators such as histamine, leukotrienes, bradykinin or something like that. This will cause localized edema effect on bronchial walls of small, thick mucous secretions in the bronchioles, and bronchial smooth muscle spasm. Then there will be inflammation of the airways. Methodology this research is by literature. Therefore, to anticipate and cope with asthma is to control environmental factors that serve to minimize allergens and controlling one's intake in the form of antioxidant-rich foods. Foods rich in antioxidants serve to improve lung function and decrease symptoms of the disease of the respiratory tract.Keywords: asthma, deadly disease, allergen, environmental and food control
Procedia PDF Downloads 26110519 The Effect of Fish and Krill Oil on Warfarin Control
Authors: Rebecca Pryce, Nijole Bernaitis, Andrew K. Davey, Shailendra Anoopkumar-Dukie
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Background: Warfarin is an oral anticoagulant widely used in the prevention of strokes in patients with atrial fibrillation (AF) and in the treatment and prevention of deep vein thrombosis (DVT). Regular monitoring of Internationalised Normalised Ratio (INR) is required to ensure therapeutic benefit with time in therapeutic range (TTR) used to measure warfarin control. A number of factors influence TTR including diet, concurrent illness, and drug interactions. Extensive literature exists regarding the effect of conventional medicines on warfarin control, but documented interactions relating to complementary medicines are limited. It has been postulated that fish oil and krill oil supplementation may affect warfarin due to their association with bleeding events. However, to date little is known as to whether fish and krill oil significantly alter the incidence of bleeding with warfarin or impact on warfarin control. Aim:To assess the influence of fish oil and krill oil supplementation on warfarin control in AF and DVT patients by determining the influence of these supplements on TTR and bleeding events. Methods:A retrospective cohort analysis was conducted utilising patient information from a large private pathology practice in Queensland. AF and DVT patients receiving warfarin management by the pathology practice were identified and their TTR calculated using the Rosendaal method. Concurrent medications were analysed and patients taking no other interacting medicines were identified and divided according to users of fish oil and krill oil supplements and those taking no supplements. Study variables included TTR and the incidence of bleeding with exclusion criteria being less than 30 days of treatment with warfarin. Subject characteristics were reported as the mean and standard deviation for continuous data and number and percentages for nominal or categorical data. Data was analysed using GraphPad InStat Version 3 with a p value of <0.05 considered to be statistically significant. Results:Of the 2081 patients assessed for inclusion into this study, a total of 573 warfarin users met the inclusion criteria. Of these, 416 (72.6%) patients were AF patients and 157 (27.4%) DVT patients and overall there were 316 (55.1%) male and 257 (44.9%) female patients. 145 patients were included in the fish oil/krill oil group (supplement) and 428 were included in the control group. The mean TTR of supplement users was 86.9% and for the control group 84.7% with no significant difference between these groups. Control patients experienced 1.6 times the number of minor bleeds per person compared to supplement patients and 1.2 times the number of major bleeds per person. However, this was not statistically significant nor was the comparison between thrombotic events. Conclusion: No significant difference was found between supplement and control patients in terms of mean TTR, the number of bleeds and thrombotic events. Fish oil and krill oil supplements when used concurrently with warfarin do not significantly affect warfarin control as measured by TTR and bleeding incidence.Keywords: atrial fibrillation, deep vein thormbosis, fish oil, krill oil, warfarin
Procedia PDF Downloads 30510518 Preservative Potentials of Piper Guineense on Roma Tomato (Solanum lycopersicum) Fruit
Authors: Grace O. Babarinde, Adegoke O.Gabriel, Rahman Akinoso, Adekanye Bosede R.
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Health risks associated with the use of synthetic chemicals to control post-harvest losses in fruit calls for use of natural biodegradable compounds. The potential of Piper guineense as postharvest preservative for Roma tomato (Solanum lycopersicum L.) was investigated. Freshly harvested red tomato (200 g) was dipped into five concentrations (1, 2, 3, 4 and 5% w/v) of P. guineense aqueous extract, while untreated fruits served as control. The samples were stored under refrigeration and analysed at 5-day interval for physico-chemical properties. P. guineense essential oil (EO) was characterised using GC-MS and its tomato preservative potential was evaluated. Percentage weight loss (PWL) in extract-treated tomato ranged from 0.0-0.68% compared to control (0.3-19.97%) during storage. Values obtained for firmness ranged from 8.23-16.88 N and 8.4 N in extract-treated and control. pH reduced from 5.4 to 4.5 and 3.7 in extract-treated and untreated samples, respectively. Highest value of Total Soluble Solid (1.8 °Brix) and maximum retention of Ascorbic acid (13.0 mg/100 g) were observed in 4% P. guineense-treated samples. Predominant P. guineense EO components were zingiberene (9.9%), linalool (10.7%), β-caryophyllene (12.6%), 1, 5-Heptadiene, 6-methyl-2-(4-methyl-3-cyclohexene-l-yl) (16.4%) and β-sesquiphellandrene (23.7%). Tomatoes treated with EO had lower PWL (5.2%) and higher firmness (14.2 N) than controls (15.3% and 11.9 N) respectively. The result indicates that P. guineense can be incorporated in to post harvest technology of Roma tomato fruit.Keywords: aqueous extract, essential oil, piper guineense, Roma tomato, storage condition
Procedia PDF Downloads 47610517 Studying the Structural Behaviour of RC Beams with Circular Openings of Different Sizes and Locations Using FE Method
Authors: Ali Shubbar, Hasanain Alwan, Ee Yu Phur, John McLoughlin, Ameer Al-khaykan
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This paper aims to investigate the structural behaviour of RC beams with circular openings of different sizes and locations modelled using ABAQUS FEM software. Seven RC beams with the dimensions of 1200 mm×150 mm×150 mm were tested under three-point loading. Group A consists of three RC beams incorporating circular openings with diameters of 40 mm, 55 mm and 65 mm in the shear zone. However, Group B consists of three RC beams incorporating circular openings with diameters of 40 mm, 55 mm and 65 mm in the flexural zone. The final RC beam did not have any openings, to provide a control beam for comparison. The results show that increasing the diameter of the openings increases the maximum deflection and the ultimate failure load decreases relative to the control beam. In the shear zone, the presence of the openings caused an increase in the maximum deflection ranging between 4% and 22% and a decrease in the ultimate failure load of between 26% and 36% compared to the control beam. However, the presence of the openings in the flexural zone caused an increase in the maximum deflection of between 1.5% and 19.7% and a decrease in the ultimate failure load of between 6% and 13% relative to the control beam. In this study, the optimum location for placing circular openings was found to be in the flexural zone of the beam with a diameter of less than 30% of the depth of the beam.Keywords: ultimate failure load, maximum deflection, shear zone and flexural zone
Procedia PDF Downloads 27510516 Intervention to Reduce Unhealthy Food and Increasing Food Safety Among Thai Children
Authors: Mayurachat Kanyamee, Srisuda Rassameepong, Narunest Chulakarn
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This experimental pretest-posttest control group design aimed to examine the effects of a family-based intervention on increasing fruit and vegetable intake and reduce fat and sugar intake and nutritional status among school-age children. Children were randomized to experimental 68 children and control 68 children. The experimental group received the intervention based on Social Cognitive Theory. The control group received the school’s usual educational program regarding healthy eating behavior. Data were collected via three questionnaires including: demographic characteristics; fruit and vegetable intake; and fat and sugar intake at baseline, sixteen weeks after baseline. Analysis of the data included the use of descriptive statistic and independent t-test. Results revealed the significant differences between the experimental and control group, regarding: fruit and vegetable intake, fat and sugar intake and nutritional status at sixteenth week after baseline. The findings suggest a family-based intervention, based on SCT, appears to be effective to improve eating behavior, and nutritional status of school -age children. So, the intervention can be applied to improve eating behavior among other groups of children.Keywords: family-based intervention, children, unhealthy food, food safety
Procedia PDF Downloads 27510515 Performance Evaluation of Wideband Code Division Multiplication Network
Authors: Osama Abdallah Mohammed Enan, Amin Babiker A/Nabi Mustafa
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The aim of this study is to evaluate and analyze different parameters of WCDMA (wideband code division multiplication). Moreover, this study also incorporates brief yet throughout analysis of WCDMA’s components as well as its internal architecture. This study also examines different power controls. These power controls may include open loop power control, closed or inner group loop power control and outer loop power control. Different handover techniques or methods of WCDMA are also illustrated in this study. These handovers may include hard handover, inter system handover and soft and softer handover. Different duplexing techniques are also described in the paper. This study has also presented an idea about different parameters of WCDMA that leads the system towards QoS issues. This may help the operator in designing and developing adequate network configuration. In addition to this, the study has also investigated various parameters including Bit Energy per Noise Spectral Density (Eb/No), Noise rise, and Bit Error Rate (BER). After simulating these parameters, using MATLAB environment, it was investigated that, for a given Eb/No value the system capacity increase by increasing the reuse factor. Besides that, it was also analyzed that, noise rise is decreasing for lower data rates and for lower interference levels. Finally, it was examined that, BER increase by using one type of modulation technique than using other type of modulation technique.Keywords: duplexing, handover, loop power control, WCDMA
Procedia PDF Downloads 21510514 Comparison of Fundamental Frequency Model and PWM Based Model for UPFC
Authors: S. A. Al-Qallaf, S. A. Al-Mawsawi, A. Haider
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Among all FACTS devices, the unified power flow controller (UPFC) is considered to be the most versatile device. This is due to its capability to control all the transmission system parameters (impedance, voltage magnitude, and phase angle). With the growing interest in UPFC, the attention to develop a mathematical model has increased. Several models were introduced for UPFC in literature for different type of studies in power systems. In this paper a novel comparison study between two dynamic models of UPFC with their proposed control strategies.Keywords: FACTS, UPFC, dynamic modeling, PWM, fundamental frequency
Procedia PDF Downloads 34610513 Computerized Adaptive Testing for Ipsative Tests with Multidimensional Pairwise-Comparison Items
Authors: Wen-Chung Wang, Xue-Lan Qiu
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Ipsative tests have been widely used in vocational and career counseling (e.g., the Jackson Vocational Interest Survey). Pairwise-comparison items are a typical item format of ipsative tests. When the two statements in a pairwise-comparison item measure two different constructs, the item is referred to as a multidimensional pairwise-comparison (MPC) item. A typical MPC item would be: Which activity do you prefer? (A) playing with young children, or (B) working with tools and machines. These two statements aim at the constructs of social interest and investigative interest, respectively. Recently, new item response theory (IRT) models for ipsative tests with MPC items have been developed. Among them, the Rasch ipsative model (RIM) deserves special attention because it has good measurement properties, in which the log-odds of preferring statement A to statement B are defined as a competition between two parts: the sum of a person’s latent trait to which statement A is measuring and statement A’s utility, and the sum of a person’s latent trait to which statement B is measuring and statement B’s utility. The RIM has been extended to polytomous responses, such as preferring statement A strongly, preferring statement A, preferring statement B, and preferring statement B strongly. To promote the new initiatives, in this study we developed computerized adaptive testing algorithms for MFC items and evaluated their performance using simulations and two real tests. Both the RIM and its polytomous extension are multidimensional, which calls for multidimensional computerized adaptive testing (MCAT). A particular issue in MCAT for MPC items is the within-person statement exposure (WPSE); that is, a respondent may keep seeing the same statement (e.g., my life is empty) for many times, which is certainly annoying. In this study, we implemented two methods to control the WPSE rate. In the first control method, items would be frozen when their statements had been administered more than a prespecified times. In the second control method, a random component was added to control the contribution of the information at different stages of MCAT. The second control method was found to outperform the first control method in our simulation studies. In addition, we investigated four item selection methods: (a) random selection (as a baseline), (b) maximum Fisher information method without WPSE control, (c) maximum Fisher information method with the first control method, and (d) maximum Fisher information method with the second control method. These four methods were applied to two real tests: one was a work survey with dichotomous MPC items and the other is a career interests survey with polytomous MPC items. There were three dependent variables: the bias and root mean square error across person measures, and measurement efficiency which was defined as the number of items needed to achieve the same degree of test reliability. Both applications indicated that the proposed MCAT algorithms were successful and there was no loss in measurement proficiency when the control methods were implemented, and among the four methods, the last method performed the best.Keywords: computerized adaptive testing, ipsative tests, item response theory, pairwise comparison
Procedia PDF Downloads 24610512 H∞robust Control Law for a Speed Dc Motor in Both Directions of Rotation
Authors: Ben Abdallah Aicha
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In this work we show a H∞ synthesis method which enables us to calculate a feedback controller according to considerations of stability robustness and disturbance rejection translated on to the open loop response. However, it may happen that we have an additional specification on the closed loop response relating to tracking of the reference trajectory. The H∞ synthesis has the advantage of offering increased specifications in robustness stability. Implemented for a DC motor, it offers invaluable performance in speed control in both directions of rotation.Keywords: H∞ synthesis, DC motor, robustness stability, performance conditions
Procedia PDF Downloads 8410511 Investigation of Natural Resource Sufficiency for Development of a Sustainable Agriculture Strategy Based on Permaculture in Malta
Authors: Byron Baron
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Typical of the Mediterranean region, the Maltese islands exhibit calcareous soils containing low organic carbon content and high salinity, in addition to being relatively shallow. This has lead to the common practice of applying copious amounts of artificial fertilisers as well as other chemical inputs, together with the use of ground water having high salinity. Such intensive agricultural activities, over a prolonged time period, on such land has lead further to the loss of any soil fertility, together with direct negative impacts on the quality of fresh water reserves and the local ecosystem. The aim of this study was to investigate whether the natural resources on the island would be sufficient to apply ecological intensification i.e. the use of natural processes to replace anthropological inputs without any significant loss in food production. This was implementing through a sustainable agricultural system based on permaculture practices. Ecological intensification following permaculture principles was implemented for two years in order to capture the seasonal changes in duplicate. The areas dedicated to wild plants were only trimmed back to avoid excessive seeding but never mowing. A number of local staple crops were grown throughout this period, also in duplicate. Concomitantly, a number of practices were implemented following permaculture principles such as reducing land tilling, applying only natural fertiliser, mulching, monitoring of soil parameters using sensors, no use of herbicides or pesticides, and precision irrigation linked to a desalination system. Numerous environmental parameters were measured at regular intervals so as to quantify any improvements in ecological conditions. Crop output was also measured as kilos of produce per area. The results clearly show that over the two year period, the variety of wild plant species increased, the number of visiting pollinators increased, there were no pest infestations (although an increase in the number of pests was observed), and a slight improvement in overall soil health was also observed. This was obviously limited by the short duration of the testing implementation. Dedicating slightly less than 15% of total land area to wild plants in the form of borders around plots of crops assisted pollination and provided a foraging area for gleaning bats (measured as an increased number of feeding buzzes) whilst not giving rise to any pest infestations and no apparent yield losses or ill effects to the crops. Observed increases in crop yields were not significant. The study concluded that with the right support for the initial establishment of a healthy ecosystem and controlled intervention, the available natural resources on the island can substantially improve the condition of the local agricultural land area, resulting is a more prolonged economical output with greater ecological sustainability. That being said, more comprehensive and long-term monitoring is required in order to fully validate these results and design a sustainable agriculture system that truly achieves the best outcome for the Maltese context.Keywords: ecological intensification, soil health, sustainable agriculture, permaculture
Procedia PDF Downloads 6510510 Novel Framework for MIMO-Enhanced Robust Selection of Critical Control Factors in Auto Plastic Injection Moulding Quality Optimization
Authors: Seyed Esmail Seyedi Bariran, Khairul Salleh Mohamed Sahari
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Apparent quality defects such as warpage, shrinkage, weld line, etc. are such an irresistible phenomenon in mass production of auto plastic appearance parts. These frequently occurred manufacturing defects should be satisfied concurrently so as to achieve a final product with acceptable quality standards. Determining the significant control factors that simultaneously affect multiple quality characteristics can significantly improve the optimization results by eliminating the deviating effect of the so-called ineffective outliers. Hence, a robust quantitative approach needs to be developed upon which major control factors and their level can be effectively determined to help improve the reliability of the optimal processing parameter design. Hence, the primary objective of current study was to develop a systematic methodology for selection of significant control factors (SCF) relevant to multiple quality optimization of auto plastic appearance part. Auto bumper was used as a specimen with the most identical quality and production characteristics to APAP group. A preliminary failure modes and effect analysis (FMEA) was conducted to nominate a database of pseudo significant significant control factors prior to the optimization phase. Later, CAE simulation Moldflow analysis was implemented to manipulate four rampant plastic injection quality defects concerned with APAP group including warpage deflection, volumetric shrinkage, sink mark and weld line. Furthermore, a step-backward elimination searching method (SESME) has been developed for systematic pre-optimization selection of SCF based on hierarchical orthogonal array design and priority-based one-way analysis of variance (ANOVA). The development of robust parameter design in the second phase was based on DOE module powered by Minitab v.16 statistical software. Based on the F-test (F 0.05, 2, 14) one-way ANOVA results, it was concluded that for warpage deflection, material mixture percentage was the most significant control factor yielding a 58.34% of contribution while for the other three quality defects, melt temperature was the most significant control factor with a 25.32%, 84.25%, and 34.57% contribution for sin mark, shrinkage and weld line strength control. Also, the results on the he least significant control factors meaningfully revealed injection fill time as the least significant factor for both warpage and sink mark with respective 1.69% and 6.12% contribution. On the other hand, for shrinkage and weld line defects, the least significant control factors were holding pressure and mold temperature with a 0.23% and 4.05% overall contribution accordingly.Keywords: plastic injection moulding, quality optimization, FMEA, ANOVA, SESME, APAP
Procedia PDF Downloads 34910509 Drivers of Land Degradation in Trays Ecosystem as Modulated under a Changing Climate: Case Study of Côte d'Ivoire
Authors: Kadio Valere R. Angaman, Birahim Bouna Niang
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Land degradation is a serious problem in developing countries, including Cote d’Ivoire, which has its economy focused on agriculture. It occurs in all kinds of ecosystems over the world. However, the drivers of land degradation vary from one region to another and from one ecosystem to another. Thus, identifying these drivers is an essential prerequisite to developing and implementing appropriate policies to reverse the trend of land degradation in the country, especially in the trays ecosystem. Using the binary logistic model with primary data obtained through 780 farmers surveyed, we analyze and identify the drivers of land degradation in the trays ecosystem. The descriptive statistics show that 52% of farmers interviewed have stated facing land degradation in their farmland. This high rate shows the extent of land degradation in this ecosystem. Also, the results obtained from the binary logit regression reveal that land degradation is significantly influenced by a set of variables such as sex, education, slope, erosion, pesticide, agricultural activity, deforestation, and temperature. The drivers identified are mostly local; as a result, the government must implement some policies and strategies that facilitate and incentive the adoption of sustainable land management practices by farmers to reverse the negative trend of land degradation.Keywords: drivers, land degradation, trays ecosystem, sustainable land management
Procedia PDF Downloads 14510508 Phenotypic and Symbiotic Characterization of Rhizobia Isolated from Faba Bean (Vicia faba L.) in Moroccan Soils
Authors: Y. Hajjam, I. T. Alami, S. M. Udupa, S. Cherkaoui
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Faba bean (Vicia faba L.) is an important food legume crop in Morocco. It is mainly used as human food and feed for animals. Faba bean also plays an important role in cereal-based cropping systems, when rotated with cereals it improves soil fertility by fixing N2 in root nodules mediated by Rhizobium. Both faba bean and its biological nitrogen fixation symbiotic bacterium Rhizobium are affected by different stresses such as: salinity, drought, pH, heavy metal, and the uptake of inorganic phosphate compounds. Therefore, the aim of the present study was to evaluate the phenotypic diversity among the faba bean rhizobial isolates and to select the tolerant strains that can fix N2 under environmental constraints for inoculation particularly for affected soils, in order to enhance the productivity of faba bean and to improve soil fertility. Result have shown that 62% of isolates were fast growing with the ability of producing acids compounds , while 38% of isolates are slow growing with production of alkalins. Moreover, 42.5% of these isolates were able to solubilize inorganic phosphate Ca3(PO4)2 and the index of solubilization was ranged from 2.1 to 3.0. The resistance to extreme pH, temperature, water stress heavy metals and antibiotics lead us to classify rhizobial isolates into different clusters. Finally, the authentication test under greenhouse conditions showed that 55% of the rhizobial isolates could induce nodule formation on faba bean (Vicia faba L.) under greenhouse experiment. This phenotypic characterization may contribute to improve legumes and non legumes crops especially in affected soils and also to increase agronomic yield in the dry areas.Keywords: rhizobia, vicia faba, phenotypic characterization, nodule formation, environmental constraints
Procedia PDF Downloads 25210507 Broad Survey of Fine Root Traits to Investigate the Root Economic Spectrum Hypothesis and Plant-Fire Dynamics Worldwide
Authors: Jacob Lewis Watts, Adam F. A. Pellegrini
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Prairies, grasslands, and forests cover an expansive portion of the world’s surface and contribute significantly to Earth’s carbon cycle. The largest driver of carbon dynamics in some of these ecosystems is fire. As the global climate changes, most fire-dominated ecosystems will experience increased fire frequency and intensity, leading to increased carbon flux into the atmosphere and soil nutrient depletion. The plant communities associated with different fire regimes are important for reassimilation of carbon lost during fire and soil recovery. More frequent fires promote conservative plant functional traits aboveground; however, belowground fine root traits are poorly explored and arguably more important drivers of ecosystem function as the primary interface between the soil and plant. The root economic spectrum (RES) hypothesis describes single-dimensional covariation between important fine-root traits along a range of plant strategies from acquisitive to conservative – parallel to the well-established leaf economic spectrum (LES). However, because of the paucity of root trait data, the complex nature of the rhizosphere, and the phylogenetic conservatism of root traits, it is unknown whether the RES hypothesis accurately describes plant nutrient and water acquisition strategies. This project utilizesplants grown in common garden conditions in the Cambridge University Botanic Garden and a meta-analysis of long-term fire manipulation experiments to examine the belowground physiological traits of fire-adapted and non-fire-adapted herbaceous species to 1) test the RES hypothesis and 2) describe the effect of fire regimes on fine root functional traits – which in turn affect carbon and nutrient cycling. A suite of morphological, chemical, and biological root traits (e.g. root diameter, specific root length, percent N, percent mycorrhizal colonization, etc.) of 50 herbaceous species were measuredand tested for phylogenetic conservatism and RES dimensionality. Fire-adapted and non-fire-adapted plants traits were compared using phylogenetic PCA techniques. Preliminary evidence suggests that phylogenetic conservatism may weaken the single-dimensionality of the RES, suggesting that there may not be a single way that plants optimize nutrient and water acquisition and storage in the complex rhizosphere; additionally, fire-adapted species are expected to be more conservative than non-fire-adapted species, which may be indicative of slower carbon cycling with increasing fire frequency and intensity.Keywords: climate change, fire regimes, root economic spectrum, fine roots
Procedia PDF Downloads 12310506 Model Reference Adaptive Approach for Power System Stabilizer for Damping of Power Oscillations
Authors: Jožef Ritonja, Bojan Grčar, Boštjan Polajžer
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In recent years, electricity trade between neighboring countries has become increasingly intense. Increasing power transmission over long distances has resulted in an increase in the oscillations of the transmitted power. The damping of the oscillations can be carried out with the reconfiguration of the network or the replacement of generators, but such solution is not economically reasonable. The only cost-effective solution to improve the damping of power oscillations is to use power system stabilizers. Power system stabilizer represents a part of synchronous generator control system. It utilizes semiconductor’s excitation system connected to the rotor field excitation winding to increase the damping of the power system. The majority of the synchronous generators are equipped with the conventional power system stabilizers with fixed parameters. The control structure of the conventional power system stabilizers and the tuning procedure are based on the linear control theory. Conventional power system stabilizers are simple to realize, but they show non-sufficient damping improvement in the entire operating conditions. This is the reason that advanced control theories are used for development of better power system stabilizers. In this paper, the adaptive control theory for power system stabilizers design and synthesis is studied. The presented work is focused on the use of model reference adaptive control approach. Control signal, which assures that the controlled plant output will follow the reference model output, is generated by the adaptive algorithm. Adaptive gains are obtained as a combination of the "proportional" term and with the σ-term extended "integral" term. The σ-term is introduced to avoid divergence of the integral gains. The necessary condition for asymptotic tracking is derived by means of hyperstability theory. The benefits of the proposed model reference adaptive power system stabilizer were evaluated as objectively as possible by means of a theoretical analysis, numerical simulations and laboratory realizations. Damping of the synchronous generator oscillations in the entire operating range was investigated. Obtained results show the improved damping in the entire operating area and the increase of the power system stability. The results of the presented work will help by the development of the model reference power system stabilizer which should be able to replace the conventional stabilizers in power systems.Keywords: power system, stability, oscillations, power system stabilizer, model reference adaptive control
Procedia PDF Downloads 13810505 Efficacy of Sea Water with Reduced Rate Herbicide to Control Weeds in Tropical Turf
Authors: Md. Kamal Uddin, Abdul Shukor Juraimi, Md. Parvez Anwar
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Seawater with reduced herbicide could be considered as a low cost environment friendly alternative method for weed control in turfgrass. Different concentration of sea water in combination with trifloxysulfuron-sodium and quinclorac were used to determine weed control level in turfgrass field. The weed species S. diander, C. aromaticus, and C. rotundus except E. atrovirens were fully controlled when treated with ¾ recommended trifloxysulfuron–sodium with sea water, ¾ recommended trifloxysulfuron–sodium with ¾ sea water, ½ recommended trifloxysulfuron–sodium with sea water, ¾ recommended quinclorac with sea water and ¾ recommended quinclorac with ¾ sea water. Eragrostis atrovirens showed maximum 48% injury when treated with ¾ recommended trifloxysulfuron–sodium and sea water. Among the tested turf grasses, P. vaginatum showed only 8% injury to sea water in combination with ¾ recommended quinclorac, indicating greater salt tolerance. Zoysia japonica also showed no more than 14% injury when treated with sea water in combination with ¾ recommended trifloxysulfuron–sodium or quinclorac.Keywords: sea water, trifloxysulfuron–sodium, quinclorac, turf
Procedia PDF Downloads 38110504 Dynamic Analysis of Mono-Pile: Spectral Element Method
Authors: Rishab Das, Arnab Banerjee, Bappaditya Manna
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Mono-pile foundations are often used in soft soils in order to support heavy mega-structures, whereby often these deep footings may undergo dynamic excitation due to many causes like earthquake, wind or wave loads acting on the superstructure, blasting, and unbalanced machines, etc. A comprehensive analytical study is performed to study the dynamics of the mono-pile system embedded in cohesion-less soil. The soil is considered homogeneous and visco-elastic in nature and is analytically modeled using complex springs. Considering the N number of the elements of the pile, the final global stiffness matrix is obtained by using the theories of the spectral element matrix method. Further, statically condensing the intermediate internal nodes of the global stiffness matrix results to a smaller sub matrix containing the nodes experiencing the external translation and rotation, and the stiffness and damping functions (impedance functions) of the embedded piles are determined. Proper plots showing the variation of the real and imaginary parts of these impedance functions with the dimensionless frequency parameter are obtained. The plots obtained from this study are validated by that provided by Novak,1974. Further, the dynamic analysis of the resonator impregnated pile is proposed within this study. Moreover, with the aid of Wood's 1g laboratory scaling law, a proper scaled-down resonator-pile model is 3D printed using PLA material. Dynamic analysis of the scaled model is carried out in the time domain, whereby the lateral loads are imposed on the pile head. The response obtained from the sensors through the LabView software is compared with the proposed theoretical data.Keywords: mono-pile, visco-elastic, impedance, LabView
Procedia PDF Downloads 11810503 Effects of Self-Management Programs on Blood Pressure Control, Self-Efficacy, Medication Adherence, and Body Mass Index among Older Adult Patients with Hypertension: Meta-Analysis of Randomized Controlled Trials
Authors: Van Truong Pham
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Background: Self-management was described as a potential strategy for blood pressure control in patients with hypertension. However, the effects of self-management interventions on blood pressure, self-efficacy, medication adherence, and body mass index (BMI) in older adults with hypertension have not been systematically evaluated. We evaluated the effects of self-management interventions on systolic blood pressure (SBP) and diastolic blood pressure (DBP), self-efficacy, medication adherence, and BMI in hypertensive older adults. Methods: We followed the recommended guidelines of preferred reporting items for systematic reviews and meta-analyses. Searches in electronic databases including CINAHL, Cochrane Library, Embase, Ovid-Medline, PubMed, Scopus, Web of Science, and other sources were performed to include all relevant studies up to April 2019. Studies selection, data extraction, and quality assessment were performed by two reviewers independently. We summarized intervention effects as Hedges' g values and 95% confidence intervals (CI) using a random-effects model. Data were analyzed using Comprehensive Meta-Analysis software 2.0. Results: Twelve randomized controlled trials met our inclusion criteria. The results revealed that self-management interventions significantly improved blood pressure control, self-efficacy, medication adherence, whereas the effect of self-management on BMI was not significant in older adult patients with hypertension. The following Hedges' g (effect size) values were obtained: SBP, -0.34 (95% CI, -0.51 to -0.17, p < 0.001); DBP, -0.18 (95% CI, -0.30 to -0.05, p < 0.001); self-efficacy, 0.93 (95%CI, 0.50 to 1.36, p < 0.001); medication adherence, 1.72 (95%CI, 0.44 to 3.00, p=0.008); and BMI, -0.57 (95%CI, -1.62 to 0.48, p = 0.286). Conclusions: Self-management interventions significantly improved blood pressure control, self-efficacy, and medication adherence. However, the effects of self-management on obesity control were not supported by the evidence. Healthcare providers should implement self-management interventions to strengthen patients' role in managing their health care.Keywords: self-management, meta-analysis, blood pressure control, self-efficacy, medication adherence, body mass index
Procedia PDF Downloads 12810502 An Algorithm Based on Control Indexes to Increase the Quality of Service on Cellular Networks
Authors: Rahman Mofidi, Sina Rahimi, Farnoosh Darban
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Communication plays a key role in today’s world, and to support it, the quality of service has the highest priority. It is very important to differentiate between traffic based on priority level. Some traffic classes should be a higher priority than other classes. It is also necessary to give high priority to customers who have more payment for better service, however, without influence on other customers. So to realize that, we will require effective quality of service methods. To ensure the optimal performance of the network in accordance with the quality of service is an important goal for all operators in the mobile network. In this work, we propose an algorithm based on control parameters which it’s based on user feedback that aims at minimizing the access to system transmit power and thus improving the network key performance indicators and increasing the quality of service. This feedback that is known as channel quality indicator (CQI) indicates the received signal level of the user. We aim at proposing an algorithm in control parameter criterion to study improving the quality of service and throughput in a cellular network at the simulated environment. In this work we tried to parameter values have close to their actual level. Simulation results show that the proposed algorithm improves the system throughput and thus satisfies users' throughput and improves service to set up a successful call.Keywords: quality of service, key performance indicators, control parameter, channel quality indicator
Procedia PDF Downloads 20310501 Design of Real Time Early Response Systems for Natural Disaster Management Based on Automation and Control Technologies
Authors: C. Pacheco, A. Cipriano
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A new concept of response system is proposed for filling the gap that exists in reducing vulnerability during immediate response to natural disasters. Real Time Early Response Systems (RTERSs) incorporate real time information as feedback data for closing control loop and for generating real time situation assessment. A review of the state of the art works that fit the concept of RTERS is presented, and it is found that they are mainly focused on manmade disasters. At the same time, in response phase of natural disaster management many works are involved in creating early warning systems, but just few efforts have been put on deciding what to do once an alarm is activated. In this context a RTERS arises as a useful tool for supporting people in their decision making process during natural disasters after an event is detected, and also as an innovative context for applying well-known automation technologies and automatic control concepts and tools.Keywords: disaster management, emergency response system, natural disasters, real time
Procedia PDF Downloads 44510500 Victimization in Schizophrenia: A Cross-Sectional Prospective Study
Authors: Mehmet Budak, Mehmet Fatih Ustundag
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Objectives: In this research, we studied the extent of exposure to physical violence and committing violence in patients diagnosed with schizophrenia in comparison to a control group consisting of patients with psychiatric diseases other than psychotic and mood disorders. Method: Between August 2019 and October 2019, a total of 100 hospitalized patients diagnosed with schizophrenia (clinically in remission, Brief Psychiatric Rate Scale < 30) were sequentially studied while undergoing inpatient treatment at Erenkoy Mental Health Training and Research Hospital. From the outpatient clinic, 50 patients with psychiatric disorders other than psychotic disorders or mood disorders were consecutively included as a control group. All participants were evaluated by the sociodemographic data that also questions the history of violence, physical examination, bilateral comparative hand, and forearm anterior-posterior and lateral radiography. Results: While 59% of patients with schizophrenia and 28% of the control group stated that they were exposed to physical violence at least once in a lifetime (p < 0,001); a defensive wound or fracture was detected in 29% of patients with schizophrenia and 2% of the control group (p < 0.001). On the other hand, 61% of patients diagnosed with schizophrenia, and 32% of the control group expressed that they committed physical violence at least once in a lifetime (p: 0.001). A self-destructive wound or fracture was detected in 53% of the patients with schizophrenia and 24% of the control group (p: 0,001). In the schizophrenia group, the rate of committing physical violence is higher in those with substance use compared to those without substance use (p:0.049). Also, wounds and bone fractures (boxer’s fracture) resulting from self-injury are more common in schizophrenia patients with substance use (p:0,002). In the schizophrenia group, defensive wounds and parry fractures (which are located in the hand, forearm, and arm usually occur as a result of a trial to shield the face against an aggressive attack and are known to be the indicators of interpersonal violence) are higher in those with substance use compared to those who do not (p:0,007). Conclusion: This study shows that exposure to physical violence and the rate of violence is higher in patients with schizophrenia compared to the control group. It is observed that schizophrenia patients who are stigmatized as being aggressive are more exposed to violence. Substance use in schizophrenia patients increases both exposure to physical violence and the use of physical violence. Physical examination and anamnesis that question violence are important tools to reveal the exposure to violence in patients. Furthermore, some specific bone fractures and wounds could be used to detect victimization even after plenty of time passes.Keywords: fracture, physical violence, schizophrenia, substance use
Procedia PDF Downloads 16910499 Evaluation of Commercial Herbicides for Weed Control and Yield under Direct Dry Seeded Rice Cultivation System in Pakistan
Authors: Sanaullah Jalil, Abid Majeed, Syed Haider Abbas
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Direct dry seeded rice cultivation system is an emerging production technology in Pakistan. Weeds are a major constraint to the success of direct dry seeded rice (DDSR). Studies were carried out for two years during 2015 and 2016 to evaluate the performance of applications of pre-emergence herbicides (Top Max @ 2.25 lit/ha, Click @1.5 lit/ha and Pendimethaline @ 1.25 lit/ha) and post-emergence herbicides (Clover @ 200 g/ha, Pyranex Gold @ 250 g/ha, Basagran @ 2.50 lit/ha, Sunstar Gold @ 50 g/ha and Wardan @ 1.25 lit/ha) at rice research field area of National Agriculture Research Center (NARC), Islamabad. The experiments were laid out in Randomized Complete Block Design (RCBD) with three replications. All evaluated herbicides reduced weed density and biomass by a significant amount. The net plot size was 2.5 x 5 m with 10 rows. Basmati-385 was used as test variety of rice. Data indicated that Top Max and Click provided best weed control efficiency but suppressed the germination of rice seed which causes the lowest grain yield production (680.6 kg/ha and 314.5 kg/ha respectively). A weedy check plot contributed 524.7 kg/ha paddy yield with highest weed density. Pyranex Gold provided better weed control efficiency and contributed to significantly higher paddy yield 5116.6 kg/ha than that of all other herbicide applications followed by the Clover which give paddy yield 4241.7 kg/ha. The results of our study suggest that pre-emergence herbicides provided best weed control but not fit for direct dry seeded rice (DDSR) cultivation system, and therefore post-emergence herbicides (Pyranex Gold and Clover) can be suggested for weed control and higher yield.Keywords: pyranex gold, clover, direct dry seeded rice (DDSR), yield
Procedia PDF Downloads 26110498 An Elasto-Viscoplastic Constitutive Model for Unsaturated Soils: Numerical Implementation and Validation
Authors: Maria Lazari, Lorenzo Sanavia
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Mechanics of unsaturated soils has been an active field of research in the last decades. Efficient constitutive models that take into account the partial saturation of soil are necessary to solve a number of engineering problems e.g. instability of slopes and cuts due to heavy rainfalls. A large number of constitutive models can now be found in the literature that considers fundamental issues associated with the unsaturated soil behaviour, like the volume change and shear strength behaviour with suction or saturation changes. Partially saturated soils may either expand or collapse upon wetting depending on the stress level, and it is also possible that a soil might experience a reversal in the volumetric behaviour during wetting. Shear strength of soils also changes dramatically with changes in the degree of saturation, and a related engineering problem is slope failures caused by rainfall. There are several states of the art reviews over the last years for studying the topic, usually providing a thorough discussion of the stress state, the advantages, and disadvantages of specific constitutive models as well as the latest developments in the area of unsaturated soil modelling. However, only a few studies focused on the coupling between partial saturation states and time effects on the behaviour of geomaterials. Rate dependency is experimentally observed in the mechanical response of granular materials, and a viscoplastic constitutive model is capable of reproducing creep and relaxation processes. Therefore, in this work an elasto-viscoplastic constitutive model for unsaturated soils is proposed and validated on the basis of experimental data. The model constitutes an extension of an existing elastoplastic strain-hardening constitutive model capable of capturing the behaviour of variably saturated soils, based on energy conjugated stress variables in the framework of superposed continua. The purpose was to develop a model able to deal with possible mechanical instabilities within a consistent energy framework. The model shares the same conceptual structure of the elastoplastic laws proposed to deal with bonded geomaterials subject to weathering or diagenesis and is capable of modelling several kinds of instabilities induced by the loss of hydraulic bonding contributions. The novelty of the proposed formulation is enhanced with the incorporation of density dependent stiffness and hardening coefficients in order to allow the modeling of the pycnotropy behaviour of granular materials with a single set of material constants. The model has been implemented in the commercial FE platform PLAXIS, widely used in Europe for advanced geotechnical design. The algorithmic strategies adopted for the stress-point algorithm had to be revised to take into account the different approach adopted by PLAXIS developers in the solution of the discrete non-linear equilibrium equations. An extensive comparison between models with a series of experimental data reported by different authors is presented to validate the model and illustrate the capability of the newly developed model. After the validation, the effectiveness of the viscoplastic model is displayed by numerical simulations of a partially saturated slope failure of the laboratory scale and the effect of viscosity and degree of saturation on slope’s stability is discussed.Keywords: PLAXIS software, slope, unsaturated soils, Viscoplasticity
Procedia PDF Downloads 22510497 Boiling Effect of Momordica charantia with Salt to the Antihiperglicemia Effectiveness of Diabetes Mellitus Rats
Authors: Zulfa D. Putri, Jumayanti Jumayanti, Hatiefah T. I. Melati, Kiki Indriati, Farah U. Mauhibah
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Momordica charantia is a food that is often used for nutrition therapy for patients with Diabetes Mellitus (DM) because of its effect as antihiperglicemia. However, the bitter taste of Momordica charantia may be an obstacle to consume. Some people remove the bitter taste of this by boiling it with salt water. The purpose of this study was to determine the effect of Momordica charantia boiling with salt water in lowering blood glucose levels. This study is a quasi-experimental study with pre-post test with control group design. The research sample consisted of 25 rats Sprague-Dawley were divided into 5 groups: Control group of healthy, control group of DM, control group of DM with the addition of Momordica charantia are boiled by salt for 3 minutes, 6 minutes, and 9 minutes. Blood glucose levels were measured after 4 weeks using a spectrophotometer. These results indicate that there is the effect of bitter taste from Momordica charantia in lowering blood glucose levels in rats significantly. The conclusion of this study is giving a Momordica charantia juice in Sprague-Dawley rats that induced by alloxan has meaningful statistically proven by One Way ANOVA test (p = 0.00) in lowering blood glucose levels of rats.Keywords: antihiperglicemia, diabetes mellitus, momordica charantia, salt
Procedia PDF Downloads 23110496 Assessment of Sediment Control Characteristics of Notches in Different Sediment Transport Regimes
Authors: Chih Ming Tseng
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Landslides during typhoons that generate substantial amounts of sediment and subsequent rainfall can trigger various types of sediment transport regimes, such as debris flows, high-concentration sediment-laden flows, and typical river sediment transport. This study aims to investigate the sediment control characteristics of natural notches within different sediment transport regimes. High-resolution digital terrain models were used to establish the relationship between slope gradients and catchment areas, which were then used to delineate distinct sediment transport regimes and analyze the sediment control characteristics of notches within these regimes. The research results indicate that the catchment areas of Aiyuzi Creek, Hossa Creek, and Chushui Creek in the study region can be clearly categorized into three sediment transport regimes based on the slope-area relationship curves: frequent collapse headwater areas, debris flow zones, and high-concentration sediment-laden flow zones. The threshold for transitioning from the collapse zone to the debris flow zone in the Aiyuzi Creek catchment is lower compared to Hossa Creek and Chushui Creek, suggesting that the active collapse processes in the upper reaches of Aiyuzi Creek continuously supply a significant sediment source, making it more susceptible to subsequent debris flow events. Moreover, the analysis of sediment trapping efficiency at notches within different sediment transport regimes reveals that as the notch constriction ratio increases, the sediment accumulation per unit area also increases. The accumulation thickness per unit area in high-concentration sediment-laden flow zones is greater than in debris flow zones, indicating differences in sediment deposition characteristics among various sediment transport regimes. Regarding sediment control rates at notches, there is a generally positive correlation with the notch constriction ratio. During the 2009 Morakot Typhoon, the substantial sediment supply from slope failures in the upstream catchment led to an oversupplied sediment transport condition in the river channel. Consequently, sediment control rates were more pronounced during medium and small sediment transport events between 2010 and 2015. However, there were no significant differences in sediment control rates among the different sediment transport regimes at notches. Overall, this research provides valuable insights into the sediment control characteristics of notches under various sediment transport conditions, which can aid in the development of improved sediment management strategies in watersheds.Keywords: landslide, debris flow, notch, sediment control, DTM, slope–area relation
Procedia PDF Downloads 2810495 Effect of Multi-Enzyme Supplementation on Growth Performance of Broiler
Authors: Abdur Rahman, Saima, T. N. Pasha, Muhammad Younus, Yassar Abbas, Shahid Jaleel
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Non-starch polysaccharides (NSPs) are not completely digested by broiler endogenous enzymes and consequently the soluble NSPs in feed results in high digesta viscosity and poor retention of nutrients. Supplementation of NSPs digesting enzymes may release the nutrients from feed and reduce the anti-nutritional effects of NSP’s. The present study was conducted to determine the effects of NSPs digesting enzymes (Zympex) in broiler chicks. A total of 120 day old broiler chicks (Hubbard) were categorized into 3 treatments and each treatment was having four replicates with 10 birds in each. Dietary treatments comprised of Basal diet (2740 KCal/Kg) as control-1 (T1), low energy diet (2630 KCal/kg) control-2 (T2) and low energy diet with 0.5 gm/Kg enzyme as T3. Multi-enzymes supplementation showed significant (P < 0.05) positive effect on weight gain (last three weeks), feed intake (last two weeks), FCR (1st, 2nd, 4th and 5th) and nutrient retention in T3 when compared with control-2. Weight gain was lower (P < 0.05) in low caloric feed group C when compared with control-1 in all weeks except last week (P > 0.05), feed consumption was significantly lower (P < 0.05) in 5th week and results showed significantly poor FCR (P < 0.05) in 2nd, 3rd and 4th week but non-significant effect in 1st and 5th week when compared with control-1 group, which revealed the positive effect of enzyme supplementation in low energy diet. These results revealed that enzyme supplementation releases more energy from low energy diets and results in equal performance to normal diet.Keywords: body weight, FCR, feed intake, enzyme, non-starch polysaccharides
Procedia PDF Downloads 34910494 VTOL-Fw Mode-Transitioning UAV Design and Analysis
Authors: Feri̇t Çakici, M. Kemal Leblebi̇ci̇oğlu
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In this study, an unmanned aerial vehicle (UAV) with level flight, vertical take-off and landing (VTOL) and mode-transitioning capability is designed and analyzed. The platform design combines both multirotor and fixed-wing (FW) conventional airplane structures and control surfaces; therefore named as VTOL-FW. The aircraft is modeled using aerodynamical principles and linear models are constructed utilizing small perturbation theory for trim conditions. The proposed method of control includes implementation of multirotor and airplane mode controllers and design of an algorithm to transition between modes in achieving smooth switching maneuvers between VTOL and FW flight. Thus, VTOL-FW UAV’s flight characteristics are expected to be improved by enlarging operational flight envelope through enabling mode-transitioning, agile maneuvers and increasing survivability. Experiments conducted in simulation and real world environments shows that VTOL-FW UAV has both multirotor and airplane characteristics with extra benefits in an enlarged flight envelope.Keywords: aircraft design, linear analysis, mode transitioning control, UAV
Procedia PDF Downloads 39510493 Silicon-To-Silicon Anodic Bonding via Intermediate Borosilicate Layer for Passive Flow Control Valves
Authors: Luc Conti, Dimitry Dumont-Fillon, Harald van Lintel, Eric Chappel
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Flow control valves comprise a silicon flexible membrane that deflects against a substrate, usually made of glass, containing pillars, an outlet hole, and anti-stiction features. However, there is a strong interest in using silicon instead of glass as substrate material, as it would simplify the process flow by allowing the use of well controlled anisotropic etching. Moreover, specific devices demanding a bending of the substrate would also benefit from the inherent outstanding mechanical strength of monocrystalline silicon. Unfortunately, direct Si-Si bonding is not easily achieved with highly structured wafers since residual stress may prevent the good adhesion between wafers. Using a thermoplastic polymer, such as parylene, as intermediate layer is not well adapted to this design as the wafer-to-wafer alignment is critical. An alternative anodic bonding method using an intermediate borosilicate layer has been successfully tested. This layer has been deposited onto the silicon substrate. The bonding recipe has been adapted to account for the presence of the SOI buried oxide and intermediate glass layer in order not to exceed the breakdown voltage. Flow control valves dedicated to infusion of viscous fluids at very high pressure have been made and characterized. The results are compared to previous data obtained using the standard anodic bonding method.Keywords: anodic bonding, evaporated glass, flow control valve, drug delivery
Procedia PDF Downloads 20010492 Intelligent Control of Agricultural Farms, Gardens, Greenhouses, Livestock
Authors: Vahid Bairami Rad
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The intelligentization of agricultural fields can control the temperature, humidity, and variables affecting the growth of agricultural products online and on a mobile phone or computer. Smarting agricultural fields and gardens is one of the best and best ways to optimize agricultural equipment and has a 100 percent direct effect on the growth of plants and agricultural products and farms. Smart farms are the topic that we are going to discuss today, the Internet of Things and artificial intelligence. Agriculture is becoming smarter every day. From large industrial operations to individuals growing organic produce locally, technology is at the forefront of reducing costs, improving results and ensuring optimal delivery to market. A key element to having a smart agriculture is the use of useful data. Modern farmers have more tools to collect intelligent data than in previous years. Data related to soil chemistry also allows people to make informed decisions about fertilizing farmland. Moisture meter sensors and accurate irrigation controllers have made the irrigation processes to be optimized and at the same time reduce the cost of water consumption. Drones can apply pesticides precisely on the desired point. Automated harvesting machines navigate crop fields based on position and capacity sensors. The list goes on. Almost any process related to agriculture can use sensors that collect data to optimize existing processes and make informed decisions. The Internet of Things (IoT) is at the center of this great transformation. Internet of Things hardware has grown and developed rapidly to provide low-cost sensors for people's needs. These sensors are embedded in IoT devices with a battery and can be evaluated over the years and have access to a low-power and cost-effective mobile network. IoT device management platforms have also evolved rapidly and can now be used securely and manage existing devices at scale. IoT cloud services also provide a set of application enablement services that can be easily used by developers and allow them to build application business logic. Focus on yourself. These development processes have created powerful and new applications in the field of Internet of Things, and these programs can be used in various industries such as agriculture and building smart farms. But the question is, what makes today's farms truly smart farms? Let us put this question in another way. When will the technologies associated with smart farms reach the point where the range of intelligence they provide can exceed the intelligence of experienced and professional farmers?Keywords: food security, IoT automation, wireless communication, hybrid lifestyle, arduino Uno
Procedia PDF Downloads 5610491 Quantitative Changes in Biofilms of a Seawater Tubular Heat Exchanger Subjected to Electromagnetic Fields Treatment
Authors: Sergio Garcia, Alfredo Trueba, Luis M. Vega, Ernesto Madariaga
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Biofilms adhesion is one of the more important cost of industries plants on wide world, which use to water for cooling heat exchangers or are in contact with water. This study evaluated the effect of Electromagnetic Fields on biofilms in tubular heat exchangers using seawater cooling. The results showed an up to 40% reduction of the biofilm thickness compared to the untreated control tubes. The presence of organic matter was reduced by 75%, the inorganic mater was reduced by 87%, and 53% of the dissolved solids were eliminated. The biofilm thermal conductivity in the treated tube was reduced by 53% as compared to the control tube. The hardness in the effluent during the experimental period was decreased by 18% in the treated tubes compared with control tubes. Our results show that the electromagnetic fields treatment has a great potential in the process of removing biofilms in heat exchanger.Keywords: biofilm, heat exchanger, electromagnetic fields, seawater
Procedia PDF Downloads 191