Search results for: controllable and uncontrollable domestic loads
2130 Optimal Scheduling of Load and Operational Strategy of a Load Aggregator to Maximize Profit with PEVs
Authors: Md. Shafiullah, Ali T. Al-Awami
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This project proposes optimal scheduling of imported power of a load aggregator with the utilization of EVs to maximize its profit. As with the increase of renewable energy resources, electricity price in competitive market becomes more uncertain and, on the other hand, with the penetration of renewable distributed generators in the distribution network the predicted load of a load aggregator also becomes uncertain in real time. Though there is uncertainties in both load and price, the use of EVs storage capacity can make the operation of load aggregator flexible. LA submits its offer to day-ahead market based on predicted loads and optimized use of its EVs to maximize its profit, as well as in real time operation it uses its energy storage capacity in such a way that it can maximize its profit. In this project, load aggregators profit maximization algorithm is formulated and the optimization problem is solved with the help of CVX. As in real time operation the forecasted loads differ from actual load, the mismatches are settled in real time balancing market. Simulation results compare the profit of a load aggregator with a hypothetical group of 1000 EVs and without EVs.Keywords: CVX, electricity market, load aggregator, load and price uncertainties, profit maximization, real time balancing operation
Procedia PDF Downloads 4162129 Theoretical, Numerical and Experimental Assessment of Elastomeric Bearing Stability
Authors: Manuel A. Guzman, Davide Forcellini, Ricardo Moreno, Diego H. Giraldo
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Elastomeric bearings (EB) are used in many applications, such as base isolation of bridges, seismic protection and vibration control of other structures and machinery. Their versatility is due to their particular behavior since they have different stiffness in the vertical and horizontal directions, allowing to sustain vertical loads and at the same time horizontal displacements. Therefore, vertical, horizontal and bending stiffnesses are important parameters to take into account in the design of EB. In order to acquire a proper design methodology of EB all three, theoretical, finite element analysis and experimental, approaches should be taken into account to assess stability due to different loading states, predict their behavior and consequently their effects on the dynamic response of structures, and understand complex behavior and properties of rubber-like materials respectively. In particular, the recent large-displacement theory on the stability of EB formulated by Forcellini and Kelly is validated with both numerical simulations using the finite element method, and experimental results set at the University of Antioquia in Medellin, Colombia. In this regard, this study reproduces the behavior of EB under compression loads and investigates the stability behavior with the three mentioned points of view.Keywords: elastomeric bearings, experimental tests, numerical simulations, stability, large-displacement theory
Procedia PDF Downloads 4592128 Physicochemical Analysis of Ground Water of Selected Areas of Oji River in Enugu State, Nigeria
Authors: C. Akpagu Francis, V. Nnamani Emmanuel
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Drinking and use of polluted water from ponds, rivers, lakes, etc. for other domestic activities especially by the larger population in the rural areas has been a major source of health problems to man. A study was carried out in two different ponds in Oji River, Enugu State of Nigeria to determine the extent of total dissolved solid (TDS), metals (lead, cadmium, iron, zinc, manganese, calcium), biochemical oxygen demand (BOD). Samples of water were collected from two different ponds at a distance of 510, and 15 metres from the point of entry into the ponds to fetch water. From the results obtained, TDS (751.6Mg/l), turbidity (24ftu), conductivity (1193µs/cm), cadmium (0.008Mg/l) and lead (0.03mg/t) in pond A (PA) were found to have exceeded the WHO standard. Also in pond B (PB) the results shows that TDS (760.30Mg/l), turbidity (26ftu), conductivity (1195µs/cm), cadmium (0.008mg/l) and lead (0.03Mg/l) were also found to have exceeded the WHO standard which makes the two ponds. Water very unsafe for drinking and use in other domestic activities.Keywords: physicochemical, groundwater, Oji River, Nigeria
Procedia PDF Downloads 4612127 A Study on Approximate Controllability of Impulsive Integrodifferential Systems with Non Local Conditions
Authors: Anandhi Santhosh
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In order to describe various real-world problems in physical and engineering sciences subject to abrupt changes at certain instants during the evolution process, impulsive differential equations has been used to describe the system model. In this article, the problem of approximate controllability for nonlinear impulsive integrodifferential equations with state-dependent delay is investigated. We study the approximate controllability for nonlinear impulsive integrodifferential system under the assumption that the corresponding linear control system is approximately controllable. Using methods of functional analysis and semigroup theory, sufficient conditions are formulated and proved. Finally, an example is provided to illustrate the proposed theory.Keywords: approximate controllability, impulsive differential system, fixed point theorem, state-dependent delay
Procedia PDF Downloads 3832126 Combination of Work and Family Demands Correlated with the Severity of Wrist Musculoskeletal Disorders among Nurses
Authors: Hsien Hwa Kuo, Lin Wen Chun, Lin Wen Chun, Hsien Wen Kuo
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Objective: Nurses represent an important occupational group frequently affected by wrist musculoskeletal disorders (WMSDs) due to a heavy workload, working shifts, poor posture, giving shots, making beds, lifting patients, bending their waist and insufficient rest time every day. However, lack of research reported nurses whether workload in household correlated with the severity of WMSDs. Methods: 550 nurses from a hospital in Taoyuan were interviewed using a modified standardized Nordic Musculoskeletal (NMQ) questionnaire including the demographic information, workplace condition and nine body parts of musculoskeletal disorders. Results: 17.9% and 23.9% of severity and symptoms in WMSDs among nurses with children were significant higher than among nurses without children (12.4% and 15.9%). Based on multiple logistic regression models adjusted for age, work duration, job title and body mass index (BMI), we found that heavy workload in hospital had higher odds ratio (OR) of the severity and symptoms of WMSD among nurses with children (OR= 8.67 and OR= 4.30, p<0.05) compared to nurses without children (OR= 1.94 and OR= 1.70). Conclusion: The severity and symptoms of WMSDs among nurses significantly correlated with workload in hospital among nurses with children. If women are at greater risk because of the combination of their work and family demands, synergistic effect of WMSDs was found among nurses. Comment: Women's domestic work, especially once they become mothers, they invest more time and energy caring for children, helping others, and doing housework. Thus domestic work, per se, may be a risk factor for wrist musculoskeletal problems, and, more importantly, it may constrain women's ability to protect themselves from the effects of their paid work. If nurses with more domestic work periodically make efforts to physical activity or modify inappropriate posture, their WMSDs symptoms will be alleviated.Keywords: musculoskeletal disorders, nurse, NMQ, WMSDs
Procedia PDF Downloads 3552125 An Investigation of the Effectiveness and Quality Service of Thai Labor Fund
Authors: Chutikarn Sriviboon
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The objectives of this research were to study the operation of the Labor Fund and to investigate the needs for money and assistance from Thai laborers both from within the system and out of the system and to compare between the assistance from domestic and international funds. The population of this study included three labor groups: group one was laborer in the system who were the members of saving cooperative, group two was laborer in the system who were not the members of saving cooperative, and group three was laborer who were not in the system. This was a mixed research of quantitative and qualitative methods. The findings can be categorized into four parts. First, the labor fund was beneficial to Thai laborers by giving access to government funds but the weakness was found to be poor public relations. Second, the labor funds should extend their assistance to laborer in the system who was not the members of saving cooperative. Third, the comparison between domestic labor funds and international labor funds revealed that there were no international funds which provided assistance the same way as Thai labor funds. Finally, there was a need to improve the management of labor funds and to provide long term assistance to Thai labors.Keywords: effectiveness, quality, labor funds, service
Procedia PDF Downloads 3552124 Design of Structure for a Heavy-Duty Mineral Tow Machine by Evaluating the Dynamic and Static Loads
Authors: M. Akhondizadeh, Mohsen Khajoei, Mojtaba Khajoei
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The purpose of the present work was the design of a towing machine which was decided to be manufactured by Arman Gohar-e-Sirjan company in the Gol-e-Gohar iron ore complex in Iran. The load analysis has been conducted to determine the static and dynamic loads at the critical conditions. The inertial forces due to the velocity increment and road bump have been considered in load evaluation. The form of loading of the present machine is hauling and/or conveying the mineral machines on the mini ramp. Several stages of these forms of loading, from the initial touch of the tow and carried machine to the final position, have been assessed to determine the critical state. The stress analysis has been performed by the ANSYS software. Several geometries for the main load-carrying elements have been analyzed to have the optimum design by the minimum weight of the structure. Finally, a structure with a total weight of 38 tons has been designed with a static load-carrying capacity of 80 tons by considering the 40 tons additional capacity for dynamic effects. The stress analysis for 120 tons load gives the minimum safety factor of 1.18.Keywords: mechanical design, stress analysis, tow structure, dynamic load, static load
Procedia PDF Downloads 1072123 An Experimental Determination of the Limiting Factors Governing the Operation of High-Hydrogen Blends in Domestic Appliances Designed to Burn Natural Gas
Authors: Haiqin Zhou, Robin Irons
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The introduction of hydrogen into local networks may, in many cases, require the initial operation of those systems on natural gas/hydrogen blends, either because of a lack of sufficient hydrogen to allow a 100% conversion or because existing infrastructure imposes limitations on the % hydrogen that can be burned before the end-use technologies are replaced. In many systems, the largest number of end-use technologies are small-scale but numerous appliances used for domestic and industrial heating and cooking. In such a scenario, it is important to understand exactly how much hydrogen can be introduced into these appliances before their performance becomes unacceptable and what imposes that limitation. This study seeks to explore a range of significantly higher hydrogen blends and a broad range of factors that might limit operability or environmental acceptability. We will present tests from a burner designed for space heating and optimized for natural gas as an increasing % of hydrogen blends (increasing from 25%) were burned and explore the range of parameters that might govern the acceptability of operation. These include gaseous emissions (particularly NOx and unburned carbon), temperature, flame length, stability and general operational acceptability. Results will show emissions, Temperature, and flame length as a function of thermal load and percentage of hydrogen in the blend. The relevant application and regulation will ultimately determine the acceptability of these values, so it is important to understand the full operational envelope of the burners in question through the sort of extensive parametric testing we have carried out. The present dataset should represent a useful data source for designers interested in exploring appliance operability. In addition to this, we present data on two factors that may be absolutes in determining allowable hydrogen percentages. The first of these is flame blowback. Our results show that, for our system, the threshold between acceptable and unacceptable performance lies between 60 and 65% mol% hydrogen. Another factor that may limit operation, and which would be important in domestic applications, is the acoustic performance of these burners. We will describe a range of operational conditions in which hydrogen blend burners produce a loud and invasive ‘screech’. It will be important for equipment designers and users to find ways to avoid this or mitigate it if performance is to be deemed acceptable.Keywords: blends, operational, domestic appliances, future system operation.
Procedia PDF Downloads 232122 Designing and Analyzing Sensor and Actuator of a Nano/Micro-System for Fatigue and Fracture Characterization of Nanomaterials
Authors: Mohammad Reza Zamani Kouhpanji
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This paper presents a MEMS/NEMS device for fatigue and fracture characterization of nanomaterials. This device can apply static loads, cyclic loads, and their combinations in nanomechanical experiments. It is based on the electromagnetic force induced between paired parallel wires carrying electrical currents. Using this concept, the actuator and sensor parts of the device were designed and analyzed while considering the practical limitations. Since the PWCC device only uses two wires for actuation part and sensing part, its fabrication process is extremely easier than the available MEMS/NEMS devices. The total gain and phase shift of the MEMS/NEMS device were calculated and investigated. Furthermore, the maximum gain and sensitivity of the MEMS/NEMS device were studied to demonstrate the capability and usability of the device for wide range of nanomaterials samples. This device can be readily integrated into SEM/TEM instruments to provide real time study of the mechanical behaviors of nanomaterials as well as their fatigue and fracture properties, softening or hardening behaviors, and initiation and propagation of nanocracks.Keywords: sensors and actuators, MEMS/NEMS devices, fatigue and fracture nanomechanical testing device, static and cyclic nanomechanical testing device
Procedia PDF Downloads 2972121 The Impact of Foreign Direct Investment on Economic Growth of Ethiopia: Econometrics Cointegration Analysis
Authors: Dejene Gizaw Kidane
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This study examines the impact of foreign direct investment on economic growth of Ethiopia using yearly time-series data for 1974 through 2013. Economic growth is proxies by real per capita gross domestic product and foreign direct investment proxies by the inflow of foreign direct investment. Other control variables such as gross domestic saving, trade, government consumption and inflation has been incorporated. In order to fully account for feedbacks, a vector autoregressive model is utilized. The results show that there is a stable, long-run relationship between foreign direct investment and economic growth. The variance decomposition results show that the main sources of Ethiopia economic growth variations are due largely own shocks. The pairwise Granger causality results show that there is a unidirectional causality that runs from FDI to economic growth of Ethiopia. Hence, the researcher therefore recommends that, FDI facilitate economic growth, so the government has to exert much effort in order to attract more FDI into the country.Keywords: real per capita GDP, FDI, co-integration, VECM, Granger causality
Procedia PDF Downloads 4362120 The Effect of Mgo and Rubber Nanofillers on Electrical Treeing Characteristic of XLPE Based Nanocomposites
Authors: Nur Amira nor Arifin, Tashia Marie Anthony, Mohd Ruzlin Mokhtar, Huzainie Shafi Abd Halim
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Cross-linked polyethylene (XLPE) material is being used as the cable insulation for the past decades due to its higher working temperature of 90 ˚C and some other advantages. However, the use of XLPE as an insulating material for underground distribution cables may have subjected to the unforeseeable weather and uncontrollable environmental condition. These unfavorable condition when combine with high electric field may lead to the initiation and growth of water tree in XLPE insulation. There are several studies on numerous nanofillers incorporate into polymer matrix to hinder the growth of tree propagation. Hence, in this study aims to investigate the effect of MgO and rubber nanofillers at different concentration on the electrical tree of XLPE. The nanofillers and XLPE were mixed and later extruded. After extrusion, the material were then fabricated into the desired shape for experimental purposes. The result shows that the electrical tree propagation of XLPE filled with optimize concentration of nanofillers were much slower compared to pure XLPE. In this paper, the effect of nanofillers towards electrical treeing characteristic will be discussed.Keywords: electrical trees, nanofillers, polymer nanocomposites, XLPE
Procedia PDF Downloads 1392119 An Experimental Investigation of Rehabilitation and Strengthening of Reinforced Concrete T-Beams Under Static Monotonic Increasing Loading
Authors: Salem Alsanusi, Abdulla Alakad
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An experimental investigation to study the behaviour of under flexure reinforced concrete T-Beams. Those Beams were loaded to pre-designated stress levels as percentage of calculated collapse loads. Repairing these beans by either reinforced concrete jacket, or by externally bolted steel plates were utilized. Twelve full scale beams were tested in this experimental program scheme. Eight out of the twelve beams were loaded under different loading levels. Tests were performed for the beams before and after repair with Reinforced Concrete Jacket (RCJ). The applied Load levels were 60%, 77% and 100% of the calculated collapse loads. The remaining four beams were tested before and after repair with Bolted Steel Plate (BSP). Furthermore, out previously mentioned four beams two beams were loaded to the calculated failure load 100% and the remaining two beams were not subjected to any load. The eight beams recorded for the RCJ test were repaired using reinforced concrete jacket. The four beams recorded for the BSP test were all repaired using steel plate at the bottom. All the strengthened beams were gradually loaded until failure occurs. However, in each loading case, the beams behaviour, before and after strengthening, were studied through close inspection of the cracking propagation, and by carrying out an extensive measurement of deformations and strength. The stress-strain curve for reinforcing steel and the failure strains measured in the tests were utilized in the calculation of failure load for the beams before and after strengthening. As a result, the calculated failure loads were close to the actual failure tests in case of beams before repair, ranging from 85% to 90% and also in case of beams repaired by reinforced concrete jacket ranging from 70% to 85%. The results were in case of beams repaired by bolted steel plates ranging from (50% to 85%). It was observed that both jacketing and bolted steel plate methods could effectively restore the full flexure capacity of the damaged beams. However, the reinforced jacket has increased the failure load by about 67%, whereas the bolted steel plates recovered the failure load.Keywords: rehabilitation, strengthening, reinforced concrete, beams deflection, bending stresses
Procedia PDF Downloads 3062118 Double Row Taper Roller Bearing Wheel-end System in Rigid Rear Drive Axle in Heavy Duty SUV Passenger Vehicle
Authors: Mohd Imtiaz S, Saurabh Jain, Pothiraj K.
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In today’s highly competitive passenger vehicle market, comfortable driving experience is one of the key parameters significantly weighed by the customer. Smooth ride and handling of the vehicle with exceptionally reliable wheel end solution is a paramount requirement in passenger Sports Utility Vehicle (SUV) vehicles subjected to challenging terrains and loads with rigid rear drive axle configuration. Traditional wheel-end bearing systems in passenger segment rigid rear drive axle utilizes the semi-floating layout, which imparts vertical bending loads and torsion to the axle shafts. The wheel-end bearing is usually a Single or Double Row Deep-Groove Ball Bearing (DRDGBB) or Double Row Angular Contact Ball Bearing (DRACBB). This solution is cost effective and simple in architecture. However, it lacks effectiveness against the heavy loads subjected to a SUV vehicle, especially the axial trust at high-speed cornering. This paper describes the solution of Double Row Taper Roller Bearing (DRTRB) wheel-end for a SUV vehicle in the rigid rear drive axle and improvement in terms of maximizing its load carrying capacity along with better reliability in terms of axial thrust in high-speed cornering. It describes the advantage of geometry of DRTRB over DRDGBB and DRACBB highlighting contact and load flow. The paper also highlights the vehicle level considerations affecting the B10 life of the bearing system for better selection of the DRTRB wheel-ends systems. This paper also describes real time vehicle level results along with theoretical improvements.Keywords: axial thrust, b10 life, deep-groove ball bearing, taper roller bearing, semi-floating layout.
Procedia PDF Downloads 742117 Characteristics of Domestic Sewage in Small Urban Communities
Authors: Shohreh Azizi, Memory Tekere, Wag Nel
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An evaluation of the characteristics of wastewater generated from small communities was carried out in relation to decentralized approach for domestic sewage treatment plant and design of biological nutrient removal system. The study included the survey of the waste from various individual communities such as a hotel, a residential complex, an office premise, and an educational institute. The results indicate that the concentration of organic pollutant in wastewater from the residential complex is higher than the waste from all the other communities with COD 664 mg/l, BOD 370.2 mg/l and TSS 248.8 mg/l. And the waste water from office premise indicates low organic load with COD428 mg/l, BOD 232mg/l and TSS 157mg/l. The wastewater from residential complex was studied under activated sludge process to evaluate this technology for decentralized wastewater treatment. The Activated sludge process was operated at different 12to 4 hrs hydraulic retention times and the optimum 6 hrs HRT was selected, therefore the average reduction of COD (85.92%) and BOD (91.28 %) was achieved. The issue of sludge recycling, maintenance of biomass concentration and high HRT reactor (10 L) volume are making the system non-practical for smaller communities.Keywords: wastewater, small communities, activated sludge process, decentralized system
Procedia PDF Downloads 3572116 Echinococcus in Eastern Cape Province, South Africa
Authors: C. I. Boshoff, S. Steenkamp-Jonker
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Cystic echinococcosis (CE), caused by Echinococcus granulosus is an important parasitic infection in livestock worldwide, with severe zoonotic potential. It is important to understand the variability of Echinococcus granulosus, as genotype variations may influence lifecycle patterns, development rate, and transmission. Cystic Echinococcus samples were collected from domestic animals in Eastern Cape Province, South Africa. A molecular study was performed on 14 hydatid cysts obtained from caprine, ovine and bovine livers in order to determine the Echinococcus granulosus strain present in these hosts. The sequencing of the mitochondrial cytochrome C oxidase subunit I (coxI) gene of the hydatid cysts produced sequences of 400 bp for each sample analysed. These sequences were aligned with those present in GenBank and a phylogenetic tree was constructed. Based on coxI genotype the isolates could be grouped into E. granulosus sensu stricto. The findings of the study represent a pilot molecular study on Echinococcus from domestic animals undertaken in South Africa.Keywords: Echinococcus granulosus, genotypes, livestock, South Africa
Procedia PDF Downloads 4282115 CO2 Mitigation by Promoting Solar Heating in Housing Sector
Authors: F. Sahnoune, M. Madani, M. Zelmat, M. Belhamel
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Home heating and generation of domestic hot water are nowadays important items of expenditure and energy consumption. These are also a major source of pollution and emission of greenhouse gases (GHG). Algeria, like other countries of the southern shore of the Mediterranean has an enormous solar potential (more than 3000 hours of sunshine/year). This potential can be exploited in reducing GHG emissions and contribute to climate change adaptation. This work presents the environmental impact of introduction of solar heating in an individual house in Algerian climate conditions. For this purpose, we determined energy needs for heating and domestic hot water taking into account the thermic heat losses of the no isolated house. Based on these needs, sizing of the solar system was carried out. To compare the performances of solar and classic systems, we conducted also an economic evaluation what is very important for countries like Algeria where conventional energy is subsidized. The study clearly show that environmental and economic benefits are in favor of solar heating development in particular in countries where the thermal insulation of the building and energy efficiency are poorly developed.Keywords: CO2 mitigation, solar energy, solar heating, environmental impact
Procedia PDF Downloads 3992114 Investigation of Astrocyte Physiology on Stiffness-Controlled Cellulose Acetate Nanofiber as a Tissue Scaffold
Authors: Sun Il Yu, Jung Hyun Joo, Hwa Sung Shin
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Astrocytes are known as dominant cells in CNS and play a role as a supporter of CNS activity and regeneration. Recently, three-dimensional culture of astrocytes were actively applied to understand in vivo astrocyte works. Electrospun nanofibers are attractive for 3D cell culture system because they have a high surface to volume ratio and porous structure, and have already been used for 3D astrocyte cultures. In this research, the stiffness of cellulose acetate (CA) nanofiber was controlled by heat treatment. As stiffness increased, astrocyte cell viability and adhesion increased. Reactivity of astrocyte was also upregulated in stiffer CA nanofiber in terms of GFAP, an intermediate filament protein. Finally, we demonstrated that stiffness-controllable CA is attractive for astrocyte tissue engineering.Keywords: astrocyte, cellulose acetate, nanofiber, tissue scaffold
Procedia PDF Downloads 3552113 Management of Medical Equipment Maintenance
Authors: Gholamreza Madad
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The role of medical equipment in modern advanced hospitals is irrefutable. Despite limited financial resources, developing countries have taken an uncontrollable manner to the purchase of complex and expensive equipment, although they have not taken good maintenance to keep these huge capitals. In our country, limited studies have indicated that the irregularities exist in the management of medical equipment maintenance. Research method: The research was done as a cross-sectional one, and in this study, a questionnaire was used to collect data in 10 hospitals. After distributing and collecting questionnaires in person, the collected data were analyzed using descriptive statistics and SPSS software. Research findings: According to the obtained results from the four dimensions of the management of medical equipment maintenance, only (maintenance planning) was in a moderate position and other components with a score of less than 50% were at a low level. There was a direct relationship between the total score of maintenance management and guidance points and coordination of medical equipment maintenance, and as well as the age of hospital managers. Discussion and conclusion: In sum, we can say that problems such as lack of skilled staff in medical engineering departments of hospitals, lack of funds and unaware of the authorities of medical engineering units to their duties have caused that the maintenance situation of medical equipment maintenance is in poor condition (near average). The low inexperience of the authorities of the unit has also contributed to this problem.Keywords: equipment, maintenance, medical equipment, hospitals
Procedia PDF Downloads 1622112 3D-Printing of Waveguide Terminations: Effect of Material Shape and Structuring on Their Characteristics
Authors: Lana Damaj, Vincent Laur, Azar Maalouf, Alexis Chevalier
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Matched termination is an important part of the passive waveguide components. It is typically used at the end of a waveguide transmission line to prevent reflections and improve signal quality. Waveguide terminations (loads) are commonly used in microwave and RF applications. In traditional microwave architectures, usually, waveguide termination consists of a standard rectangular waveguide made by a lossy resistive material, and ended by shorting metallic plate. These types of terminations are used, to dissipate the energy as heat. However, these terminations may increase the size and the weight of the overall system. New alternative solution consists in developing terminations based on 3D-printing of materials. Designing such terminations is very challenging since it should meet the requirements imposed by the system. These requirements include many parameters such as the absorption, the power handling capability in addition to the cost, the size and the weight that have to be minimized. 3D-printing is a shaping process that enables the production of complex geometries. It allows to find best compromise between requirements. In this paper, a comparison study has been made between different existing and new shapes of waveguide terminations. Indeed, 3D printing of absorbers makes it possible to study not only standard shapes (wedge, pyramid, tongue) but also more complex topologies such as exponential ones. These shapes have been designed and simulated using CST MWS®. The loads have been printed using the carbon-filled PolyLactic Acid, conductive PLA from ProtoPasta. Since the terminations has been characterized in the X-band (from 8GHz to 12GHz), the rectangular waveguide standard WR-90 has been selected. The classical wedge shape has been used as a reference. First, all loads have been simulated with the same length and two parameters have been compared: the absorption level (level of |S11|) and the dissipated power density. This study shows that the concave exponential pyramidal shape has the better absorption level and the convex exponential pyramidal shape has the better dissipated power density level. These two loads have been printed in order to measure their properties. A good agreement between the simulated and measured reflection coefficient has been obtained. Furthermore, a study of material structuring based on the honeycomb hexagonal structure has been investigated in order to vary the effective properties. In the final paper, the detailed methodology and the simulated and measured results will be presented in order to show how 3D-printing can allow controlling mass, weight, absorption level and power behaviour.Keywords: additive manufacturing, electromagnetic composite materials, microwave measurements, passive components, power handling capacity (PHC), 3D-printing
Procedia PDF Downloads 202111 Analyzing Bridge Response to Wind Loads and Optimizing Design for Wind Resistance and Stability
Authors: Abdul Haq
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The goal of this research is to better understand how wind loads affect bridges and develop strategies for designing bridges that are more stable and resistant to wind. The effect of wind on bridges is essential to their safety and functionality, especially in areas that are prone to high wind speeds or violent wind conditions. The study looks at the aerodynamic forces and vibrations caused by wind and how they affect bridge construction. Part of the research method involves first understanding the underlying ideas influencing wind flow near bridges. Computational fluid dynamics (CFD) simulations are used to model and forecast the aerodynamic behaviour of bridges under different wind conditions. These models incorporate several factors, such as wind directionality, wind speed, turbulence intensity, and the influence of nearby structures or topography. The results provide significant new insights into the loads and pressures that wind places on different bridge elements, such as decks, pylons, and connections. Following the determination of the wind loads, the structural response of bridges is assessed. By simulating their dynamic behavior under wind-induced forces, Finite Element Analysis (FEA) is used to model the bridge's component parts. This work contributes to the understanding of which areas are at risk of experiencing excessive stresses, vibrations, or oscillations due to wind excitations. Because the bridge has inherent modes and frequencies, the study considers both static and dynamic responses. Various strategies are examined to maximize the design of bridges to withstand wind. It is possible to alter the bridge's geometry, add aerodynamic components, add dampers or tuned mass dampers to lessen vibrations, and boost structural rigidity. Through an analysis of several design modifications and their effectiveness, the study aims to offer guidelines and recommendations for wind-resistant bridge design. In addition to the numerical simulations and analyses, there are experimental studies. In order to assess the computational models and validate the practicality of proposed design strategies, scaled bridge models are tested in a wind tunnel. These investigations help to improve numerical models and prediction precision by providing valuable information on wind-induced forces, pressures, and flow patterns. Using a combination of numerical models, actual testing, and long-term performance evaluation, the project aims to offer practical insights and recommendations for building wind-resistant bridges that are secure, long-lasting, and comfortable for users.Keywords: wind effects, aerodynamic forces, computational fluid dynamics, finite element analysis
Procedia PDF Downloads 662110 Effects of Inadequate Domestic Water Supply on Human Health in Selected Neighbourhoods of Lokoja, Kogi State
Authors: Folorunsho J. O., Umar M. A.
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Access to potable water supply in both the rural and urban regions of the world has been neglected, and this has severely affected man and the aesthetics of the natural environment of man. This has further worsened the issue of diseases prevalence. This study considered the effects of inadequate domestic water supply on human health in selected neighbourhoods of Lokoja. The study used descriptive statistics such as relative frequencies, percentages and inferential statistics to analyse the data obtained through the use of structured questionnaire. The results revealed that the females and male constituted 56% and 44% of the respondents respectively; 62% of the respondents married and 32% are unmarried; respondents between ages 31 and 40 years constitute majority of the study population, while respondents with tertiary education constituted 35%, and those with secondary education were 32% of the total respondents. Furthermore, civil servants constituted 40% and unemployed 16% of the total respondents. In terms of monthly income, 40% of the respondents was found to earn between ₦31,000 - 40,000 monthly. On the perception of households on the availability and adequacy of domestic water supply, the study revealed that 64.7% of the respondents have pipe-borne water as their main source of water supply, with only 28.5% out of the 64.7% have pipe-borne water supply daily. On the relationship between water supply characteristics and health status among households, the result shows that 76% of the respondents perceived a strong relationship between water supply and health status. Cumulatively, 67% of the respondents confirm that both the quality and quantity of water supplied play a critical role in determining health status of residents of the study area. The respondents also reported skin diseases (96%), diarrhoea (96%), malaria (91%), cholera (67%), dysentery (67%), and respiratory diseases (67%) as the most perceived and experienced in the area, the disease rate in the prevalence order of malaria (81%), diarrhoea (61%), skin diseases (58%), cholera (34%), dysentery (31%) and respiratory disease (14%) respectively. Finally, the results further showed how households cope with inadequate water supply with 52% of the respondents confirm that they regularly treat their water before it was deployed for domestic uses, while 35%, 26%, 25%, 10% and 4% of the 52% respectively, adopted boiling, addition of alums, filtering with fabrics, chlorination and bleaching as the preferred treatment methods. The study thus recommended policy options that will aggressively launch adequate potable water supply infrastructure in the study area.Keywords: Potable Water, Supply, Human Health, Perception, ChlorinationKeywords: potable water, human health, perception, chlorination
Procedia PDF Downloads 652109 The Vicissitudes of Monetary Policy Rates and Macro-Economic Variables in the West African Monetary Zone
Authors: Jonathan Olusegun Famoroti, Mathew Ekundayo Rotimi, Mishelle Doorasamy
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This study offers an empirical investigation into some selected macroeconomic drivers of the monetary policy rate in member countries of the West African Monetary Zone (WAMZ), considering both internal and external variables. We employed Autoregressive Distributed Lag (ARDL) to carry out the investigation between monetary policy and some macroeconomic variables in both the long-run and short-run relationship. The results suggest that the drivers of the policy rate in this zone, in the long run, include, among others, global oil price, exchange rate, inflation rate, and gross domestic product, while in the short run, federal fund rate, trade openness, exchange rate, inflation rate, and gross domestic product are core determinants of the policy rate. Therefore, in order to ensure long-run stability in the policy rate among the members’ states, these drivers should be given closer consideration so that the trajectory for effective structure can be designed and fused into the economic structure and policy frameworks accordingly.Keywords: monetary policy rate, macroeconomic variables, WAMZ, ARDL
Procedia PDF Downloads 652108 Effects of Viscous and Pressure Forces in Vortex and Wake Induced Vibrations
Authors: Ravi Chaithanya Mysa, Abouzar Kaboudian, Boo Cheong Khoo, Rajeev Kumar Jaiman
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Cross-flow vortex-induced vibrations of a circular cylinder are compared with the wake-induced oscillations of the downstream cylinder of a tandem cylinder arrangement. It is known that the synchronization of the frequency of vortex shedding with the natural frequency of the structure leads to large amplitude motions. In the case of tandem cylinders, the large amplitudes of the downstream cylinder found are compared to single cylinder setup. In this work, in the tandem arrangement, the upstream cylinder is fixed and the downstream cylinder is free to oscillate in transverse direction. We show that the wake from the upstream cylinder interacts with the downstream cylinder which influences the response of the coupled system. Extensive numerical experiments have been performed on single cylinder as well as tandem cylinder arrangements in cross-flow. Here, the wake interactions in connection to the forces generated are systematically studied. The ratio of the viscous loads to the pressure loads is found to play a major role in the displacement response of the single and tandem cylinder arrangements, as the viscous forces dissipate the energy.Keywords: circular cylinder, vortex-shedding, VIV, wake-induced, vibrations
Procedia PDF Downloads 3662107 Unconventional Hydrocarbon Management Strategy
Authors: Edi Artono, Budi Tamtomo, Gema Wahyudi Purnama
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The world energy demand increasing extreamly high time by time, including domestic demand. That is impossible to avoid because energy a country demand proportional to surge in the number of residents, economic growth and addition of industrial sector. Domestic Oil and gas conventional reserves depleted naturally while production outcome from reservoir also depleted time to time. In the other hand, new reserve did not discover significantly to replace it all. Many people are investigating to looking for new alternative energy to answer the challenge. There are several option to solve energy fossil needed problem using Unconventional Hydrocarbon. There are four aspects to consider as a management reference in order that Unconventional Hydrocarbon business can work properly, divided to: 1. Legal aspect, 2. Environmental aspect, 3. Technical aspect and 4. Economy aspect. The economic aspect as the key to whether or not a project can be implemented or not in Oil and Gas business scheme, so do Unconventional Hydorcarbon business scheme. The support of regulation are needed to buttress Unconventional Hydorcarbon business grow up and make benefits contribute to Government.Keywords: alternative energy, unconventional hydrocarbon, regulation support, management strategy
Procedia PDF Downloads 3492106 Modification of Polymer Composite Based on Electromagnetic Radiation
Authors: Ananta R. Adhikari
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In today's era, polymer composite utilization has witnessed a significant increase across various fronts of material science advancement. Despite the development of many highly sophisticated technologies aimed at modifying polymer composites, there persists a quest for a technology that is straightforward, energy-efficient, easily controllable, cost-effective, time-saving, and environmentally friendly. Microwave technology has emerged as a major technique in material synthesis and modification due to its unique characteristics such as rapid, selective, uniform heating, and, particularly, direct heating based on molecular interaction. This study will be about the utilization of microwave energy as an alternative technique for material processing. Specifically, we will explore ongoing research conducted in our laboratory, focusing on its applications in the medical field.Keywords: polymer composites, material processing, microstructure, microwave radiation
Procedia PDF Downloads 442105 Segregation of Domestic Solid Waste: An Evidence of Households’ Knowledge, Attitude, Behavior, and Challenges from Manipal, India
Authors: Vidya Pratap, Seena Biju, A. Keshavdev
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The ever-increasing quantity and variety of domestic solid waste pose a major challenge to both households as well as to municipal authorities. In keeping with the Indian Prime Minister’s mission of Swachh Bharat (Clean India), the local municipal administration distributed 2 buckets to each household in a residential colony in Manipal (an educational town in southern India). Households were instructed to segregate their waste into wet and dry waste and keep these buckets at their gate for daily collection. This paper captures the knowledge, attitude, and behavior of 145 households along with the challenges they face in segregating their wastes. Survey representatives self-administered a questionnaire based on 107 variables that gathered demographic details, attitude and behavior constructs, knowledge about waste segregation and method of disposal for organic, recyclable and hazardous wastes. The study used descriptive tools to explore the data. While 95% of the respondents preferred good segregation practices, only 86% of them exhibited such behavior. 88% of the families observed had members who were either graduates or post-graduates whereas only 37% of the families had women who were working. In both attitude and behavior, 63% of the households did not have working women. Also, among those who practiced segregation, 7% were observed to not practice segregation in spite of the lady member being at home (The authors of this study in no way intend to name women as responsible for waste segregation at home; this thought is based on the fact that while in conversation with households, all respondents opined that women lead this activity). The findings of the study are intended to add value to the existing perceptions of the municipality regarding citizen behavior towards policy implementation/improvement. India as a country faces roadblocks at many levels of policy implementation. The findings of this study are meant to contribute/clarify about the Clean India drive.Keywords: attitude, behavior, knowledge, segregation of domestic waste
Procedia PDF Downloads 1702104 Genuine Domestic Change or Fake Compliance: Political Pervasiveness in the Serbian Media
Authors: Aleksandra Dragojlov
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Since the election of Aleksandar Vučić and the Progressives, Serbia has witnessed a slow decline in media freedom, which has been worse than in the 1990s. Although the government adopted a package of three laws in August 2014 to bring the media landscape up to European standards, the implementation of the laws has been limited and marginal, with the progressives engaging in fake compliance. The adoption of the new media strategy for 2020-2025 in 2020 has not led to genuine domestic reform and compliance with EU conditionality. In fact, the EU Commission and journalists’ associations in Serbia have criticised the decline in Serbia’s media freedom citing continued attacks on journalists and indirect political and economic control through advertising and project co-financing, which continue to be features of the Serbian media landscape. In the absence of clear and credible EU conditionality, the decline of media freedom is in the eye of the beholder, where the gap between public engagements with Serbian politicians and the critical stance of progress reports regarding the degradation of the media have enabled Serbian elites to exploit this ambiguity to continue their strategy of fake compliance vis-a-vis rule of law. This study used a mixed methods approach combining both primary and secondary sources with those semi-structured interviews via Zoom, email, and in person with EU and Serbian officials and journalists. Our findings add to the studies where the lack of clear and credible conditionality has allowed Serbia politicians to exploit them in a manner that would suit their own interests, finding new means to retain their control over the media. We argued and concluded that it is this discrepancy between public engagements with Serbia and the progress reports in the area of freedom of expression that has not led to genuine domestic media reforms in Serbia and instead allowed Serbian elites to engage in a strategy of fake and even non-compliance towards media freedom conditionality.Keywords: media freedom, EU conditionality, Serbia, fake compliance, EU integration, Chapter 23, justice and fundamental rights
Procedia PDF Downloads 942103 Landfill Leachate and Settled Domestic Wastewater Co-Treatment Using Activated Carbon in Sequencing Batch Reactors
Authors: Amin Mojiri, Hamidi Abdul Aziz
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Leachate is created while water penetrates through the waste in a landfill, carrying some forms of pollutants. In literature, for treatment of wastewater and leachate, different ways of biological treatment were used. Sequencing batch reactor (SBR) is a kind of biological treatment. This study investigated the co-treatment of landfill leachate and domestic waste water by SBR and powdered activated carbon augmented (PAC) SBR process. The response surface methodology (RSM) and central composite design (CCD) were employed. The independent variables were aeration rate (L/min), contact time (h), and the ratio of leachate to wastewater mixture (%; v/v)). To perform an adequate analysis of the aerobic process, three dependent parameters, i.e. COD, color, and ammonia-nitrogen (NH3-N or NH4-N) were measured as responses. The findings of the study indicated that the PAC-SBR showed a higher performance in elimination of certain pollutants, in comparison with SBR. With the optimal conditions of aeration rate (0.6 L/min), leachate to waste water ratio (20%), and contact time (10.8 h) for the PAC-SBR, the removal efficiencies for color, NH3-N, and COD were 72.8%, 98.5%, and 65.2%, respectively.Keywords: co-treatment, landfill Leachate, wastewater, sequencing batch reactor, activate carbon
Procedia PDF Downloads 4652102 Transient Signal Generator For Fault Indicator Testing
Authors: Mohamed Shaban, Ali Alfallah
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This paper describes an application for testing of a fault indicator but it could be used for other network protection testing. The application is created in the LabVIEW environment and consists of three parts. The first part of the application is determined for transient phenomenon generation and imitates voltage and current transient signal at ground fault originate. The second part allows to set sequences of trend for each current and voltage output signal, up to six trends for each phase. The last part of the application generates harmonic signal with continuously controllable amplitude of current or voltage output signal and phase shift of each signal can be changed there. Further any sub-harmonics and upper harmonics can be added to selected current output signalKeywords: signal generator-fault indicator, harmonic signal generator, voltage output
Procedia PDF Downloads 4942101 Stability Analysis of DC Microgrid with Varying Supercapacitor Operating Voltages
Authors: Annie B. V., Anu A. G., Harikumar R.
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Microgrid (MG) is a self-governing miniature section of the power system. Nowadays the majority of loads and energy storage devices are inherently in DC form. This necessitates a greater scope of research in the various types of energy storage devices in DC microgrids. In a modern power system, DC microgrid is a manageable electric power system usually integrated with renewable energy sources (RESs) and DC loads with the help of power electronic converters. The stability of the DC microgrid mainly depends on the power imbalance. Power imbalance due to the presence of intermittent renewable energy resources (RERs) is supplied by energy storage devices. Battery, supercapacitor, flywheel, etc. are some of the commonly used energy storage devices. Owing to the high energy density provided by the batteries, this type of energy storage system is mainly utilized in all sorts of hybrid energy storage systems. To minimize the stability issues, a Supercapacitor (SC) is usually interfaced with the help of a bidirectional DC/DC converter. SC can exchange power during transient conditions due to its high power density. This paper analyses the stability issues of DC microgrids with hybrid energy storage systems (HESSs) arises from a reduction in SC operating voltage due to self-discharge. The stability of DC microgrid and power management is analyzed with different control strategies.Keywords: DC microgrid, hybrid energy storage system (HESS), power management, small signal modeling, supercapacitor
Procedia PDF Downloads 249