Search results for: power calculation formulas
6608 The Efficiency of Mechanization in Weed Control in Artificial Regeneration of Oriental Beech (Fagus orientalis Lipsky.)
Authors: Tuğrul Varol, Halil Barış Özel
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In this study which has been conducted in Akçasu Forest Range District of Devrek Forest Directorate; 3 methods (cover removal with human force, cover removal with Hitachi F20 Excavator, and cover removal with agricultural equipment mounted on a Ferguson 240S agriculture tractor) utilized in weed control efforts in regeneration of degraded oriental beech forests have been compared. In this respect, 3 methods have been compared by determining certain work hours and standard durations of unit areas (1 hectare). For this purpose, evaluating the tasks made with human and machine force from the aspects of duration, productivity and costs, it has been aimed to determine the most productive method in accordance with the actual ecological conditions of research field. Within the scope of the study, the time studies have been conducted for 3 methods used in weed control efforts. While carrying out those studies, the performed implementations have been evaluated by dividing them into business stages. Also, the actual data have been used while calculating the cost accounts. In those calculations, the latest formulas and equations which are also used in developed countries have been utilized. The variance of analysis (ANOVA) was used in order to determine whether there is any statistically significant difference among obtained results, and the Duncan test was used for grouping if there is significant difference. According to the measurements and findings carried out within the scope of this study, it has been found during living cover removal efforts in regeneration efforts in demolished oriental beech forests that the removal of weed layer in 1 hectare of field has taken 920 hours with human force, 15.1 hours with excavator and 60 hours with an equipment mounted on a tractor. On the other hand, it has been determined that the cost of removal of living cover in unit area (1 hectare) was 3220.00 TL for man power, 788.70 TL for excavator and 2227.20 TL for equipment mounted on a tractor. According to the obtained results, it has been found that the utilization of excavator in weed control effort in regeneration of degraded oriental beech regions under actual ecological conditions of research field has been found to be more productive from both of aspects of duration and costs. These determinations carried out should be repeated in weed control efforts in degraded forest fields with different ecological conditions, it is compulsory for finding the most efficient weed control method. These findings will light the way of technical staff of forestry directorate in determination of the most effective and economic weed contol method. Thus, the more actual data will be used while preparing the weed control budgets, and there will be significant contributions to national economy. Also the results of this and similar studies are very important for developing the policies for our forestry in short and long term.Keywords: artificial regeneration, weed control, oriental beech, productivity, mechanization, man power, cost analysis
Procedia PDF Downloads 4186607 Wind Power Assessment for Turkey and Evaluation by APLUS Code
Authors: Ibrahim H. Kilic, A. B. Tugrul
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Energy is a fundamental component in economic development and energy consumption is an index of prosperity and the standard of living. The consumption of energy per capita has increased significantly over the last decades, as the standard of living has improved. Turkey’s geographical location has several advantages for extensive use of wind power. Among the renewable sources, Turkey has very high wind energy potential. Information such as installation capacity of wind power plants in installation, under construction and license stages in the country are reported in detail. Some suggestions are presented in order to increase the wind power installation capacity of Turkey. Turkey’s economic and social development has led to a massive increase in demand for electricity over the last decades. Since the Turkey has no major oil or gas reserves, it is highly dependent on energy imports and is exposed to energy insecurity in the future. But Turkey does have huge potential for renewable energy utilization. There has been a huge growth in the construction of wind power plants and small hydropower plants in recent years. To meet the growing energy demand, the Turkish Government has adopted incentives for investments in renewable energy production. Wind energy investments evaluated the impact of feed-in tariffs (FIT) based on three scenarios that are optimistic, realistic and pessimistic with APLUS software that is developed for rational evaluation for energy market. Results of the three scenarios are evaluated in the view of electricity market for Turkey.Keywords: APLUS, energy policy, renewable energy, wind power, Turkey
Procedia PDF Downloads 3036606 A Geometric Interpolation Scheme in Overset Meshes for the Piecewise Linear Interface Calculation Volume of Fluid Method in Multiphase Flows
Authors: Yanni Chang, Dezhi Dai, Albert Y. Tong
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Piecewise linear interface calculation (PLIC) schemes are widely used in the volume-of-fluid (VOF) method to capture interfaces in numerical simulations of multiphase flows. Dynamic overset meshes can be especially useful in applications involving component motions and complex geometric shapes. In the present study, the VOF value of an acceptor cell is evaluated in a geometric way that transfers the fraction field between the meshes precisely with reconstructed interfaces from the corresponding donor elements. The acceptor cell value is evaluated by using a weighted average of its donors for most of the overset interpolation schemes for continuous flow variables. The weighting factors are obtained by different algebraic methods. Unlike the continuous flow variables, the VOF equation is a step function near the interfaces, which ranges from zero to unity rapidly. A geometric interpolation scheme of the VOF field in overset meshes for the PLIC-VOF method has been proposed in the paper. It has been tested successfully in quadrilateral/hexahedral overset meshes by employing several VOF advection tests with imposed solenoidal velocity fields. The proposed algorithm has been shown to yield higher accuracy in mass conservation and interface reconstruction compared with three other algebraic ones.Keywords: interpolation scheme, multiphase flows, overset meshes, PLIC-VOF method
Procedia PDF Downloads 1766605 The Impact of the Constitution of Myanmar on the Political Power of Aung San Suu Kyi and the Rohingya Conflict
Authors: Nur R. Daut
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The objective of this paper is to offer an insight on how political power inequality has contributed and exacerbated the political violence towards the Rohingya ethnic group in Myanmar. In particular, this paper attempts to illustrate how power inequality in the country has prevented Myanmar’s leader Aung San Suu Kyi from taking effective measures on the issue. The research centers on the question of why Aung San Suu Kyi has been seen as not doing enough to stop the persecution of the Rohingya ethnic group ever since she was appointed the State Counsellor to the Myanmar government. As a Nobel Peace Prize laureate, Suu Kyi’s lack of action on the matter has come under severe criticism by the international community. Many have seen this as Suu Kyi’s failure to establish democracy and allowing mass killing to spread in the country. The real question that many perhaps should be asking, however, is how much power Suu Kyi actually holds within the government which is still heavily controlled by the military or Tatmadaw. This paper argues that Suu Kyi’s role within the government is limited which hinders constructive and effective measures to be taken on the Rohingya issue. Political power in this research is being measured by 3 factors: control over events such as burning of Rohingya villages, control over resources such as land ownership and media and control over actors such the Tatmadaw, police force and civil society who are greatly needed to ease and resolve the conflict. In order to illustrate which individuals or institution have control over all the 3 above factors, this paper will first study the constitution of Myanmar. The constitution will also be able to show the asymmetrical power relations as it will provide evidence as to how much political power Suu Kyi holds within the government in comparison to other political actors and institutions. Suu Kyi’s role as a state counsellor akin to a prime minister is a newly created position as the current constitution of Myanmar bars anyone with a foreign spouse from holding the post of a president in the country. This is already an indication of the inequality of political power between Suu Kyi and the military. Apart from studying the constitution of Myanmar, Suu Kyi’s speeches and various interviews are also studied in order to answer the research question. Unfortunately, Suu Kyi’s limited political power also involves the Buddhist monks in Myanmar who have held significant influence throughout the history of the country. This factor further prevents Suu Kyi from preserving the sanctity of human rights in Myanmar.Keywords: Aung San Suu Kyi, constitution of Myanmar, inequality, political power, political violence, Rohingya, Tatmadaw
Procedia PDF Downloads 1166604 Time-Series Load Data Analysis for User Power Profiling
Authors: Mahdi Daghmhehci Firoozjaei, Minchang Kim, Dima Alhadidi
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In this paper, we present a power profiling model for smart grid consumers based on real time load data acquired smart meters. It profiles consumers’ power consumption behaviour using the dynamic time warping (DTW) clustering algorithm. Due to the invariability of signal warping of this algorithm, time-disordered load data can be profiled and consumption features be extracted. Two load types are defined and the related load patterns are extracted for classifying consumption behaviour by DTW. The classification methodology is discussed in detail. To evaluate the performance of the method, we analyze the time-series load data measured by a smart meter in a real case. The results verify the effectiveness of the proposed profiling method with 90.91% true positive rate for load type clustering in the best case.Keywords: power profiling, user privacy, dynamic time warping, smart grid
Procedia PDF Downloads 1516603 Numerical Study of 5kW Vertical Axis Wind Turbine Using DOE Method
Authors: Yan-Ting Lin, Wei-Nian Su
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The purpose of this paper is to demonstrate the design of 5kW vertical axis wind turbine (VAWT) using DOE method. The NACA0015 airfoil was implemented for the design and 3D simulation. The critical design parameters are chord length, tip speed ratio (TSR), aspect ratio (AR) and pitch angle in this investigation. The RNG k-ε turbulent model and the sliding mesh method are adopted in the CFD simulation. The results show that the model with zero pitch, 0.3 m in chord length, TSR of 3, and AR of 10 demonstrated the optimum aerodynamic power under the uniform 10m/s inlet velocity. The aerodynamic power is 3.61kW and 3.89kW under TSR of 3 and 4 respectively. The aerodynamic power decreased dramatically while TSR increased to 5.Keywords: vertical axis wind turbine, CFD, DOE, VAWT
Procedia PDF Downloads 4406602 Genetic Variation of Autosomal STR Loci from Unrelated Individual in Iraq
Authors: H. Imad, Q. Cheah, J. Mohammad, O. Aamera
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The aim of this study is twofold. One is to determine the genetic structure of Iraq population and the second objective of the study was to evaluate the importance of these loci for forensic genetic purposes. FTA® Technology (FTA™ paper DNA extraction) utilized to extract DNA. Twenty STR loci and Amelogenin including D3S1358, D13S317, PentaE, D16S539, D18S51, D2S1338, CSF1PO, Penta D, THO1, vWA, D21S11, D7S820, TPOX, D8S1179, FGA, D2S1338, D5S818, D6S1043, D12S391, D19S433, and Amelogenin amplified by using power plex21® kit. PCR products detected by genetic analyzer 3730xL then data analyzed by PowerStatsV1.2. Based on the allelic frequencies, several statistical parameters of genetic and forensic efficiency have been estimated. This includes the homozygosity and heterozygosity, effective number of alleles (n), the polymorphism information content (PIC), the power of discrimination (DP), and the power of exclusion (PE). The power of discrimination values for all tested loci was from 75% to 96% therefore, those loci can be safely used to establish a DNA-based database for Iraq population.Keywords: autosomal STR, genetic variation, Middle and South of Iraq, statistical parameters
Procedia PDF Downloads 3856601 Electrical Energy Harvesting Using Thermo Electric Generator for Rural Communities in India
Authors: N. Nandan A. M. Nagaraj, L. Sanjeev Kumar
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In the rapidly growing population, the requirement of electrical power is increasing day by day. In order to meet the needs, we need to generate the power using alternate method. In this paper, a presentable approach is developed by analysis and can be implemented by utilizing heat energy, which is generated in numerous ways in some of the rural areas in India. The thermoelectric generator unit will be developed by combing with control circuits and converts, which is used to light the LED lamps. The temperature difference which is available in the kitchens, especially the exhaust pipes/chimneys of wooden fire stoves, where more heat is dissipated into the atmosphere, can be utilized for electrical power generation. Hence, the temperature rise of surroundings atmosphere can be reduced.Keywords: thermo electric generator, LED, converts, temperature
Procedia PDF Downloads 1426600 The Spectral Power Amplification on the Regular Lattices
Authors: Kotbi Lakhdar, Hachi Mostefa
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We show that a simple transformation between the regular lattices (the square, the triangular, and the honeycomb) belonging to the same dimensionality can explain in a natural way the universality of the critical exponents found in phase transitions and critical phenomena. It suffices that the Hamiltonian and the lattice present similar writing forms. In addition, it appears that if a property can be calculated for a given lattice then it can be extrapolated simply to any other lattice belonging to the same dimensionality. In this study, we have restricted ourselves on the spectral power amplification (SPA), we note that the SPA does not have an effect on the critical exponents but does have an effect by the criticality temperature of the lattice; the generalisation to other lattice could be shown according to the containment principle.Keywords: ising model, phase transitions, critical temperature, critical exponent, spectral power amplification
Procedia PDF Downloads 3116599 Unified Power Quality Conditioner Presentation and Dimensioning
Authors: Abderrahmane Kechich, Othmane Abdelkhalek
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Static converters behave as nonlinear loads that inject harmonic currents into the grid and increase the consumption of the inactive power. On the other hand, the increased use of sensitive equipment requires the application of sinusoidal voltages. As a result, the electrical power quality control has become a major concern in the field of power electronics. In this context, the active power conditioner (UPQC) was developed. It combines both serial and parallel structures; the series filter can protect sensitive loads and compensate for voltage disturbances such as voltage harmonics, voltage dips or flicker when the shunt filter compensates for current disturbances such as current harmonics, reactive currents and imbalance. This double feature is that it is one of the most appropriate devices. Calculating parameters is an important step and in the same time it’s not easy for that reason several researchers based on trial and error method for calculating parameters but this method is not easy for beginners researchers especially what about the controller’s parameters, for that reason this paper gives a mathematical way to calculate of almost all of UPQC parameters away from trial and error method. This paper gives also a new approach for calculating of PI regulators parameters for purpose to have a stable UPQC able to compensate for disturbances acting on the waveform of line voltage and load current in order to improve the electrical power quality.Keywords: UPQC, Shunt active filer, series active filer, PI controller, PWM control, dual-loop control
Procedia PDF Downloads 4036598 Low Power Consuming Electromagnetic Actuators for Pulsed Pilot Stages
Authors: M. Honarpardaz, Z. Zhang, J. Derkx, A. Trangärd, J. Larsson
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Pilot stages are one of the most common positioners and regulators in industry. In this paper, we present two novel concepts for pilot stages with low power consumption to regulate a pneumatic device. Pilot 1, first concept, is designed based on a conventional frame core electro-magnetic actuator and a leaf spring to control the air flow and pilot 2 has an axisymmetric actuator and spring made of non-oriented electrical steel. Concepts are simulated in a system modeling tool to study their dynamic behavior. Both concepts are prototyped and tested. Experimental results are comprehensively analyzed and compared. The most promising concept that consumes less than 8 mW is highlighted and presented.Keywords: electro-magnetic actuator, multidisciplinary system, low power consumption, pilot stage
Procedia PDF Downloads 2586597 Developing Soil Accumulation Effect Correction Factor for Solar Photovoltaic Module
Authors: Kelebaone Tsamaase, Rapelang Kemoabe, Japhet Sakala, Edward Rakgati, Ishmael Zibani
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Increasing demand for energy, depletion of non-renewable energy, effects of climate change, the abundance of renewable energy such as solar energy have increased the interest in investing in renewable energies, in particular solar photovoltaic (PV) energy. Solar photovoltaic energy systems as part of clean technology are considered to be environmentally friendly, freely available, offer clean production systems, long term costs benefits as opposed to conventional sources, and are the attractive power source for a wide range of applications in remote areas where there is no easy access to the national grid. To get maximum electrical power, maximum solar power should penetrate the module and be converted accordingly. However, some environmental and other geographical related factors reduce the electrical power. One of them is dust which accumulates on the surface of the module and forming a dust layer and in the process obstructing the solar power from penetrating PV module. This study intends to improve the performance of solar photovoltaic (PV) energy modules by establishing soil accumulation effects correction factor from dust characteristics and properties, and also from dust accumulation and retention pattern on PV module surface. The non-urban dry deposition flux model was adapted to determine monthly and yearly dust accumulation pattern. Consideration was done on prevailing environmental and other geographical conditions. Preliminary results showed that cumulative dust settlement increased during the months of July to October leading to a higher drop in module electrical output power.Keywords: dust, electrical power output, PV module, soil correction factor
Procedia PDF Downloads 1336596 Application of the EU Commission Waste Management Methodology Level(s) to a Construction and a Demolition in North-West Romania.
Authors: Valean Maria
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Construction and demolition waste management is a timely topic, due to the urgency of its transition to sustainability. This sector is responsible for over a third of the waste generated in the E.U., while the legislation requires a proportion of at least 70% preparation for reuse and recycle, excluding backfilling. To this end, the E.U. Commission has provided the Level(s) methodology, allowing for the standardized planning and reporting of waste quantities across all levels of the construction process, from the architecture, to the demolition, from the estimation stage, to the actual measurements at the end of the operations. We applied Level(s) for the first time to the Romanian context, a developing E.U. country in which illegal dumping of contruction waste in nature and landfills, are still common practice. We performed the desk study of the buildings’ documents, followed by field studies of the sites, and finally the insertion and calculation of statistical data of the construction and demolition waste. We learned that Romania is far from the E.U. average in terms of the initial estimations of waste, with some numbers being higher, others lower, and that the price of evacuation to landfills is significantly lower in the developing country, a possible barrier to adopting the new regulations. Finally, we found that concrete is the predominant type waste, in terms of quantity as well as cost of disposal. Further directions of research are provided, such as mapping out all of the alternative facilities in the region and the calculation of the financial costs and of the CO2 footprint, for preparing and delivering waste sustainably, for a more sound and locally adapted model of waste management.Keywords: construction, waste, management, levels, EU
Procedia PDF Downloads 776595 Artificial Neural Network Based Parameter Prediction of Miniaturized Solid Rocket Motor
Authors: Hao Yan, Xiaobing Zhang
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The working mechanism of miniaturized solid rocket motors (SRMs) is not yet fully understood. It is imperative to explore its unique features. However, there are many disadvantages to using common multi-objective evolutionary algorithms (MOEAs) in predicting the parameters of the miniaturized SRM during its conceptual design phase. Initially, the design variables and objectives are constrained in a lumped parameter model (LPM) of this SRM, which leads to local optima in MOEAs. In addition, MOEAs require a large number of calculations due to their population strategy. Although the calculation time for simulating an LPM just once is usually less than that of a CFD simulation, the number of function evaluations (NFEs) is usually large in MOEAs, which makes the total time cost unacceptably long. Moreover, the accuracy of the LPM is relatively low compared to that of a CFD model due to its assumptions. CFD simulations or experiments are required for comparison and verification of the optimal results obtained by MOEAs with an LPM. The conceptual design phase based on MOEAs is a lengthy process, and its results are not precise enough due to the above shortcomings. An artificial neural network (ANN) based parameter prediction is proposed as a way to reduce time costs and improve prediction accuracy. In this method, an ANN is used to build a surrogate model that is trained with a 3D numerical simulation. In design, the original LPM is replaced by a surrogate model. Each case uses the same MOEAs, in which the calculation time of the two models is compared, and their optimization results are compared with 3D simulation results. Using the surrogate model for the parameter prediction process of the miniaturized SRMs results in a significant increase in computational efficiency and an improvement in prediction accuracy. Thus, the ANN-based surrogate model does provide faster and more accurate parameter prediction for an initial design scheme. Moreover, even when the MOEAs converge to local optima, the time cost of the ANN-based surrogate model is much lower than that of the simplified physical model LPM. This means that designers can save a lot of time during code debugging and parameter tuning in a complex design process. Designers can reduce repeated calculation costs and obtain accurate optimal solutions by combining an ANN-based surrogate model with MOEAs.Keywords: artificial neural network, solid rocket motor, multi-objective evolutionary algorithm, surrogate model
Procedia PDF Downloads 906594 Optimal Design of the Power Generation Network in California: Moving towards 100% Renewable Electricity by 2045
Authors: Wennan Long, Yuhao Nie, Yunan Li, Adam Brandt
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To fight against climate change, California government issued the Senate Bill No. 100 (SB-100) in 2018 September, which aims at achieving a target of 100% renewable electricity by the end of 2045. A capacity expansion problem is solved in this case study using a binary quadratic programming model. The optimal locations and capacities of the potential renewable power plants (i.e., solar, wind, biomass, geothermal and hydropower), the phase-out schedule of existing fossil-based (nature gas) power plants and the transmission of electricity across the entire network are determined with the minimal total annualized cost measured by net present value (NPV). The results show that the renewable electricity contribution could increase to 85.9% by 2030 and reach 100% by 2035. Fossil-based power plants will be totally phased out around 2035 and solar and wind will finally become the most dominant renewable energy resource in California electricity mix.Keywords: 100% renewable electricity, California, capacity expansion, mixed integer non-linear programming
Procedia PDF Downloads 1716593 Thermodynamic Cycle Using Cyclopentane for Waste Heat Recovery Power Generation from Clinker Cooler Exhaust Flue Gas
Authors: Vijayakumar Kunche
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Waste heat recovery from Pre Heater exhaust gases and Clinker cooler vent gases is now common place in Cement Industry. Most common practice is to use Steam Rankine cycle for heat to power conversion. In this process, waste heat from the flue gas is recovered through a Heat Recovery steam generator where steam is generated and fed to a conventional Steam turbine generator. However steam Rankine cycle tends to have lesser efficiency for smaller power plants with less than 5MW capacity and where the steam temperature at the inlet of the turbine is less than 350 deg C. further a steam Rankine cycle needs treated water and maintenance intensive. These problems can be overcome by using Thermodynamic cycle using Cyclopentane vapour in place of steam. This innovative cycle is best suited for Heat recovery in cement plants and results in best possible heat to power conversion efficiency. This paper discusses about Heat Recovery Power generation using innovative thermal cycle which uses Cyclopentane vapour in place of water- steam. And how this technology has been adopted for a Clinker cooler hot gas from mid-tap.Keywords: clinker cooler, energy efficiency, organic rankine cycle, waste heat recovery
Procedia PDF Downloads 2366592 Knowledge, Technology and Empowerment in Contemporary Scenario
Authors: Samir Roy
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This paper investigates the relationship among knowledge, technology, and empowerment. In Physics power is defined as rate of doing work. In everyday use, the meaning of the word power is related to the capacity to bring change of value in the world. It appears that the popular aphorism “Knowledge is power” should be revisited in the context of contemporary states of affairs. For instance, classical mechanics is a system of knowledge, so also thermodynamics. But neither of them, per se, is sufficient to produce automobilin es. Boolean algebra, the logical foundation of digital electronic computers, was introduced by George Boole in 1847. But that knowledge was practically useless for almost one hundred years until digital electronics was developed in early twentieth century, which eventually led to invention of digital electronic computers. Empowerment of women is a burning issue in the arena of social justice. However, if we carefully analyze the functional elements of women’s empowerment, we find them to be highly technology driven as well as technology dependent in real life. On the other hand, technology has empowered modern states to maintain social order and promote democracy in an effective manner. This paper includes a few case studies to establish the close correspondence between knowledge, especially scientific knowledge, technology, and empowerment. It appears that in contemporary scenario, “Technology is power” is a more appropriate statement than the traditional aphorism “Knowledge is power”.Keywords: knowledge, science, technology, empowerment, change, social justice
Procedia PDF Downloads 426591 Application of Bim Model Data to Estimate ROI for Robots and Automation in Construction Projects
Authors: Brian Romansky
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There are many practical, commercially available robots and semi-autonomous systems that are currently available for use in a wide variety of construction tasks. Adoption of these technologies has the potential to reduce the time and cost to deliver a project, reduce variability and risk in delivery time, increase quality, and improve safety on the job site. These benefits come with a cost for equipment rental or contract fees, access to specialists to configure the system, and time needed for set-up and support of the machines while in use. Calculation of the net ROI (Return on Investment) requires detailed information about the geometry of the site, the volume of work to be done, the overall project schedule, as well as data on the capabilities and past performance of available robotic systems. Assembling the required data and comparing the ROI for several options is complex and tedious. Many project managers will only consider the use of a robot in targeted applications where the benefits are obvious, resulting in low levels of adoption of automation in the construction industry. This work demonstrates how data already resident in many BIM (Building Information Model) projects can be used to automate ROI estimation for a sample set of commercially available construction robots. Calculations account for set-up and operating time along with scheduling support tasks required while the automated technology is in use. Configuration parameters allow for prioritization of time, cost, or safety as the primary benefit of the technology. A path toward integration and use of automatic ROI calculation with a database of available robots in a BIM platform is described.Keywords: automation, BIM, robot, ROI.
Procedia PDF Downloads 876590 Radio Frequency Energy Harvesting Friendly Self-Clocked Digital Low Drop-Out for System-On-Chip Internet of Things
Authors: Christos Konstantopoulos, Thomas Ussmueller
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Digital low drop-out regulators, in contrast to analog counterparts, provide an architecture of sub-1 V regulation with low power consumption, high power efficiency, and system integration. Towards an optimized integration in the ultra-low-power system-on-chip Internet of Things architecture that is operated through a radio frequency energy harvesting scheme, the D-LDO regulator should constitute the main regulator that operates the master-clock and rest loads of the SoC. In this context, we present a D-LDO with linear search coarse regulation and asynchronous fine regulation, which incorporates an in-regulator clock generation unit that provides an autonomous, self-start-up, and power-efficient D-LDO design. In contrast to contemporary D-LDO designs that employ ring-oscillator architecture which start-up time is dependent on the frequency, this work presents a fast start-up burst oscillator based on a high-gain stage with wake-up time independent of coarse regulation frequency. The design is implemented in a 55-nm Global Foundries CMOS process. With the purpose to validate the self-start-up capability of the presented D-LDO in the presence of ultra-low input power, an on-chip test-bench with an RF rectifier is implemented as well, which provides the RF to DC operation and feeds the D-LDO. Power efficiency and load regulation curves of the D-LDO are presented as extracted from the RF to regulated DC operation. The D-LDO regulator presents 83.6 % power efficiency during the RF to DC operation with a 3.65 uA load current and voltage regulator referred input power of -27 dBm. It succeeds 486 nA maximum quiescent current with CL 75 pF, the maximum current efficiency of 99.2%, and 1.16x power efficiency improvement compared to analog voltage regulator counterpart oriented to SoC IoT loads. Complementary, the transient performance of the D-LDO is evaluated under the transient droop test, and the achieved figure-of-merit is compared with state-of-art implementations.Keywords: D-LDO, Internet of Things, RF energy harvesting, voltage regulators
Procedia PDF Downloads 1456589 Software-Defined Networks in Utility Power Networks
Authors: Ava Salmanpour, Hanieh Saeedi, Payam Rouhi, Elahe Hamzeil, Shima Alimohammadi, Siamak Hossein Khalaj, Mohammad Asadian
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Software-defined network (SDN) is a network architecture designed to control network using software application in a central manner. This ability enables remote control of the whole network regardless of the network technology. In fact, in this architecture network intelligence is separated from physical infrastructure, it means that required network components can be implemented virtually using software applications. Today, power networks are characterized by a high range of complexity with a large number of intelligent devices, processing both huge amounts of data and important information. Therefore, reliable and secure communication networks are required. SDNs are the best choice to meet this issue. In this paper, SDN networks capabilities and characteristics will be reviewed and different basic controllers will be compared. The importance of using SDNs to escalate efficiency and reliability in utility power networks is going to be discussed and the comparison between the SDN-based power networks and traditional networks will be explained.Keywords: software-defined network, SDNs, utility network, open flow, communication, gas and electricity, controller
Procedia PDF Downloads 1136588 Differentiation of the Functional in an Optimization Problem for Coefficients of Elliptic Equations with Unbounded Nonlinearity
Authors: Aigul Manapova
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We consider an optimal control problem in the higher coefficient of nonlinear equations with a divergent elliptic operator and unbounded nonlinearity, and the Dirichlet boundary condition. The conditions imposed on the coefficients of the state equation are assumed to hold only in a small neighborhood of the exact solution to the original problem. This assumption suggests that the state equation involves nonlinearities of unlimited growth and considerably expands the class of admissible functions as solutions of the state equation. We obtain formulas for the first partial derivatives of the objective functional with respect to the control functions. To calculate the gradients the numerical solutions of the state and adjoint problems are used. We also prove that the gradient of the cost function is Lipchitz continuous.Keywords: cost functional, differentiability, divergent elliptic operator, optimal control, unbounded nonlinearity
Procedia PDF Downloads 1726587 Optimal Capacitor Placement in Distribution Systems
Authors: Sana Ansari, Sirus Mohammadi
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In distribution systems, shunt capacitors are used to reduce power losses, to improve voltage profile, and to increase the maximum flow through cables and transformers. This paper presents a new method to determine the optimal locations and economical sizing of fixed and/or switched shunt capacitors with a view to power losses reduction and voltage stability enhancement. General Algebraic Modeling System (GAMS) has been used to solve the maximization modules using the MINOS optimization software with Linear Programming (LP). The proposed method is tested on 33 node distribution system and the results show that the algorithm suitable for practical implementation on real systems with any size.Keywords: power losses, voltage stability, radial distribution systems, capacitor
Procedia PDF Downloads 6476586 Residual Power Series Method for System of Volterra Integro-Differential Equations
Authors: Zuhier Altawallbeh
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This paper investigates the approximate analytical solutions of general form of Volterra integro-differential equations system by using the residual power series method (for short RPSM). The proposed method produces the solutions in terms of convergent series requires no linearization or small perturbation and reproduces the exact solution when the solution is polynomial. Some examples are given to demonstrate the simplicity and efficiency of the proposed method. Comparisons with the Laplace decomposition algorithm verify that the new method is very effective and convenient for solving system of pantograph equations.Keywords: integro-differential equation, pantograph equations, system of initial value problems, residual power series method
Procedia PDF Downloads 4186585 Optimal Placement of the Unified Power Controller to Improve the Power System Restoration
Authors: Mohammad Reza Esmaili
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One of the most important parts of the restoration process of a power network is the synchronizing of its subsystems. In this situation, the biggest concern of the system operators will be the reduction of the standing phase angle (SPA) between the endpoints of the two islands. In this regard, the system operators perform various actions and maneuvers so that the synchronization operation of the subsystems is successfully carried out and the system finally reaches acceptable stability. The most common of these actions include load control, generation control and, in some cases, changing the network topology. Although these maneuvers are simple and common, due to the weak network and extreme load changes, the restoration will be associated with low speed. One of the best ways to control the SPA is to use FACTS devices. By applying a soft control signal, these tools can reduce the SPA between two subsystems with more speed and accuracy, and the synchronization process can be done in less time. Meanwhile, the unified power controller (UPFC), a series-parallel compensator device with the change of transmission line power and proper adjustment of the phase angle, will be the proposed option in order to realize the subject of this research. Therefore, with the optimal placement of UPFC in a power system, in addition to improving the normal conditions of the system, it is expected to be effective in reducing the SPA during power system restoration. Therefore, the presented paper provides an optimal structure to coordinate the three problems of improving the division of subsystems, reducing the SPA and optimal power flow with the aim of determining the optimal location of UPFC and optimal subsystems. The proposed objective functions in this paper include maximizing the quality of the subsystems, reducing the SPA at the endpoints of the subsystems, and reducing the losses of the power system. Since there will be a possibility of creating contradictions in the simultaneous optimization of the proposed objective functions, the structure of the proposed optimization problem is introduced as a non-linear multi-objective problem, and the Pareto optimization method is used to solve it. The innovative technique proposed to implement the optimization process of the mentioned problem is an optimization algorithm called the water cycle (WCA). To evaluate the proposed method, the IEEE 39 bus power system will be used.Keywords: UPFC, SPA, water cycle algorithm, multi-objective problem, pareto
Procedia PDF Downloads 666584 Optimal Tuning of RST Controller Using PSO Optimization for Synchronous Generator Based Wind Turbine under Three-Phase Voltage Dips
Authors: K. Tahir, C. Belfedal, T. Allaoui, C. Gerard, M. Doumi
Abstract:
In this paper, we presented an optimized RST controller using Particle Swarm Optimization (PSO) meta-heuristic technique of the active and reactive power regulation of a grid connected wind turbine based on a wound field synchronous generator. This regulation is achieved below the synchronous speed, by means of a maximum power point tracking algorithm. The control of our system is tested under typical wind variations and parameters variation, fault grid condition by simulation. Some results are presented and discussed to prove simplicity and efficiency of the WRSG control for WECS. On the other hand, according to simulation results, variable speed driven WRSG is not significantly impacted in fault conditions.Keywords: wind energy, particle swarm optimization, wound rotor synchronous generator, power control, RST controller, maximum power point tracking
Procedia PDF Downloads 4516583 Electronic Structure Calculation of AsSiTeB/SiAsBTe Nanostructures Using Density Functional Theory
Authors: Ankit Kargeti, Ravikant Shrivastav, Tabish Rasheed
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The electronic structure calculation for the nanoclusters of AsSiTeB/SiAsBTe quaternary semiconductor alloy belonging to the III-V Group elements was performed. Motivation for this research work was to look for accurate electronic and geometric data of small nanoclusters of AsSiTeB/SiAsBTe in the gaseous form. The two clusters, one in the linear form and the other in the bent form, were studied under the framework of Density Functional Theory (DFT) using the B3LYP functional and LANL2DZ basis set with the software packaged Gaussian 16. We have discussed the Optimized Energy, Frontier Orbital Energy Gap in terms of HOMO-LUMO, Dipole Moment, Ionization Potential, Electron Affinity, Binding Energy, Embedding Energy, Density of States (DoS) spectrum for both structures. The important findings of the predicted nanostructures are that these structures have wide band gap energy, where linear structure has band gap energy (Eg) value is 2.375 eV and bent structure (Eg) value is 2.778 eV. Therefore, these structures can be utilized as wide band gap semiconductors. These structures have high electron affinity value of 4.259 eV for the linear structure and electron affinity value of 3.387 eV for the bent structure form. It shows that electron acceptor capability is high for both forms. The widely known application of these compounds is in the light emitting diodes due to their wide band gap nature.Keywords: density functional theory, DFT, density functional theory, nanostructures, HOMO-LUMO, density of states
Procedia PDF Downloads 1146582 The Impact of Reducing Road Traffic Speed in London on Noise Levels: A Comparative Study of Field Measurement and Theoretical Calculation
Authors: Jessica Cecchinelli, Amer Ali
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The continuing growth in road traffic and the resultant impact on the level of pollution and safety especially in urban areas have led local and national authorities to reduce traffic speed and flow in major towns and cities. Various boroughs of London have recently reduced the in-city speed limit from 30mph to 20mph mainly to calm traffic, improve safety and reduce noise and vibration. This paper reports the detailed field measurements using noise sensor and analyser and the corresponding theoretical calculations and analysis of the noise levels on a number of roads in the central London Borough of Camden where speed limit was reduced from 30mph to 20mph in all roads except the major routes of the ‘Transport for London (TfL)’. The measurements, which included the key noise levels and scales at residential streets and main roads, were conducted during weekdays and weekends normal and rush hours. The theoretical calculations were done according to the UK procedure ‘Calculation of Road Traffic Noise 1988’ and with conversion to the European L-day, L-evening, L-night, and L-den and other important levels. The current study also includes comparable data and analysis from previously measured noise in the Borough of Camden and other boroughs of central London. Classified traffic flow and speed on the roads concerned were observed and used in the calculation part of the study. Relevant data and description of the weather condition are reported. The paper also reports a field survey in the form of face-to-face interview questionnaires, which was carried out in parallel with the field measurement of noise, in order to ascertain the opinions and views of local residents and workers in the reduced speed zones of 20mph. The main findings are that the reduction in speed had reduced the noise pollution on the studied zones and that the measured and calculated noise levels for each speed zone are closely matched. Among the other findings was that of the field survey of the opinions and views of the local residents and workers in the reduced speed 20mph zones who supported the scheme and felt that it had improved the quality of life in their areas giving a sense of calmness and safety particularly for families with children, the elderly, and encouraged pedestrians and cyclists. The key conclusions are that lowering the speed limit in built-up areas would not just reduce the number of serious accidents but it would also reduce the noise pollution and promote clean modes of transport particularly walking and cycling. The details of the site observations and the corresponding calculations together with critical comparative analysis and relevant conclusions will be reported in the full version of the paper.Keywords: noise calculation, noise field measurement, road traffic noise, speed limit in london, survey of people satisfaction
Procedia PDF Downloads 4246581 A Comprehensive Approach in Calculating the Impact of the Ground on Radiated Electromagnetic Fields Due to Lightning
Authors: Lahcene Boukelkoul
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The influence of finite ground conductivity is of great importance in calculating the induced voltages from the radiated electromagnetic fields due to lightning. In this paper, we try to give a comprehensive approach to calculate the impact of the ground on the radiated electromagnetic fields to lightning. The vertical component of lightning electric field is calculated with a reasonable approximation assuming a perfectly conducting ground in case the observation point does not exceed a few kilometres from the lightning channel. However, for distant observation points the radiated vertical component of lightning electric field is attenuated due finitely conducting ground. The attenuation is calculated using the expression elaborated for both low and high frequencies. The horizontal component of the electric field, however, is more affected by a finite conductivity of a ground. Besides, the contribution of the horizontal component of the electric field, to induced voltages on an overhead transmission line, is greater than that of the vertical component. Therefore, the calculation of the horizontal electric field is great concern for the simulation of lightning-induced voltages. For field to transmission lines coupling the ground impedance is calculated for early time behaviour and for low frequency range.Keywords: power engineering, radiated electromagnetic fields, lightning-induced voltages, lightning electric field
Procedia PDF Downloads 4056580 Strategy of Balancing in Russian Energy Diplomacy toward Middle East
Authors: Davood Karimipour
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Since long ago, Russia has been one of the most influential actors in regional equations in South West Asia. The geographic affinity of its vital interests with Western Asia has caused Moscow to have a high sensitivity to the balance of power in the Middle East, as its role in the Syrian crisis clearly demonstrated the importance. In recent years, Moscow has tried to use the energy diplomacy tool in maintaining the balance of power between the major powers in the region. The paper, based on the qualitative case study method, investigates how Russia’s energy diplomacy plays a role in the balance of regional forces in the Middle East, studying the country’s conduct towards Iran, Saudi Arabia, Turkey, and Israel. The hypothesis presented that Russia, using energy tools, is trying to push the regional powers toward cooperation in order to increase the influence in the region, increase power in global markets, and controlling the US to restore power balance in the region. Its cooperation in the Iranian gas industry, the country’s relations with Saudis in the framework of OPEC, cooperation with the Turkish Kurds and the presence in the Israeli gas industry are an example of these Russian energy diplomacy initiatives in West Asia, which is the common point of the Moscow approach to South West Asia.Keywords: Russia, balance of power, energy diplomacy, Middle East
Procedia PDF Downloads 1656579 Comparison between Deterministic and Probabilistic Stability Analysis, Featuring Consequent Risk Assessment
Authors: Isabela Moreira Queiroz
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Slope stability analyses are largely carried out by deterministic methods and evaluated through a single security factor. Although it is known that the geotechnical parameters can present great dispersal, such analyses are considered fixed and known. The probabilistic methods, in turn, incorporate the variability of input key parameters (random variables), resulting in a range of values of safety factors, thus enabling the determination of the probability of failure, which is an essential parameter in the calculation of the risk (probability multiplied by the consequence of the event). Among the probabilistic methods, there are three frequently used methods in geotechnical society: FOSM (First-Order, Second-Moment), Rosenblueth (Point Estimates) and Monte Carlo. This paper presents a comparison between the results from deterministic and probabilistic analyses (FOSM method, Monte Carlo and Rosenblueth) applied to a hypothetical slope. The end was held to evaluate the behavior of the slope and consequent risk analysis, which is used to calculate the risk and analyze their mitigation and control solutions. It can be observed that the results obtained by the three probabilistic methods were quite close. It should be noticed that the calculation of the risk makes it possible to list the priority to the implementation of mitigation measures. Therefore, it is recommended to do a good assessment of the geological-geotechnical model incorporating the uncertainty in viability, design, construction, operation and closure by means of risk management.Keywords: probabilistic methods, risk assessment, risk management, slope stability
Procedia PDF Downloads 392