Search results for: connected worker
316 Analysis of SEIG for a Wind Pumping Plant Using Induction Motor
Authors: A. Abbou, H. Mahmoudi, M. Akherraz
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In contrast to conventional generators, self-excited induction generators are found to be most suitable machines for wind energy conversion in remote and windy areas due to many advantages over grid connected machines. This papers presents a Self-Excited Induction Generator (SEIG) driven by wind turbine and supplying an induction motor which is coupled to a centrifugal pump. A method to describe the steady state performance based on nodal analysis is presented. Therefore the advanced knowledge of the minimum excitation capacitor value is required. The effects of variation of excitation capacitance on system and rotor speed under different loading conditions have been analyzed and considered to optimize induction motor pump performances.
Keywords: SEIG, Induction Motor, Centrifugal Pump, capacitance requirements, wind rotor speed.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2316315 Scrum as the Method Supporting the Implementation of Knowledge Management in an Organization
Authors: Andrej Miklošík, Eva Hvizdová, Štefan Žák
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Many companies have switched their processes to project-oriented in the last years. This brings new possibilities and effectiveness not only in the field of external processes connected with the product delivery but also the internal processes as well. However centralized project organization which is based on the role of project manager in the team has proved insufficient in some cases. Agile methods of project organization are trying to solve this problem by bringing new view on the project organization, roles, processes and competences. Scrum is one of these methods which builds on the principles of knowledge management to drive the project to effectiveness from all view angles. Using this method to organize internal and delivery projects helps the organization to create and share knowledge throughout the company. It also supports forming unique competences of individuals and project teams and drives innovations in the company.
Keywords: agile software development, knowledge management, knowledge dissemination, project management, SCRUM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2614314 Avoiding Pin Ball Routing Problem in Network Mobility Hand-Off Management
Authors: M. Dinakaran, P. Balasubramanie
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With the demand of mobility by users, wireless technologies have become the hotspot developing arena. Internet Engineering Task Force (IETF) working group has developed Mobile IP to support node mobility. The concept of node mobility indicates that in spite of the movement of the node, it is still connected to the internet and all the data transactions are preserved. It provides location-independent access to Internet. After the incorporation of host mobility, network mobility has undergone intense research. There are several intricacies faced in the real world implementation of network mobility significantly the problem of nested networks and their consequences. This article is concerned regarding a problem of nested network called pinball route problem and proposes a solution to eliminate the above problem. The proposed mechanism is implemented using NS2 simulation tool and it is found that the proposed mechanism efficiently reduces the overload caused by the pinball route problem.Keywords: Mobile IP, Pinball routing problem, NEMO
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1845313 Forming of Institutional Mechanism of Region's Innovative Development
Authors: Mingaleva Zhanna, Gayfutdinova Oksana, Podgornova Evgenia
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The regional innovative competitiveness is an integrating characteristic of the innovative sphere of the region. It depends on a big variety of different parameters connected with all kinds of economic entities- activities. But management parameters shouldn't be irregular, so in order to avoid it, an institutional system should be formed. This system should carry out strategic management of factors having the greatest influence on the region's innovative development. This article is devoted to different aspects of organization of the region's development institutional mechanism, which is based on management of regional innovative competitiveness parameters. The base of the analysis is innovatively-active Russian regions which were compared according to the level of the innovative competitiveness. After that the most important parameters of successful innovative development of the region were revealed with the help of the correlation-regression analysis. The results of the research could be used for investigation of the region's innovative policy.
Keywords: Regional innovative competitiveness, institutional mechanism, innovative region development, correlation-regression analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1611312 Finite Element Modeling for Clamping Stresses Developed in Hot-Driven Steel Structural Riveted Connections
Authors: Jackeline Kafie-Martinez, Peter B. Keating
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A three-dimensional finite element model is developed to capture the stress field generated in connected plates during the installation of hot-driven rivets. Clamping stress is generated when a steel rivet heated to approximately 1000 °C comes in contact with the material to be fastened at ambient temperature. As the rivet cools, thermal contraction subjects the rivet into tensile stress, while the material being fastened is subjected to compressive stress. Model characteristics and assumptions, as well as steel properties variation with respect to temperature are discussed. The thermal stresses developed around the rivet hole are assessed and reported. Results from the analysis are utilized to detect possible regions for fatigue crack propagation under cyclic loads.
Keywords: Jackeline Kafie-Martinez, Peter B. Keating.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1278311 Validation of Solar PV Inverter Harmonics Behaviour at Different Power Levels in a Test Network
Authors: Wilfred Fritz
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Grid connected solar PV inverters need to be compliant to standard regulations regarding unwanted harmonic generation. This paper gives an introduction to harmonics, solar PV inverter voltage regulation and balancing through compensation and investigates the behaviour of harmonic generation at different power levels. Practical measurements of harmonics and power levels with a power quality data logger were made, on a test network at a university in Germany. The test setup and test results are discussed. The major finding was that between the morning and afternoon load peak windows when the PV inverters operate under low solar insolation and low power levels, more unwanted harmonics are generated. This has a huge impact on the power quality of the grid as well as capital and maintenance costs. The design of a single-tuned harmonic filter towards harmonic mitigation is presented.
Keywords: Harmonics, power quality, pulse width modulation, total harmonic distortion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1843310 Fatigue Properties of Steel Sheets Treated by Nitrooxidation
Authors: M. Maronek, J. Barta, P. Palcek, K. Ulrich
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Low carbon deep drawing steel DC 01 according to EN 10130-91 was nitrooxidized in dissociated ammonia at 580°C/45 min and consequently oxidised at 380°C/5 min in vapour of distilled water. Material after nitrooxidation had 54 % increase of yield point, 34 % increase of strength and 10-times increased resistance to atmospheric corrosion in comparison to the material before nitrooxidation. The microstructure of treated material consisted of thin ε-phase layer connected to layer containing precipitated massive needle shaped Fe4N - γ' nitrides. This layer passed to a diffusion layer consisting of fine irregular shaped Fe16N2 - α'' nitrides regularly dispersed in ferritic matrix. Fatigue properties were examined under bending load with frequency of 20 kHz and sinusoidal symmetric cycle. The results confirmed positive influence of nitrooxidation on fatigue properties as fatigue limit of treated material was double in comparison to untreated material.
Keywords: steel sheet, fatigue, nitrooxidation, S-N diagram
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1722309 Networked Radar System to Increase Safety of Urban Railroad Crossing
Authors: S. Saponara, L. Fanucci, R. Cassettari, P. Ruggiero, M. Righetto
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The paper presents an innovative networked radar system for detection of obstacles in a railway level crossing scenario. This Monitoring System (MS) is able to detect moving or still obstacles within the railway level crossing area automatically, avoiding the need of human presence for surveillance. The MS is also connected to the National Railway Information and Signaling System to communicate in real-time the level crossing status. The architecture is compliant with the highest Safety Integrity Level (SIL4) of the CENELEC standard. The number of radar sensors used is configurable at set-up time and depends on how large the level crossing area can be. At least two sensors are expected and up four can be used for larger areas. The whole processing chain that elaborates the output sensor signals, as well as the communication interface, is fully-digital, was designed in VHDL code and implemented onto a Xilinx Virtex 6.
Keywords: Radar for safe mobility, railroad crossing, railway, transport safety.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3090308 Use of Detectors Technology for Gamma Ray Issued from Radioactive Isotopes and its Impact on Knowledge of Behavior of the Stationary Case of Solid Phase Holdup
Authors: Abbas Ali Mahmood Karwi
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For gamma radiation detection, assemblies having scintillation crystals and a photomultiplier tube, also there is a preamplifier connected to the detector because the signals from photomultiplier tube are of small amplitude. After pre-amplification the signals are sent to the amplifier and then to the multichannel analyser. The multichannel analyser sorts all incoming electrical signals according to their amplitudes and sorts the detected photons in channels covering small energy intervals. The energy range of each channel depends on the gain settings of the multichannel analyser and the high voltage across the photomultiplier tube. The exit spectrum data of the two main isotopes studied ,putting data in biomass program ,process it by Matlab program to get the solid holdup image (solid spherical nuclear fuel)Keywords: Multichannel analyzer, Spectrum, Energies, Fluids holdup, Image
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1732307 Exploitation of Technology by Tshwane Residents for Tourism Development Purposes
Authors: P. P. S. Sifolo, M. J. Maimela M. P. Tladi
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This article investigates technology used by Tshwane residents intended for tourism purposes. The aim is to contribute information for planning and management concerning technology within the tourism sector in the city of Tshwane, South Africa. This study identified the types of tourist related technologies used by the Tshwane residents, be it for business purposes or personal use. The study connected the exploitation of technology for tourism purposes through unpacking the tourism sector as it utilizes technology. Quantitative research methodology was used whereby self-completed questionnaires were chosen as research instruments. The research study carried out a search for knowledge on technology for tourism and the Tshwane residents; however the study revealed that technology has certainly imprinted tourism massively because of its effectiveness and efficiency. Technology has assisted tourism businesses stay abreast of competition with integrated communication technology (ICT) and because of that, SA is on the map as one of the economically performing countries in Africa. Moreover, technology and tourism make a meaningful impact on job creation and Gross Domestic Product (GDP).
Keywords: Information and Communication Technology, Technology for tourism, Tshwane residents.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1921306 Direct Power Control Applied on 5-Level Diode Clamped Inverter Powered by a Renewable Energy Source
Authors: A. Elnady
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This paper presents an improved Direct Power Control (DPC) scheme applied to the multilevel inverter that forms a Distributed Generation Unit (DGU). This paper demonstrates the performance of active and reactive power injected by the DGU to the smart grid. The DPC is traditionally operated by the hysteresis controller with the Space Vector Modulation (SVM) which is applied on the 2-level inverters or 3-level inverters. In this paper, the DPC is operated by the PI controller with the Phase-Disposition Pulse Width Modulation (PD-PWM) applied to the 5-level diode clamped inverter. The new combination of the DPC, PI controller, PD-PWM and multilevel inverter proves that its performance is much better than the conventional hysteresis-SVM based DPC. Simulations results have been presented to validate the performance of the suggested control scheme in the grid-connected mode.
Keywords: Direct power control, PI controller, PD-PWM, and power control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 856305 Heterogeneity-Aware Load Balancing for Multimedia Access over Wireless LAN Hotspots
Authors: Yen-Cheng Chen, Gong-Da Fang
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Wireless LAN (WLAN) access in public hotspot areas becomes popular in the recent years. Since more and more multimedia information is available in the Internet, there is an increasing demand for accessing multimedia information through WLAN hotspots. Currently, the bandwidth offered by an IEEE 802.11 WLAN cannot afford many simultaneous real-time video accesses. A possible way to increase the offered bandwidth in a hotspot is the use of multiple access points (APs). However, a mobile station is usually connected to the WLAN AP with the strongest received signal strength indicator (RSSI). The total consumed bandwidth cannot be fairly allocated among those APs. In this paper, we will propose an effective load-balancing scheme via the support of the IAPP and SNMP in APs. The proposed scheme is an open solution and doesn-t need any changes in both wireless stations and APs. This makes load balancing possible in WLAN hotspots, where a variety of heterogeneous mobile devices are employed.Keywords: Wireless LAN, Load balancing, IAPP, SNMP.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1775304 The Influence of Ancient Artifacts on Contemporary Culture (exemplified by the Painting and Sculpture of Kazakhstan)
Authors: Yerbol B. Kairanov, Arnur Zh. Karymsakov
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Petroglyphs, stone sculptures, burial mounds, and other memorial religious structures are ancient artifacts which find reflection in contemporary world culture, including the culture of Kazakhstan. In this article, the problem of the influence of ancient artifacts on contemporary culture is researched, using as an example Kazakhstan-s sculpture and painting. The practice of creating petroglyphs, stone sculptures, and memorial religious structures was closely connected to all fields of human existence, which fostered the formation of and became an inseparable part of a traditional worldview. The ancient roots of Saka-Sythian and Turkic nomadic culture have been studied, and integrated into the foundations of the contemporary art of Kazakhstan. The study of the ancient cultural heritage of Kazakhstan by contemporary artists, sculptors and architects, as well as the influence of European art and cultures on the art of Kazakhstan are furthering the development of a new national art.Keywords: ancient artifacts, Golden Man, nomadic culture, sculpture, painting
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2465303 Traffic Load based Performance Analysis of DSR and STAR Routing Protocol
Authors: Rani Astya, S.C. Sharma
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The wireless adhoc network is comprised of wireless node which can move freely and are connected among themselves without central infrastructure. Due to the limited transmission range of wireless interfaces, in most cases communication has to be relayed over intermediate nodes. Thus, in such multihop network each node (also called router) is independent, self-reliant and capable to route the messages over the dynamic network topology. Various protocols are reported in this field and it is very difficult to decide the best one. A key issue in deciding which type of routing protocol is best for adhoc networks is the communication overhead incurred by the protocol. In this paper STAR a table driven and DSR on demand protocols based on IEEE 802.11 are analyzed for their performance on different performance measuring metrics versus varying traffic CBR load using QualNet 5.0.2 network simulator.Keywords: Adhoc networks, wireless networks, CBR, routingprotocols, route discovery, simulation, performance evaluation, MAC, IEEE 802.11, STAR, DSR
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1897302 A Micro-Watt Second Order Filter for a Chopper Stabilized MEMS Pressure Sensor Interface
Authors: Arup K. George, Wai Pan Chan, Zhi Hui Kong, Minkyu Je
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This paper describes a low-power second-order filter for a continuous-time chopper stabilized capacitive sensor interface, integrated with a fully differential post-CMOS surface-micromachined MEMS pressure sensor. The circuit uses a single-ended folded-cascode operational amplifier and two GM-C filters connected in cascade. The circuit is realized in a 0.18 μm CMOS process and offers differential to single-ended conversion. The novelty of the scheme is the cascade of two GM-C filters to achieve a second-order filter while minimizing power dissipation. The simulated filter cutoff frequency is 1.14 kHz at common-mode voltage 1.65 V, operating from a 3.3 V supply while dissipating 172μW of power. The filter achieves an operating range of 1V for an output load of 1MOhm and 10pF.Keywords: Chopper Stabilization, MEMS, Pressure Sensors, Low Pass Filter
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2103301 Transient Stability Improvement in Multi-Machine System Using Power System Stabilizer (PSS) and Static Var Compensator (SVC)
Authors: Khoshnaw Khalid Hama Saleh, Ergun Ercelebi
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Increasingly complex modern power systems require stability, especially for transient and small disturbances. Transient stability plays a major role in stability during fault and large disturbance. This paper compares a power system stabilizer (PSS) and static Var compensator (SVC) to improve damping oscillation and enhance transient stability. The effectiveness of a PSS connected to the exciter and/or governor in damping electromechanical oscillations of isolated synchronous generator was tested. The SVC device is a member of the shunt FACTS (flexible alternating current transmission system) family, utilized in power transmission systems. The designed model was tested with a multi-machine system consisting of four machines six bus, using MATLAB/SIMULINK software. The results obtained indicate that SVC solutions are better than PSS.Keywords: FACTS, MATLAB/SIMULINK, multi-machine system, PSS, SVC, transient stability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3380300 Zinc Sulfide Concentrates and Optimization of their Roasting in Fluidezed Bed Reactor
Authors: B.S.Boyanov, M.P.Sandalski, K.I.Ivanov
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The production of glass, ceramic materials and many non-ferrous metals (Zn, Cu, Pb, etc.), ferrous metals (pig iron) and others is connected with the use of a considerable number of initial solid raw materials. Before carrying out the basic technological processes (oxidized roasting, melting, agglomeration, baking) it is necessary to mix and homogenize the raw materials that have different chemical and phase content, granulometry and humidity. For this purpose zinc sulfide concentrates differing in origin are studied for their more complete characteristics using chemical, X-ray diffraction analyses, DTA and TGA as well as Mössbauer spectroscopy. The phases established in most concentrates are: β-ZnS, mZnS.nFeS, FeS2, CuFeS2, PbS, SiO2 (α-quartz). With the help of the developed by us a Web-based information system for a continued period of time different mix proportions from zinc concentrates are calculated and used in practice (roasting in fluidized bed reactor), which have to conform to the technological requirements of the zinc hydrometallurgical technological scheme.
Keywords: fluidized bed reactor, roasting, Web-based information system, zinc concentrates.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3162299 Investigation of Inter Feeder Power Flow Regulator: Load Sharing Mode
Authors: Ahmed Hossam-Eldin, Ahmed Elserougi, Ahmed Massoud, Shehab Ahmed
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The Inter feeder Power Flow Regulator (IFPFR) proposed in this paper consists of several voltage source inverters with common dc bus; each inverter is connected in series with one of different independent distribution feeders in the power system. This paper is concerned with how to transfer power between the feeders for load sharing purpose. The power controller of each inverter injects the power (for sending feeder) or absorbs the power (for receiving feeder) via injecting suitable voltage; this voltage injection is simulated by voltage drop across series virtual impedance, the impedance value is selected to achieve the concept of power exchange between the feeders without perturbing the load voltage magnitude of each feeder. In this paper a new control scheme for load sharing using IFPFR is proposed.Keywords: IFPFR, Load sharing, Power transfer
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1621298 Exploring SSD Suitable Allocation Schemes Incompliance with Workload Patterns
Authors: Jae Young Park, Hwansu Jung, Jong Tae Kim
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In the Solid-State-Drive (SSD) performance, whether the data has been well parallelized is an important factor. SSD parallelization is affected by allocation scheme and it is directly connected to SSD performance. There are dynamic allocation and static allocation in representative allocation schemes. Dynamic allocation is more adaptive in exploiting write operation parallelism, while static allocation is better in read operation parallelism. Therefore, it is hard to select the appropriate allocation scheme when the workload is mixed read and write operations. We simulated conditions on a few mixed data patterns and analyzed the results to help the right choice for better performance. As the results, if data arrival interval is long enough prior operations to be finished and continuous read intensive data environment static allocation is more suitable. Dynamic allocation performs the best on write performance and random data patterns.
Keywords: Dynamic allocation, NAND Flash based SSD, SSD parallelism, static allocation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1993297 Minimization of Switching Losses in Cascaded Multilevel Inverters Using Efficient Sequential Switching Hybrid-Modulation Techniques
Authors: P. Satish Kumar, K. Ramakrishna, Ch. Lokeshwar Reddy, G. Sridhar
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This paper presents two different sequential switching hybrid-modulation strategies and implemented for cascaded multilevel inverters. Hybrid modulation strategies represent the combinations of Fundamental-frequency pulse width modulation (FFPWM) and Multilevel sinusoidal-modulation (MSPWM) strategies, and are designed for performance of the well-known Alternative Phase opposition disposition (APOD), Phase shifted carrier (PSC). The main characteristics of these modulations are the reduction of switching losses with good harmonic performance, balanced power loss dissipation among the devices with in a cell, and among the series-connected cells. The feasibility of these modulations is verified through spectral analysis, power loss analysis and simulation.
Keywords: Cascaded multilevel inverters, hybrid modulation, power loss analysis, pulse width modulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2980296 Authentication in Multi-Hop Wireless Mesh Networks
Authors: Kaleemullah Khan, Muhammmad Akbar
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Wireless Mesh Networks (WMNs) are an emerging technology for last-mile broadband access. In WMNs, similar to ad hoc networks, each user node operates not only as a host but also as a router. User packets are forwarded to and from an Internet-connected gateway in multi-hop fashion. The WMNs can be integrated with other networking technologies i.e. ad hoc networks, to implement a smooth network extension. The meshed topology provides good reliability and scalability, as well as low upfront investments. Despite the recent start-up surge in WMNs, much research remains to be done in standardizing the functional parameters of WMNs to fully exploit their full potential. An edifice of the security concerns of these networks is authentication of a new client joining an integrated ad hoc network and such a scenario will require execution of a multihop authentication technique. Our endeavor in this paper is to introduce a secure authentication technique, with light over-heads that can be conveniently implemented for the ad-hoc nodes forming clients of an integrated WMN, thus facilitating their inter-operability.Keywords: Multi-Hop WMNs, PANA, EAP-TTLS, Authentication, RADIUS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1820295 Advanced Pulse Width Modulation Techniques for Z Source Multi Level Inverter
Authors: B. M. Manjunatha, D. V. Ashok Kumar, M. Vijay Kumar
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This paper proposes five level diode clamped Z source Inverter. The existing PWM techniques used for ZSI are restricted for two level. The two level Z Source Inverter have high harmonic distortions which effects the performance of the grid connected PV system. To improve the performance of the system the number of voltage levels in the output waveform need to be increased. This paper presents comparative analysis of a five level diode clamped Z source Inverter with different carrier based Modified Pulse Width Modulation techniques. The parameters considered for comparison are output voltage, voltage gain, voltage stress across switch and total harmonic distortion when powered by same DC supply. Analytical results are verified using MATLAB.
Keywords: Diode Clamped, Pulse Width Modulation, total harmonic distortion, Z Source Inverter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2357294 Semi-Transparent Dye-Sensitized Solar Panels for Energy Autonomous Greenhouses
Authors: A. Mourtzikou, D. Sygkridou, T. Georgakopoulos, G. Katsagounos, E. Stathatos
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Over 60% highly transparent quasi-solid-state dye-sensitized solar cells (DSSCs) with dimension of 50x50 cm2 were fabricated via inkjet printing process using nanocomposite inks as raw materials and tested under outdoor illumination conditions. The cells were electrically characterized, and their possible application to the shell of greenhouses was also examined. The panel design was in Z-interconnection, where the working electrode was inkjet printed on one conductive glass and the counter electrode on a second glass in a sandwich configuration. Silver current collective fingers were printed on the glasses to make the internal electrical connections. In that case, the adjacent cells were connected in series via silver fingers and finally insulated using a UV curing resin to protect them from the corrosive (I-/I3-) redox couple of the electrolyte.
Keywords: Dye-sensitized solar panels, inkjet printing, quasi-solid-state electrolyte, semi-transparency, scale up.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 794293 Modelling of Composite Steel and Concrete Beam with the Lightweight Concrete Slab
Authors: V. Přivřelová
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Well-designed composite steel and concrete structures highlight the good material properties and lower the deficiencies of steel and concrete, in particular they make use of high tensile strength of steel and high stiffness of concrete. The most common composite steel and concrete structure is a simply supported beam, which concrete slab transferring the slab load to a beam is connected to the steel cross-section. The aim of this paper is to find the most adequate numerical model of a simply supported composite beam with the cross-sectional and material parameters based on the results of a processed parametric study and numerical analysis. The paper also evaluates the suitability of using compact concrete with the lightweight aggregates for composite steel and concrete beams. The most adequate numerical model will be used in the resent future to compare the results of laboratory tests.
Keywords: Composite beams, high-performance concrete, highstrength steel, lightweight concrete slab, modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2519292 Power Allocation in User-Centric Cell-Free Massive MIMO Systems with Limited Fronthaul Capacity
Authors: Siminfar Samakoush Galougah
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In this paper, we study two power allocation problems for an uplink user-centric (UC) cell-free massive multiple-input multiple-output (CF-mMIMO) system. Besides, we assume each access point (AP) is connected to a central processing unit (CPU) via fronthaul link with limited capacity. To efficiently use the fronthaul capacity, two strategies for transmitting signals from APs to the CPU are employed; namely: compress-forward-estimate (CFE), estimate-compress-forward (ECF). The capacity of the aforementioned strategies in user-centric CF-mMIMO are drived. Then, we solved the two power allocation problems with minimum Spectral Efficiency (SE) and sum-SE maximization objectives for ECF and CFE strategies.
Keywords: Cell-free massive MIMO, limited capacity fronthaul, spectral efficiency, power allocation problem.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 72291 A Study on the Power Control of Wind Energy Conversion System
Authors: Mehdi Nafar, Mohammad Reza Mansouri
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The present research presents a direct active and reactive power control (DPC) of a wind energy conversion system (WECS) for the maximum power point tracking (MPPT) based on a doubly fed induction generator (DFIG) connected to electric power grid. The control strategy of the Rotor Side Converter (RSC) is targeted in extracting a maximum of power under fluctuating wind speed. A fuzzy logic speed controller (FLC) has been used to ensure the MPPT. The Grid Side Converter is directed in a way to ensure sinusoidal current in the grid side and a smooth DC voltage. To reduce fluctuations, rotor torque and voltage use of multilevel inverters is a good way to remove the rotor harmony.Keywords: DFIG, power quality improvement, wind energy conversion system, WECS, fuzzy logic, RSC, GSC, inverter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6831290 Effects of Turbulence Penetration on Valve Leakage in Nuclear Reactor Coolant System
Authors: Gupta Rajesh, Paudel Sagar, Sharma Utkarsh, Singh Amit Kumar
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Thermal stratification has drawn much attention because of the malfunctions at various nuclear plants in U.S.A that raised significant safety concerns. The concerns due to this phenomenon relate to thermal stresses in branch pipes connected to the reactor coolant system piping. This stress limits the lifetime of the piping system, and even leading to penetrating cracks. To assess origin of valve damage in the pipeline, it is essential to determine the effect of turbulence penetration on valve leakage; since stratified flow is generally generated by turbulent penetration or valve leakage. As a result, we concluded with the help of coupled fluent-structural analysis that the pipe with less turbulence has less chance of failure there by requiring less maintenance.
Keywords: Reactor coolant system, thermal stratification, turbulent penetration, coupled fluent-structural analysis, Von Mises stress.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1479289 Evaluation Method for Information Security Levels of CIIP (Critical Information Infrastructure Protection)
Authors: Soon-Tai Park, Jong-Whoi Shin, Bog-Ki Min, Ik-Sub Lee, Gang-Shin Lee, Jae-Il Lee
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As the information age matures, major social infrastructures such as communication, finance, military and energy, have become ever more dependent on information communication systems. And since these infrastructures are connected to the Internet, electronic intrusions such as hacking and viruses have become a new security threat. Especially, disturbance or neutralization of a major social infrastructure can result in extensive material damage and social disorder. To address this issue, many nations around the world are researching and developing various techniques and information security policies as a government-wide effort to protect their infrastructures from newly emerging threats. This paper proposes an evaluation method for information security levels of CIIP (Critical Information Infrastructure Protection), which can enhance the security level of critical information infrastructure by checking the current security status and establish security measures accordingly to protect infrastructures effectively.Keywords: Information Security Evaluation Methodology, Critical Information Infrastructure Protection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1783288 Reduction of Differential Column Shortening in Tall Buildings
Authors: Hansoo Kim, Seunghak Shin
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The differential column shortening in tall buildings can be reduced by improving material and structural characteristics of the structural systems. This paper proposes structural methods to reduce differential column shortening in reinforced concrete tall buildings; connecting columns with rigidly jointed horizontal members, using outriggers, and placing additional reinforcement at the columns. The rigidly connected horizontal members including outriggers reduce the differential shortening between adjacent vertical members. The axial stiffness of columns with greater shortening can be effectively increased by placing additional reinforcement at the columns, thus the differential column shortening can be reduced in the design stage. The optimum distribution of additional reinforcement can be determined by applying a gradient based optimization technique.
Keywords: Column shortening, long-term behavior, optimization, tall building.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4011287 3A Distributed Method Algorithm for Exact Side Load Managing Smart Grid Using LABVIEW
Authors: N. Ravi Kumar, R. Kamalakannan
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The advancement of hybrid energy resources such as solar and wind power leading to the emergence of customer owned grid. It provides an opportunity to regulars to obtain low energy costs as well as enabling the power supplier to regulate the utility grid. There is a need to develop smart systems that will automatically submit energy demand schedule and monitors energy price signals in real-time without the prompt of customers. In this paper, a demand side energy management for a grid connected household and also smart preparation of electrical appliance have been presented. It also reduces electricity bill for the consumers in the grid. In addition to this, when production is high, the surplus energy fashioned in the customer owned grid is given to main grid or neighboring micro grids. The simulation of the entire system is presented using LabVIEW software.
Keywords: Distributed renewable energy resource, power storage devices, scheduling, smart meters, smart micro grid, electric vehicle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1093