Search results for: the central pattern generator (CPG)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5626

Search results for: the central pattern generator (CPG)

5446 A CFD Study of the Performance Characteristics of Vented Cylinders as Vortex Generators

Authors: R. Kishan, R. M. Sumant, S. Suhas, Arun Mahalingam

Abstract:

This paper mainly researched on influence of vortex generator on lift coefficient and drag coefficient, when vortex generator is mounted on a flat plate. Vented cylinders were used as vortex generators which intensify vortex shedding in the wake of the vented cylinder as compared to base line circular cylinder which ensures more attached flow and increases lift force of the system. Firstly vented cylinders were analyzed in commercial CFD software which is compared with baseline cylinders for different angles of attack and further variation of lift and drag forces were studied by varying Reynolds number to account for influence of turbulence and boundary layer in the flow. Later vented cylinders were mounted on a flat plate and variation of lift and drag coefficients was studied by varying angles of attack and studying the dependence of Reynolds number and dimensions of vortex generator on the coefficients. Mesh grid sensitivity is studied to check the convergence of the results obtained It was found that usage of vented cylinders as vortex generators increased lift forces with small variation in drag forces by varying angle of attack.

Keywords: CFD analysis, drag coefficient, FVM, lift coefficient, modeling, Reynolds number, simulation, vortex generators, vortex shedding

Procedia PDF Downloads 406
5445 The Design of PFM Mode DC-DC Converter with DT-CMOS Switch

Authors: Jae-Chang Kwak, Yong-Seo Koo

Abstract:

The high efficiency power management IC (PMIC) with switching device is presented in this paper. PMIC is controlled with PFM control method in order to have high power efficiency at high current level. Dynamic Threshold voltage CMOS (DT-CMOS) with low on-resistance is designed to decrease conduction loss. The threshold voltage of DT-CMOS drops as the gate voltage increase, resulting in a much higher current handling capability than standard MOSFET. PFM control circuits consist of a generator, AND gate and comparator. The generator is made to have 1.2MHz oscillation voltage. The DC-DC converter based on PFM control circuit and low on-resistance switching device is presented in this paper.

Keywords: DT-CMOS, PMIC, PFM, DC-DC converter

Procedia PDF Downloads 427
5444 Sliding Mode Control of the Power of Doubly Fed Induction Generator for Variable Speed Wind Energy Conversion System

Authors: Ahmed Abbou, Ali Mousmi, Rachid El Akhrif

Abstract:

This research paper aims to reduce the chattering phenomenon due to control by sliding mode control applied on a wind energy conversion system based on the doubly fed induction generator (DFIG). Our goal is to offset the effect of parametric uncertainties and come as close as possible to the dynamic response solicited by the control law in the ideal case and therefore force the active and reactive power generated by the DFIG to accurately follow the reference values which are provided to it. The simulation results using Matlab / Simulink demonstrate the efficiency and performance of the proposed technique while maintaining the simplicity of control by first order sliding mode.

Keywords: correction of the equivalent command, DFIG, induction machine, sliding mode controller

Procedia PDF Downloads 388
5443 The Relationship among Attachment Styles, Humor Styles and Communication Patterns in Female Married Students

Authors: Elham Fathi, Seyed Mohammad Kalantarkousheh, Abolfazl Hatami Varzane

Abstract:

The present study aimed to determine predict capacity of the relationship among attachment styles, humor styles and communication patterns in female married students. Statistical population consisted of female married students from Allameh Tabataba’i University. The research sample consisted of 104 married students selected through convenience sampling. They responded to study instruments that consisted of attachment styles, humor styles and Communication patterns questionnaires. Data was analyzed by means of correlation method. The results indicated significant positive relationship between secure attachment styles with adaptive humor styles, and anxious attachment styles with maladaptive humor styles. Also a negative relationship between avoidant attachment with affiliative humor, and anxious attachment with self-enhancing humor was found. Furthermore, a negative relationship between self- enhancing humor styles with demand – withdraw communication pattern, and between affiliative humor with mutual avoidant communication pattern and a positive relationship between affiliative humor with mutual constructive communication pattern was observed. The relationship between secure attachment with mutual constructive communication pattern was positive, while relationship between avoidant attachment to mutual constructive communication pattern was negative and significant and its relation with mutual avoidant communication pattern was significantly positive. The result of regression analysis indicated that affliative humor style and secure attachment style, positively predicted mutual constructive communication pattern. Avoidant attachment style positively and affliative humor style negatively predicted the mutual avoidant communication pattern. And self-enhancing humor style negatively predicted the demand – withdraw communication pattern style.

Keywords: attachment styles, communication patterns, humor styles, female married students

Procedia PDF Downloads 349
5442 Hyperchaos-Based Video Encryption for Device-To-Device Communications

Authors: Samir Benzegane, Said Sadoudi, Mustapha Djeddou

Abstract:

In this paper, we present a software development of video streaming encryption for Device-to-Device (D2D) communications by using Hyperchaos-based Random Number Generator (HRNG) implemented in C#. The software implements and uses the proposed HRNG to generate key stream for encrypting and decrypting real-time video data. The used HRNG consists of Hyperchaos Lorenz system which produces four signal outputs taken as encryption keys. The generated keys are characterized by high quality randomness which is confirmed by passing standard NIST statistical tests. Security analysis of the proposed encryption scheme confirms its robustness against different attacks.

Keywords: hyperchaos Lorenz system, hyperchaos-based random number generator, D2D communications, C#

Procedia PDF Downloads 341
5441 Thermodynamic Analysis of an Ejector-Absorption Refrigeration Cycle with Using NH3-H2O

Authors: Samad Jafarmadar, Amin Habibzadeh, Mohammad Mehdi Rashidi, Sayed Sina Rezaei, Abbas Aghagoli

Abstract:

In this paper, the ejector-absorption refrigeration cycle is presented. This article deals with the thermodynamic simulation and the first and second law analysis of an ammonia-water. The effects of parameters such as condenser, absorber, generator, and evaporator temperatures have been investigated. The influence of the various operating parameters on the performance coefficient and exergy efficiency of this cycle has been studied. The results show that when the temperature of different parts increases, the performance coefficient and the exergy efficiency of the cycle decrease, except for evaporator and generator, that causes an increase in coefficient of performance (COP). According to the results, absorber and ejector have the highest exergy losses in the studied conditions.

Keywords: absorption refrigeration, COP, ejector, exergy efficiency

Procedia PDF Downloads 295
5440 Co-Existence of Central Serous Retinopathy and Diabetic Retinopathy: A Diagnostic Dilemma

Authors: Avantika Verma

Abstract:

Diabetic retinopathy (DR) and Central serous retinopathy (CSR) are 2 distinct entities, with difference in age of presentation, eitiopathogenesis and clinical features, but when occurring together, can be a diagnostic dilemma and requires careful evaluation. Case study of 3 patients with long standing diabetes (>15yrs) and features of Central serous retinopathy was done at Bangalore West Lions Superspeciality Eye Hospital, Bangalore, India in 2013. Even though diabetic retinopathy and CSR have different pathologies, they can coexist. The reason for coexistence could be the following: A patient with CSR as a young adult could develop DR in later years. Stress could be the contributing factor in older patient with diabetes.Stress could be a common factor for both, as it is one of the important factors in the pathogenesis of Maturity Onset Diabetes Miletus (MODY). In any situation, a careful evaluation is necessary to differentiate the cause of fundus picture, as treatment differs for the two diseases.

Keywords: central serous retinopathy, diabetic retinopathy, existence, stress

Procedia PDF Downloads 205
5439 Pyramid Binary Pattern for Age Invariant Face Verification

Authors: Saroj Bijarnia, Preety Singh

Abstract:

We propose a simple and effective biometrics system based on face verification across aging using a new variant of texture feature, Pyramid Binary Pattern. This employs Local Binary Pattern along with its hierarchical information. Dimension reduction of generated texture feature vector is done using Principal Component Analysis. Support Vector Machine is used for classification. Our proposed method achieves an accuracy of 92:24% and can be used in an automated age-invariant face verification system.

Keywords: biometrics, age invariant, verification, support vector machine

Procedia PDF Downloads 316
5438 The Tourism Pattern Based on Lifestyle: A Case Study of Suzhou City in China

Authors: Ling Chen, Lanyan Peng

Abstract:

In the new round of institutional reform of the State Council, Ministry of Culture and Ministry of Tourism were formed into a new department, Ministry of Culture and Tourism, which embodied the idea of the fusion development of cultural and tourism industries. At the same time, domestic tourists pay more attention to the tourism experience and tourism quality. The tourism patterns have been changed from the sightseeing mode of the individual scenic spot to the lifestyle mode of feeling the cultural atmosphere of the tourist destination. Therefore, this paper focuses on the tourism pattern based on lifestyle, studies the development status, content, and implementation measures of the tourism pattern. As the tourism pattern based on lifestyle integrating cultural and tourism industries in-depth, tourists can experience the living atmosphere, living conditions and living quality of the tourist destination, and deeply understand the urban cultural connotation during the trip. Suzhou has taken a series of measures to build up a tourism pattern based on lifestyle-'Suzhou life' tourism, including regional planning of tourism, integration of cultural resources, construction of urban atmosphere, and upgrading infrastructure. 'Suzhou life' tourism is based on the Suzhou food (cooked wheaten food, dim sum, specialty snacks), tourist attractions (Suzhou gardens, the ancient city) and characteristic recreational ways (appreciating Kun opera, enjoying Suzhou Pingtan, tea drinking). And the continuous integration of the three components above meet the spiritual, cultural needs of tourists and upgrade the tourism pattern based on lifestyle. Finally, the paper puts forward the tourism pattern planning suggestions.

Keywords: tourism pattern, lifestyle, integration of cultural and tourism industries, Suzhou life

Procedia PDF Downloads 212
5437 Growth Pattern Analysis of Khagrachari Pourashava

Authors: Kutub Uddin Chisty, Md. Kamrul Islam, Md. Ashraful Islam

Abstract:

Growth pattern is an important factor for a city because it can help to predict future growth trend and development of a city. Khagrachari District is one of the three hill tracts districts in Bangladesh. It is bordered by the Indian State of Tripura on the north, Rangamati and Chittagong districts on the south, Rangamati district on the east, Chittagong district and the Indian State of Tripura on the west. Khagrachari Pourashava is surrounded by hills and waterways. The Pourashava area is mostly inhibited by non-tribal population, while tribal population lives in hilly regions within and around the Pourashava area. The hilly area growth is different. Based on questioners and expert opinions survey, growth pattern of Khagrachari is evaluated. Different culture, history, tribal people, non-tribal people enrich the hilly heritages. In our study, we analyse the city growth pattern and identify the prominent factors that influence the city growth. Thus, it can help us to identify growth trend of the city.

Keywords: growth pattern, growth trend, prominent factors, regional development

Procedia PDF Downloads 314
5436 Analysis of the Operating Load of Gas Bearings in the Gas Generator of the Turbine Engine during a Deceleration to Dash Maneuver

Authors: Zbigniew Czyz, Pawel Magryta, Mateusz Paszko

Abstract:

The paper discusses the status of loads acting on the drive unit of the unmanned helicopter during deceleration to dash maneuver. Special attention was given for the loads of bearings in the gas generator turbine engine, in which will be equipped a helicopter. The analysis was based on the speed changes as a function of time for manned flight of helicopter PZL W3-Falcon. The dependence of speed change during the flight was approximated by the least squares method and then determined for its changes in acceleration. This enabled us to specify the forces acting on the bearing of the gas generator in static and dynamic conditions. Deceleration to dash maneuvers occurs in steady flight at a speed of 222 km/h by horizontal braking and acceleration. When the speed reaches 92 km/h, it dynamically changes an inclination of the helicopter to the maximum acceleration and power to almost maximum and holds it until it reaches its initial speed. This type of maneuvers are used due to ineffective shots at significant cruising speeds. It is, therefore, important to reduce speed to the optimum as soon as possible and after giving a shot to return to the initial speed (cruising). In deceleration to dash maneuvers, we have to deal with the force of gravity of the rotor assembly, gas aerodynamics forces and the forces caused by axial acceleration during this maneuver. While we can assume that the working components of the gas generator are designed so that axial gas forces they create could balance the aerodynamic effects, the remaining ones operate with a value that results from the motion profile of the aircraft. Based on the analysis, we can make a compilation of the results. For this maneuver, the force of gravity (referring to statistical calculations) respectively equals for bearing A = 5.638 N and bearing B = 1.631 N. As overload coefficient k in this direction is 1, this force results solely from the weight of the rotor assembly. For this maneuver, the acceleration in the longitudinal direction achieved value a_max = 4.36 m/s2. Overload coefficient k is, therefore, 0.44. When we multiply overload coefficient k by the weight of all gas generator components that act on the axial bearing, the force caused by axial acceleration during deceleration to dash maneuver equals only 3.15 N. The results of the calculations are compared with other maneuvers such as acceleration and deceleration and jump up and jump down maneuvers. This work has been financed by the Polish Ministry of Science and Higher Education.

Keywords: gas bearings, helicopters, helicopter maneuvers, turbine engines

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5435 Pattern the Location and Area of Earth-Dumping Stations from Vehicle GPS Data in Taiwan

Authors: Chun-Yuan Chen, Ming-Chang Li, Xiu-Hui Wen, Yi-Ching Tu

Abstract:

The objective of this study explores GPS (Global Positioning System) applied to trace construction vehicles such as trucks or cranes, help to pattern the earth-dumping stations of traffic construction in Taiwan. Traffic construction in this research is defined as the engineering of high-speed railways, expressways, and which that distance more than kilometers. Audit the location and check the compliance with regulations of earth-dumping stations is one of important tasks in Taiwan EPA. Basically, the earth-dumping station was known as one source of particulate matter from air pollution during construction process. Due to GPS data can be analyzed quickly and be used conveniently, this study tried to find out dumping stations by modeling vehicles tracks from GPS data during work cycle of construction. The GPS data updated from 13 vehicles related to an expressway construction in central Taiwan. The GPS footprints were retrieved to Keyhole Markup Language (KML) files so that can pattern the tracks of trucks by computer applications, the data was collected about eight months- from Feb. to Oct. in 2017. The results of GPS footprints identified dumping station and outlined the areas of earthwork had been passed to the Taiwan EPA for on-site inspection. Taiwan EPA had issued advice comments to the agency which was in charge of the construction to prevent the air pollution. According to the result of this study compared to the commonly methods in inspecting environment by manual collection, the GPS with KML patterning and modeling method can consumes less time. On the other hand, through monitoring the GPS data from construction vehicles could be useful for administration to development and implementation of strategies in environmental management.

Keywords: automatic management, earth-dumping station, environmental management, Global Positioning System (GPS), particulate matter, traffic construction

Procedia PDF Downloads 139
5434 Reliability Assessment for Tie Line Capacity Assistance of Power Systems Based on Multi-Agent System

Authors: Nadheer A. Shalash, Abu Zaharin Bin Ahmad

Abstract:

Technological developments in industrial innovations have currently been related to interconnected system assistance and distribution networks. This important in order to enable an electrical load to continue receive power in the event of disconnection of load from the main power grid. This paper represents a method for reliability assessment of interconnected power systems based. The multi-agent system consists of four agents. The first agent was the generator agent to using as connected the generator to the grid depending on the state of the reserve margin and the load demand. The second was a load agent is that located at the load. Meanwhile, the third is so-called "the reverse margin agent" that to limit the reserve margin between 0-25% depend on the load and the unit size generator. In the end, calculation reliability Agent can be calculate expected energy not supplied (EENS), loss of load expectation (LOLE) and the effecting of tie line capacity to determine the risk levels Roy Billinton Test System (RBTS) can use to evaluated the reliability indices by using the developed JADE package. The results estimated of the reliability interconnection power systems presented in this paper. The overall reliability of power system can be improved. Thus, the market becomes more concentrated against demand increasing and the generation units were operating in relation to reliability indices.

Keywords: reliability indices, load expectation, reserve margin, daily load, probability, multi-agent system

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5433 Dynamic Shock Bank Liquidity Analysis

Authors: C. Recommandé, J. C. Blind, A. Clavel, R. Gourichon, V. Le Gal

Abstract:

Simulations are developed in this paper with usual DSGE model equations. The model is based on simplified version of Smets-Wouters equations in use at European Central Bank which implies 10 macro-economic variables: consumption, investment, wages, inflation, capital stock, interest rates, production, capital accumulation, labour and credit rate, and allows take into consideration the banking system. Throughout the simulations, this model will be used to evaluate the impact of rate shocks recounting the actions of the European Central Bank during 2008.

Keywords: CC-LM, Central Bank, DSGE, liquidity shock, non-standard intervention

Procedia PDF Downloads 426
5432 Synchronous Generator in Case Voltage Sags for Different Loads

Authors: Benalia Nadia, Bensiali Nadia, Zezouri Noura

Abstract:

This paper studies the effects of voltage sags, both symmetrical and unsymmetrical, on the three-phase Synchronous Machine (SM) when powering an isolate load or infinite bus bar. The vast majority of the electrical power generation systems in the world is consist of synchronous generators coupled to the electrical network though a transformer. Voltage sags on SM cause speed variations, current and torque peaks and hence may cause tripping and equipment damage. The consequences of voltage sags in the machine behavior depends on different factors such as its magnitude (or depth), duration , the parameters of the machine and also the size of load. In this study, we consider the machine feeds an infinite bus bar in the first and the isolate load using symmetric and asymmetric defaults to see the behavior of the machine in both case the simulation have been used on SIMULINK MATLAB.

Keywords: power quality, voltage sag, synchronous generator, infinite system

Procedia PDF Downloads 649
5431 Unsupervised Images Generation Based on Sloan Digital Sky Survey with Deep Convolutional Generative Neural Networks

Authors: Guanghua Zhang, Fubao Wang, Weijun Duan

Abstract:

Convolution neural network (CNN) has attracted more and more attention on recent years. Especially in the field of computer vision and image classification. However, unsupervised learning with CNN has received less attention than supervised learning. In this work, we use a new powerful tool which is deep convolutional generative adversarial networks (DCGANs) to generate images from Sloan Digital Sky Survey. Training by various star and galaxy images, it shows that both the generator and the discriminator are good for unsupervised learning. In this paper, we also took several experiments to choose the best value for hyper-parameters and which could help to stabilize the training process and promise a good quality of the output.

Keywords: convolution neural network, discriminator, generator, unsupervised learning

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5430 On the convergence of the Mixed Integer Randomized Pattern Search Algorithm

Authors: Ebert Brea

Abstract:

We propose a novel direct search algorithm for identifying at least a local minimum of mixed integer nonlinear unconstrained optimization problems. The Mixed Integer Randomized Pattern Search Algorithm (MIRPSA), so-called by the author, is based on a randomized pattern search, which is modified by the MIRPSA for finding at least a local minimum of our problem. The MIRPSA has two main operations over the randomized pattern search: moving operation and shrinking operation. Each operation is carried out by the algorithm when a set of conditions is held. The convergence properties of the MIRPSA is analyzed using a Markov chain approach, which is represented by an infinite countable set of state space λ, where each state d(q) is defined by a measure of the qth randomized pattern search Hq, for all q in N. According to the algorithm, when a moving operation is carried out on the qth randomized pattern search Hq, the MIRPSA holds its state. Meanwhile, if the MIRPSA carries out a shrinking operation over the qth randomized pattern search Hq, the algorithm will visit the next state, this is, a shrinking operation at the qth state causes a changing of the qth state into (q+1)th state. It is worthwhile pointing out that the MIRPSA never goes back to any visited states because the MIRPSA only visits any qth by shrinking operations. In this article, we describe the MIRPSA for mixed integer nonlinear unconstrained optimization problems for doing a deep study of its convergence properties using Markov chain viewpoint. We herein include a low dimension case for showing more details of the MIRPSA, when the algorithm is used for identifying the minimum of a mixed integer quadratic function. Besides, numerical examples are also shown in order to measure the performance of the MIRPSA.

Keywords: direct search, mixed integer optimization, random search, convergence, Markov chain

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5429 On Lie-Central Derivations and Almost Inner Lie-Derivations of Leibniz Algebras

Authors: Natalia Pacheco Rego

Abstract:

The Liezation functor is a map from the category of Leibniz algebras to the category of Lie algebras, which assigns a Leibniz algebra to the Lie algebra given by the quotient of the Leibniz algebra by the ideal spanned by the square elements of the Leibniz algebra. This functor is left adjoint to the inclusion functor that considers a Lie algebra as a Leibniz algebra. This environment fits in the framework of central extensions and commutators in semi-abelian categories with respect to a Birkhoff subcategory, where classical or absolute notions are relative to the abelianization functor. Classical properties of Leibniz algebras (properties relative to the abelianization functor) were adapted to the relative setting (with respect to the Liezation functor); in general, absolute properties have the corresponding relative ones, but not all absolute properties immediately hold in the relative case, so new requirements are needed. Following this line of research, it was conducted an analysis of central derivations of Leibniz algebras relative to the Liezation functor, called as Lie-derivations, and a characterization of Lie-stem Leibniz algebras by their Lie-central derivations was obtained. In this paper, we present an overview of these results, and we analyze some new properties concerning Lie-central derivations and almost inner Lie-derivations. Namely, a Leibniz algebra is a vector space equipped with a bilinear bracket operation satisfying the Leibniz identity. We define the Lie-bracket by [x, y]lie = [x, y] + [y, x] , for all x, y . The Lie-center of a Leibniz algebra is the two-sided ideal of elements that annihilate all the elements in the Leibniz algebra through the Lie-bracket. A Lie-derivation is a linear map which acts as a derivative with respect to the Lie-bracket. Obviously, usual derivations are Lie-derivations, but the converse is not true in general. A Lie-derivation is called a Lie-central derivation if its image is contained in the Lie-center. A Lie-derivation is called an almost inner Lie-derivation if the image of an element x is contained in the Lie-commutator of x and the Leibniz algebra. The main results we present in this talk refer to the conditions under which Lie-central derivation and almost inner Lie-derivations coincide.

Keywords: almost inner Lie-derivation, Lie-center, Lie-central derivation, Lie-derivation

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5428 Technical and Economic Analysis Effects of Various Parameters on the Performance of Heat Recovery System on Gas Complex Turbo Generators

Authors: Hefzollah Mohammadian, Mohammad Bagher Heidari

Abstract:

This paper deals with the technical and economic effects of various parameters on the performance of heat recovery system on gas complex turbo generator. Given the importance of this issue, that is the main goal of economic efficiency and reduces costs; this project has been implemented similar plans in which the target is the implementation of specific patterns. The project will also help us in the process of gas refineries and the actual efficiency of the process after adding a system to analyze the turbine and predict potential problems and fix them and take appropriate measures according to the results of simulation analysis and results of the process gain. The results of modeling and the effect of different parameters on this line, have been done using Thermo Flow.

Keywords: turbo compressor, turbo generator, heat recovery boiler, gas turbines

Procedia PDF Downloads 275
5427 Stability Analysis of a Low Power Wind Turbine for the Simultaneous Generation of Energy through Two Electric Generators

Authors: Daniel Icaza, Federico Córdova, Chiristian Castro, Fernando Icaza, Juan Portoviejo

Abstract:

In this article, the mathematical model is presented, and simulations were carried out using specialized software such as MATLAB before the construction of a 900-W wind turbine. The present study was conducted with the intention of taking advantage of the rotation of the blades of the wind generator after going through a process of amplification of speed by means of a system of gears to finally mechanically couple two electric generators of similar characteristics. This coupling allows generating a maximum voltage of 6 V in DC for each generator and putting in series the 12 V DC is achieved, which is later stored in batteries and used when the user requires it. Laboratory tests were made to verify the level of power generation produced based on the wind speed at the entrance of the blades.

Keywords: smart grids, wind turbine, modeling, renewable energy, robust control

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5426 Scouring Rate Pattern/Monitoring at Coastal and Offshore Structures

Authors: Ahmad Saifullah Mazlan, Hossein Basser, Shatirah Akib

Abstract:

Scouring pattern evaluation and measuring its depth around coastal and offshore structures is very essential issue to assure the safety of the structures as well as providing needed design parameters. Scouring is known as one of the important phenomena which threatens the safety of infrastructures. Several countermeasures have been developed to control scouring by protecting the structures against water flow attack directly or indirectly by changing the water flow pattern. Recently, monitoring methods for estimating water flow pattern and scour depth are studied to track the safety of structures. Since most of studies regarding scouring is related to monitoring scouring around piers in rivers therefore it is necessary to develop researches investigating scouring around piers in coastal and offshore areas. This paper describes a review of monitoring methods may be used for detecting scour depth around piers in coastal and offshore structures.

Keywords: scour, monitoring, pier, coastal, offshore

Procedia PDF Downloads 609
5425 Inverterless Grid Compatible Micro Turbine Generator

Authors: S. Ozeri, D. Shmilovitz

Abstract:

Micro‐Turbine Generators (MTG) are small size power plants that consist of a high speed, gas turbine driving an electrical generator. MTGs may be fueled by either natural gas or kerosene and may also use sustainable and recycled green fuels such as biomass, landfill or digester gas. The typical ratings of MTGs start from 20 kW up to 200 kW. The primary use of MTGs is for backup for sensitive load sites such as hospitals, and they are also considered a feasible power source for Distributed Generation (DG) providing on-site generation in proximity to remote loads. The MTGs have the compressor, the turbine, and the electrical generator mounted on a single shaft. For this reason, the electrical energy is generated at high frequency and is incompatible with the power grid. Therefore, MTGs must contain, in addition, a power conditioning unit to generate an AC voltage at the grid frequency. Presently, this power conditioning unit consists of a rectifier followed by a DC/AC inverter, both rated at the full MTG’s power. The losses of the power conditioning unit account to some 3-5%. Moreover, the full-power processing stage is a bulky and costly piece of equipment that also lowers the overall system reliability. In this study, we propose a new type of power conditioning stage in which only a small fraction of the power is processed. A low power converter is used only to program the rotor current (i.e. the excitation current which is substantially lower). Thus, the MTG's output voltage is shaped to the desired amplitude and frequency by proper programming of the excitation current. The control is realized by causing the rotor current to track the electrical frequency (which is related to the shaft frequency) with a difference that is exactly equal to the line frequency. Since the phasor of the rotation speed and the phasor of the rotor magnetic field are multiplied, the spectrum of the MTG generator voltage contains the sum and the difference components. The desired difference component is at the line frequency (50/60 Hz), whereas the unwanted sum component is at about twice the electrical frequency of the stator. The unwanted high frequency component can be filtered out by a low-pass filter leaving only the low-frequency output. This approach allows elimination of the large power conditioning unit incorporated in conventional MTGs. Instead, a much smaller and cheaper fractional power stage can be used. The proposed technology is also applicable to other high rotation generator sets such as aircraft power units.

Keywords: gas turbine, inverter, power multiplier, distributed generation

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5424 A Comparison of Dietary Quality and Nutritional Adequacy of Meal Plans of a Diet Prescription Generator Web App against the Australian Guidelines to Healthy Eating

Authors: Ananda Perera

Abstract:

Diet therapy has a positive impact on many diseases in General Practice. If a meal plan can be generated as easily as writing a drug prescription for dyspepsia, then the evidence and practice gap in nutrition therapy can be narrowed. Meal plans of 50 diet prescriptions were compared with the criteria for a healthy diet given by Australian authorities. The energy value of each meal plan was compared with the recommended daily energy requirements of the authorities for Diet Prescription Generator (DPG) accuracy. Meal plans generated were within the criteria laid down by the Australian authorities for a healthy diet.

Keywords: dieting, obesity, diabetes, weight loss, computerized decision support systems, dieting software, CDSS, meal plans

Procedia PDF Downloads 110
5423 Unveiling the Realities of Marrying Too Young: Evidence from Child Brides in Sub-Saharan Africa and Infant Mortality Implications

Authors: Emmanuel Olamijuwon

Abstract:

Despite laws against child marriage - a violation against child rights, the practice remains widespread in sub-Saharan Africa and globally partly because of persistent poverty, gender inequality, protection and the need to reinforce family ties. Using pooled data from the recent demographic and health surveys of 20-sub-Saharan African countries with a regional representative sample of 36,943 girls under 18 years, this study explores the prevalence, pattern and infant mortality implications of this marriage type while also examining its regional variations. Indications from the study are that child marriage is still very high in the region with variations above one-tenth in West, Central and Southern Africa regions except in the East African region where only about 7% of children under 18 were already married. Preliminary findings also suggest that about one-in-ten infant deaths were to child brides many of whom were residing in poor households, rural residence, unemployed and have less than secondary education. Based on these findings, it is, therefore, important that government of African countries addresses critical issues through increased policies towards increasing enrollment of girl children in schools as many of these girls are not likely to have any economic benefit to the region if the observed pattern continues.

Keywords: child marriage, infant mortality, Africa, child brides

Procedia PDF Downloads 214
5422 Growth Pattern and Condition Factor of Oreochromis niloticus and Sarotherodon galilaeus in Epe Lagoon, Lagos State, Nigeria

Authors: Ahmed Bolaji Alarape, Oluwatobi Damilola Aba

Abstract:

The growth pattern of Oreochromis niloticus and Sarotherodon galilaeus in Epe Lagoon Lagos State was investigated. One hundred (100) samples of each species were collected from fishermen at the landing site. They were transported to the Fisheries Laboratory of National Institute of Oceanography for identification, sexing morphometric measurement. The results showed that 58.0% and 56.0 % of the O.niloticus and S.galilaeus were female respectively while 42.0% and 44.0% were male respectively. The length-weight relationship of O.niloticus showed a strong regression coefficient (r = 0.944) (p<0.05) for the combined sex, (r =0.901) (p<0.05) for female and (r=0.985) (p<.05) for male with b-value of 2.5, 3.1 and 2.8 respectively. The S.galilaeus also showed a regression coefficient of r=0.970; p<0.05 for the combined sex, r=0.953; p<0.05 for the female and r= 0.979; p<0.05 for the male with b-value of 3.4, 3.1 and 3.6 respectively. O.niloticus showed an isometric growth pattern both in male and female. The condition factor in O.niloticus are 1.93 and 1.95 for male and female respectively while that of S.galilaeus is 1.95 for both sexes. Positive allometric was observed in both species except the male O.niloticus that showed negative allometric growth pattern. From the results of this study, the growth pattern of the two species indicated a good healthy environment.

Keywords: Epe Lagoon, length-weight relationship, Oreochromis niloticus, Sarotherodon galilaeus

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5421 Retina Registration for Biometrics Based on Characterization of Retinal Feature Points

Authors: Nougrara Zineb

Abstract:

The unique structure of the blood vessels in the retina has been used for biometric identification. The retina blood vessel pattern is a unique pattern in each individual and it is almost impossible to forge that pattern in a false individual. The retina biometrics’ advantages include high distinctiveness, universality, and stability overtime of the blood vessel pattern. Once the creases have been extracted from the images, a registration stage is necessary, since the position of the retinal vessel structure could change between acquisitions due to the movements of the eye. Image registration consists of following steps: Feature detection, feature matching, transform model estimation and image resembling and transformation. In this paper, we present an algorithm of registration; it is based on the characterization of retinal feature points. For experiments, retinal images from the DRIVE database have been tested. The proposed methodology achieves good results for registration in general.

Keywords: fovea, optic disc, registration, retinal images

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5420 Power Quality Audit Using Fluke Analyzer

Authors: N. Ravikumar, S. Krishnan, B. Yokeshkumar

Abstract:

In present days, the power quality issues are increases due to non-linear loads like fridge, AC, washing machines, induction motor, etc. This power quality issues will affects the output voltages, output current, and output power of the total performance of the generator. This paper explains how to test the generator using the Fluke 435 II series power quality analyser. This Fluke 435 II series power quality analyser is used to measure the voltage, current, power, energy, total harmonic distortion (THD), current harmonics, voltage harmonics, power factor, and frequency. The Fluke 435 II series power quality analyser have several advantages. They are i) it will records output in analog and digital format. ii) the fluke analyzer will records at every 0.25 sec. iii) it will also measure all the electrical parameter at a time.

Keywords: THD, harmonics, power quality, TNEB, Fluke 435

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5419 A Simple Fluid Dynamic Model for Slippery Pulse Pattern in Traditional Chinese Pulse Diagnosis

Authors: Yifang Gong

Abstract:

Pulse diagnosis is one of the most important diagnosis methods in traditional Chinese medicine. It is also the trickiest method to learn. It is known as that it can only to be sensed not explained. This becomes a serious threat to the survival of this diagnostic method. However, there are a large amount of experiences accumulated during the several thousand years of practice of Chinese doctors. A pulse pattern called 'Slippery pulse' is one of the indications of pregnancy. A simple fluid dynamic model is proposed to simulate the effects of the existence of a placenta. The placenta is modeled as an extra plenum in an extremely simplified fluid network model. It is found that because of the existence of the extra plenum, indeed the pulse pattern shows a secondary peak in one pulse period. As for the author’s knowledge, this work is the first time to show the link between Pulse diagnoses and basic physical principle. Key parameters which might affect the pattern are also investigated.

Keywords: Chinese medicine, flow network, pregnancy, pulse

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5418 Health Effect of the Central European Diet in Postmenopausal Women with Increased Waist Circumference: A Preliminary Study

Authors: Joanna Bajerska, Agata Chmurzyńska, Agata Muzsik, Patrycja Krzyżanowska, Klaudia Łochocka, Jarosław Walkowiak

Abstract:

The Mediterranean diet (MED) is regarded as beneficial in the therapy of central obesity-associated metabolic abnormalities. However, in the traditional diet of the Central European countries, food items with positive nutritional profiles (rye bread, oats, buckwheat, herrings, linseed and rapeseed oil, berries, apples, plums, root vegetables etc.) are also used. We hypothesized that the Central European Diet (CED) may be comparatively effective in reducing symptoms of central obesity as MED. We tested the health effects of the CED, which is an environmentally friendly regional diet and the traditional MED diet in a group of postmenopausal centrally obese women. A total 58 with a mean age of 60 y (50-70y), body mass index (in kg/m(2)) of 33.4 (22.6-47.3), and waist circumference of 105 cm (87.5-137 cm) were randomly assigned to receive either the diet based on food items commonly used in Central Europe (the CED group; n = 29) or the Mediterranean diet (the MED group; n = 29) for 15 weeks. Body mass and body composition were measured with a Bod Pod (Cosmed, Italy). A non-elastic flexible measuring tape was used to measure waist circumference. Additionally, blood pressure, plasma lipid and glucose levels were assessed with the use of a biochemical analyzer. A total of 50 subjects [86% (CED 83%; MED 90%)] completed the intervention. A high dietary compliance for both described diets was achieved. The mean (±SEM) weight and waist circumference changes were -7.4 ± 0.7 kg; -8.3 ± 0.7 cm and -8.1 ± 0.5 kg; -7.1 ± 0.6 cm for the CED and MED groups, respectively. Moreover, there were no differences between the effectiveness of the diets used in terms of the influence on fat mass, blood pressure, and biochemical parameters. The preliminary data suggest that both described diets may be successfully used for improving central obesity-associated metabolic abnormalities. The project was financed by the National Science Centre awarded based on the number of decision DEC-013/09/B/NZ9/02365

Keywords: central european diet, central obesity, Mediterranean diet, metabolic abnormalities

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5417 Sustainable Ionized Gas Thermoelectric Generator: Comparative Theoretical Evaluation and Efficiency Estimation

Authors: Mohammad Bqoor, Mohammad Hamdan, Isam Janajreh, Sufian Abedrabbo

Abstract:

This extensive theoretical study on a novel Ionized Gas Thermoelectric Generator (IG-TEG) system has shown the ability of continuous energy extracting from the thermal energy of ambient air around standard room temperature and even below. This system does not need a temperature gradient in order to work, unlike the other TEGs that use the Seebeck effect, and therefore this new system can be utilized in sustainable energy systems, as well as in green cooling solutions, by extracting energy instead of wasting energy in compressing the gas for cooling. This novel system was designed based on Static Ratchet Potential (SRP), which is known as a spatially asymmetric electric potential produced by an array of positive and negative electrodes. The ratchet potential produces an electrical current from the random Brownian Motion of charged particles that are driven by thermal energy. The key parameter of the system is particle transportation, and it was studied under the condition of flashing ratchet potentials utilizing several methods and examined experimentally, ensuring its functionality. In this study, a different approach is pursued to estimate particle transportation by evaluating the charged particle distribution and applying the other conditions of the SRP, and showing continued energy harvesting potency from the particles’ transportation. Ultimately, power levels of 10 Watt proved to be achievable from a 1 m long system tube of 10 cm radius.

Keywords: thermoelectric generator, ratchet potential, Brownian ratchet, energy harvesting, sustainable energy, green technology

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