Search results for: four-level output voltage
2386 Braille Code Matrix
Authors: Mohammed E. A. Brixi Nigassa, Nassima Labdelli, Ahmed Slami, Arnaud Pothier, Sofiane Soulimane
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According to the world health organization (WHO), there are almost 285 million people with visual disability, 39 million of these people are blind. Nevertheless, there is a code for these people that make their life easier and allow them to access information more easily; this code is the Braille code. There are several commercial devices allowing braille reading, unfortunately, most of these devices are not ergonomic and too expensive. Moreover, we know that 90 % of blind people in the world live in low-incomes countries. Our contribution aim is to concept an original microactuator for Braille reading, as well as being ergonomic, inexpensive and lowest possible energy consumption. Nowadays, the piezoelectric device gives the better actuation for low actuation voltage. In this study, we focus on piezoelectric (PZT) material which can bring together all these conditions. Here, we propose to use one matrix composed by six actuators to form the 63 basic combinations of the Braille code that contain letters, numbers, and special characters in compliance with the standards of the braille code. In this work, we use a finite element model with Comsol Multiphysics software for designing and modeling this type of miniature actuator in order to integrate it into a test device. To define the geometry and the design of our actuator, we used physiological limits of perception of human being. Our results demonstrate in our study that piezoelectric actuator could bring a large deflection out-of-plain. Also, we show that microactuators can exhibit non uniform compression. This deformation depends on thin film thickness and the design of membrane arm. The actuator composed of four arms gives the higher deflexion and it always gives a domed deformation at the center of the deviceas in case of the Braille system. The maximal deflection can be estimated around ten micron per Volt (~ 10µm/V). We noticed that the deflection according to the voltage is a linear function, and this deflection not depends only on the voltage the voltage, but also depends on the thickness of the film used and the design of the anchoring arm. Then, we were able to simulate the behavior of the entire matrix and thus display different characters in Braille code. We used these simulations results to achieve our demonstrator. This demonstrator is composed of a layer of PDMS on which we put our piezoelectric material, and then added another layer of PDMS to isolate our actuator. In this contribution, we compare our results to optimize the final demonstrator.Keywords: Braille code, comsol software, microactuators, piezoelectric
Procedia PDF Downloads 3492385 Discrete Sliding Modes Regulator with Exponential Holder for Non-Linear Systems
Authors: G. Obregon-Pulido , G. C. Solis-Perales, J. A. Meda-Campaña
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In this paper, we present a sliding mode controller in discrete time. The design of the controller is based on the theory of regulation for nonlinear systems. In the problem of disturbance rejection and/or output tracking, it is known that in discrete time, a controller that uses the zero-order holder only guarantees tracking at the sampling instances but not between instances. It is shown that using the so-called exponential holder, it is possible to guarantee asymptotic zero output tracking error, also between the sampling instant. For stabilizing the problem of close loop system we introduce the sliding mode approach relaxing the requirements of the existence of a linear stabilizing control law.Keywords: regulation theory, sliding modes, discrete controller, ripple-free tracking
Procedia PDF Downloads 472384 Electrical Tortuosity across Electrokinetically Remediated Soils
Authors: Waddah S. Abdullah, Khaled F. Al-Omari
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Electrokinetic remediation is one of the most influential and effective methods to decontaminate contaminated soils. Electroosmosis and electromigration are the processes of electrochemical extraction of contaminants from soils. The driving force that causes removing contaminants from soils (electroosmosis process or electromigration process) is voltage gradient. Therefore, the electric field distribution throughout the soil domain is extremely important to investigate and to determine the factors that help to establish a uniform electric field distribution in order to make the clean-up process work properly and efficiently. In this study, small-sized passive electrodes (made of graphite) were placed at predetermined locations within the soil specimen, and the voltage drop between these passive electrodes was measured in order to observe the electrical distribution throughout the tested soil specimens. The electrokinetic test was conducted on two types of soils; a sandy soil and a clayey soil. The electrical distribution throughout the soil domain was conducted with different tests properties; and the electrical field distribution was observed in three-dimensional pattern in order to establish the electrical distribution within the soil domain. The effects of density, applied voltages, and degree of saturation on the electrical distribution within the remediated soil were investigated. The distribution of the moisture content, concentration of the sodium ions, and the concentration of the calcium ions were determined and established in three-dimensional scheme. The study has shown that the electrical conductivity within soil domain depends on the moisture content and concentration of electrolytes present in the pore fluid. The distribution of the electrical field in the saturated soil was found not be affected by its density. The study has also shown that high voltage gradient leads to non-uniform electric field distribution within the electroremediated soil. Very importantly, it was found that even when the electric field distribution is uniform globally (i.e. between the passive electrodes), local non-uniformity could be established within the remediated soil mass. Cracks or air gaps formed due to temperature rise (because of electric flow in low conductivity regions) promotes electrical tortuosity. Thus, fracturing or cracking formed in the remediated soil mass causes disconnection of electric current and hence, no removal of contaminant occur within these areas.Keywords: contaminant removal, electrical tortuousity, electromigration, electroosmosis, voltage distribution
Procedia PDF Downloads 4132383 Electro-Optic Parameters of Ferroelectric Particles- Liquid Crystal Composites
Authors: T. D. Ibragimov, A. R. Imamaliyev, G. M. Bayramov
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Influence of barium titanate particles on electro-optic properties of liquid crystal 4-cyano-4′-pentylbiphenyl (5CB) with positive dielectric anisotropy and the liquid crystalline (LC) mixture Н-37 consisting of 4-methoxybezylidene-4'–butylaniline and 4-ethoxybezylidene-4'–butylaniline with negative dielectric anisotropy was investigated. It was shown that a presence of particles inside 5СВ and H-37 decreased the clearing temperature from 35.2 °С to 32.5°С and from 61.2 oC to 60.1oC, correspondingly. The threshold voltage of the Fredericksz effect became 0.3 V for the BaTiO3-5CB colloid while the beginning of this effect of the pure 5СВ was observed at 2.1 V. Threshold voltage of the Fredericksz effect increased from 2.8 V to up 3.1 V at additive of particles into H-37. A rise time of the BaTiO3-5CB colloid improved while a decay time worsened in comparison with the pure 5CB at all applied voltages. The inverse trends were observed for the H-37 matrix, namely, a rise time worsened and a decay time improved. Among other things, the effect of fast light modulation was studied at application of the rectangular impulse with direct bias to an electro-optical cell with the BaTiO3 particles+5CB and the pure 5CB. At this case, a rise time of the composite worsened, a decay time improved in comparison with the pure 5CB. The pecularities of electrohydrodynamic instability (EHDI) formation was also investigated into the composite with the H-37 matrix. It was found that the voltage of the EHDI formation decreased, a rise time increased and a decay time decreased in comparison with the pure H-37. First of all, experimental results are explained by appearance of local electric fields near the polarized ferroelectric particles at application of external electric field and an existence of the additional obstacles (particles) for movement of ions.Keywords: liquid crystal, ferroelectric particles, composite, electro-optics
Procedia PDF Downloads 6952382 Effect of Electric Stimulation on Characteristic Changes in Hot-Boned Beef Brisket of Different Potential Tenderness
Authors: Orose Rugchati, Kanita Thanacharoenchanaphas, Sarawut Wattanawongpitak
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In this study, the effect of electric stimulation on the quality of hot-boned beef brisket muscles was evaluated, including the tenderness, pH, temperature change, and colorant. Muscles were obtained from steers in the local slaughter house. (3 steers for each muscle), removed from the carcasses 4-hour postmortem and variable time to treated with direct current electric 1 and 5 minutes, respectively. Six different electric intensities (direct current voltage of 50, 70 and 90 Volt, pulse with 10, 20 and 40 ms) plus a control were applied to each muscle to determine the optimum treatment conditions. Hot-boned beef brisket was found to get tender with increasing treatment direct current voltage and reduction in the shear force with pulsed with electric treatment. But in a long time to treated with electric current get fading in red color and temperature increase whereas pH quite different compared to non-treated control samples.Keywords: electric stimulation, characteristic changes, hot-boned beef brisket, potential tenderness
Procedia PDF Downloads 3352381 Gender Differences in Research Output, Funding and Collaboration
Authors: Ashkan Ebadi, Andrea Schiffauerova
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In spite of the global efforts toward gender equality, female researchers are still underrepresented in professional scientific activities. The gender gap is more seen in engineering and math-intensive technological scientific fields thus calling for a specific attention. This paper focuses on the Canadian funded researchers who are active in natural sciences and engineering, and analyses the gender aspects of researchers’ performance, their scientific collaboration patterns as well as their share of the federal funding within the period of 2000 to 2010. Our results confirm the existence of gender disparity among the examined Canadian researchers. Although it was observed that male researchers have been performing better in terms of number of publications, the impact of the research was almost the same for both genders. In addition, it was observed that research funding is more biased towards male researchers and they have more control over their scientific community as well.Keywords: bibliometrics, collaboration, funding, gender differences, research output
Procedia PDF Downloads 2662380 Dynamic Modeling of Wind Farms in the Jeju Power System
Authors: Dae-Hee Son, Sang-Hee Kang, Soon-Ryul Nam
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In this paper, we develop a dynamic modeling of wind farms in the Jeju power system. The dynamic model of wind farms is developed to study their dynamic effects on the Jeju power system. PSS/E is used to develop the dynamic model of a wind farm composed of 1.5-MW doubly fed induction generators. The output of a wind farm is regulated based on pitch angle control, in which the two controllable parameters are speed and power references. The simulation results confirm that the pitch angle is successfully controlled, regardless of the variation in wind speed and output regulation.Keywords: dynamic model, Jeju power system, online limitation, pitch angle control, wind farm
Procedia PDF Downloads 3192379 Experimental and Computational Analysis of Glass Fiber Reinforced Plastic Beams with Piezoelectric Fibers
Authors: Selin Kunc, Srinivas Koushik Gundimeda, John A. Gallagher, Roselita Fragoudakis
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This study investigates the behavior of Glass Fiber Reinforced Plastic (GFRP) laminated beams additionally reinforced with piezoelectric fibers. The electromechanical behavior of piezoelectric materials coupled with high strength/low weight GFRP laminated beams can have significant application in a wide range of industries. Energy scavenging through mechanical vibrations is the focus of this study, and possible applications can be seen in the automotive industry. This study examines the behavior of such composite laminates using Classical Lamination Theory (CLT) under three-point bending conditions. Fiber orientation is optimized for the desired stiffness and deflection that yield maximum energy output. Finite element models using ABAQUS/CAE are verified through experimental testing. The optimum stacking sequences examined are [0o]s, [ 0/45o]s, and [45/-45o]s. Results show the superiority of the stacking sequence [0/45o]s, providing higher strength at a lower weight, and maximum energy output. Furthermore, laminated GFRP beams additionally reinforced with piezoelectric fibers can be used under bending to not only replace metallic component while providing similar strength at a lower weight but also provide an energy output.Keywords: classical lamination theory (CLT), energy scavenging, glass fiber reinforced plastics (GFRP), piezoelectric fibers
Procedia PDF Downloads 2972378 Application of Single Tuned Passive Filters in Distribution Networks at the Point of Common Coupling
Authors: M. Almutairi, S. Hadjiloucas
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The harmonic distortion of voltage is important in relation to power quality due to the interaction between the large diffusion of non-linear and time-varying single-phase and three-phase loads with power supply systems. However, harmonic distortion levels can be reduced by improving the design of polluting loads or by applying arrangements and adding filters. The application of passive filters is an effective solution that can be used to achieve harmonic mitigation mainly because filters offer high efficiency, simplicity, and are economical. Additionally, possible different frequency response characteristics can work to achieve certain required harmonic filtering targets. With these ideas in mind, the objective of this paper is to determine what size single tuned passive filters work in distribution networks best, in order to economically limit violations caused at a given point of common coupling (PCC). This article suggests that a single tuned passive filter could be employed in typical industrial power systems. Furthermore, constrained optimization can be used to find the optimal sizing of the passive filter in order to reduce both harmonic voltage and harmonic currents in the power system to an acceptable level, and, thus, improve the load power factor. The optimization technique works to minimize voltage total harmonic distortions (VTHD) and current total harmonic distortions (ITHD), where maintaining a given power factor at a specified range is desired. According to the IEEE Standard 519, both indices are viewed as constraints for the optimal passive filter design problem. The performance of this technique will be discussed using numerical examples taken from previous publications.Keywords: harmonics, passive filter, power factor, power quality
Procedia PDF Downloads 2992377 A Combined Approach Based on Artificial Intelligence and Computer Vision for Qualitative Grading of Rice Grains
Authors: Hemad Zareiforoush, Saeed Minaei, Ahmad Banakar, Mohammad Reza Alizadeh
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The quality inspection of rice (Oryza sativa L.) during its various processing stages is very important. In this research, an artificial intelligence-based model coupled with computer vision techniques was developed as a decision support system for qualitative grading of rice grains. For conducting the experiments, first, 25 samples of rice grains with different levels of percentage of broken kernels (PBK) and degree of milling (DOM) were prepared and their qualitative grade was assessed by experienced experts. Then, the quality parameters of the same samples examined by experts were determined using a machine vision system. A grading model was developed based on fuzzy logic theory in MATLAB software for making a relationship between the qualitative characteristics of the product and its quality. Totally, 25 rules were used for qualitative grading based on AND operator and Mamdani inference system. The fuzzy inference system was consisted of two input linguistic variables namely, DOM and PBK, which were obtained by the machine vision system, and one output variable (quality of the product). The model output was finally defuzzified using Center of Maximum (COM) method. In order to evaluate the developed model, the output of the fuzzy system was compared with experts’ assessments. It was revealed that the developed model can estimate the qualitative grade of the product with an accuracy of 95.74%.Keywords: machine vision, fuzzy logic, rice, quality
Procedia PDF Downloads 4072376 Analyzing the Empirical Link between Islamic Finance and Growth of Real Output: A Time Series Application to Pakistan
Authors: Nazima Ellahi, Danish Ramzan
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There is a growing trend among development economists regarding the importance of financial sector for economic development and growth activities. The development thus introduced, helps to promote welfare effects and poverty alleviation. This study is an attempt to find the nature of link between Islamic banking financing and development of output growth for Pakistan. Time series data set has been utilized for a time period ranging from 1990 to 2010. Following the Phillip Perron (PP) and Augmented Dicky Fuller (ADF) test of unit root this study applied Ordinary Least Squares (OLS) method of estimation and found encouraging results in favor of promoting the Islamic banking practices in Pakistan.Keywords: Islamic finance, poverty alleviation, economic growth, finance, commerce
Procedia PDF Downloads 3362375 Number of Parametrization of Discrete-Time Systems without Unit-Delay Element: Single-Input Single-Output Case
Authors: Kazuyoshi Mori
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In this paper, we consider the parametrization of the discrete-time systems without the unit-delay element within the framework of the factorization approach. In the parametrization, we investigate the number of required parameters. We consider single-input single-output systems in this paper. By the investigation, we find, on the discrete-time systems without the unit-delay element, three cases that are (1) there exist plants which require only one parameter and (2) two parameters, and (3) the number of parameters is at most three.Keywords: factorization approach, discrete-time system, parameterization of stabilizing controllers, system without unit-delay
Procedia PDF Downloads 2322374 Energy Efficient Alternate Hydraulic System Called TejHydroLift
Authors: Tejinder Singh
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This paper describes a new more efficient Hydraulic System which uses lesser work to produce more output. Conventional Hydraulic System like Hydraulic Lifts and Rams use lots of water to be pumped to produce output. TejHydroLift will do the equal amount of force with lesser input of water. The paper will show that force applied can be increased manifold without requiring to move smaller force by more distance which used to be required in Conventional Hydraulic Lifts. The paper describes one of the configurations of TejHydroLift System called “Slim Antenna TejHydroLift Configuration”. The TejHydroLift uses lesser water and hence demands lesser work to be performed to move the same load.Keywords: alternate, hydraulic system, efficient, TejHydroLift
Procedia PDF Downloads 2522373 Loss Minimization by Distributed Generation Allocation in Radial Distribution System Using Crow Search Algorithm
Authors: M. Nageswara Rao, V. S. N. K. Chaitanya, K. Amarendranath
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This paper presents an optimal allocation and sizing of Distributed Generation (DG) in Radial Distribution Network (RDN) for total power loss minimization and enhances the voltage profile of the system. The two main important part of this study first is to find optimal allocation and second is optimum size of DG. The locations of DGs are identified by Analytical expressions and crow search algorithm has been employed to determine the optimum size of DG. In this study, the DG has been placed on single and multiple allocations.CSA is a meta-heuristic algorithm inspired by the intelligent behavior of the crows. Crows stores their excess food in different locations and memorizes those locations to retrieve it when it is needed. They follow each other to do thievery to obtain better food source. This analysis is tested on IEEE 33 bus and IEEE 69 bus under MATLAB environment and the results are compared with existing methods.Keywords: analytical expression, distributed generation, crow search algorithm, power loss, voltage profile
Procedia PDF Downloads 2232372 Optimization of Submerged Arc Welding Parameters for Joining SS304 and MS1018
Authors: Jasvinder Singh, Manjinder Singh
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Welding of dissimilar materials is a complicated process due to the difference in melting point of two materials. Thermal conductivity and coefficient of thermal expansion of dissimilar materials also different; therefore, residual stresses produced in the weldment and base metal are the most critical problem associated with the joining of dissimilar materials. Tensile strength and impact toughness also reduced due to the residual stresses. In the present research work, an attempt has been made to weld SS304 and MS1018 dissimilar materials by submerged arc welding (SAW). By conducting trail, runs most effective parameters welding current, Arc voltage, welding speed and nozzle to plate distance were selected to weld these materials. The fractional factorial technique was used to optimize the welding parameters. Effect on tensile strength (TS), fracture toughness (FT) and microhardness of weldment were studied. It was concluded that by optimizing welding current, voltage and welding speed the properties of weldment can be enhanced.Keywords: SAW, Tensile Strength (TS), fracture toughness, micro hardness
Procedia PDF Downloads 5312371 Receptor-Independent Effects of Endocannabinoid Anandamide on Contractility and Electrophysiological Properties of Rat Ventricular Myocytes
Authors: Lina T. Al Kury, Oleg I. Voitychuk, Ramiz M. Ali, Sehamuddin Galadari, Keun-Hang Susan Yang, Frank Christopher Howarth, Yaroslav M. Shuba, Murat Oz
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A role for anandamide (N-arachidonoyl ethanolamide; AEA), a major endocannabinoid, in the cardiovascular system in various pathological conditions has been reported in earlier studies. In the present work, we have hypothesized that the antiarrhythmic effects reported for AEA are due to its negative inotropic effect and altered action potential (AP) characteristics. Therefore, we tested the effects of AEA on contractility and electrophysiological properties of rat ventricular myocytes. Video edge detection was used to measure myocyte shortening. Intracellular Ca2+ was measured in cells loaded with the fluorescent indicator fura-2 AM. Whole-cell patch-clamp technique was employed to investigate the effect of AEA on the characteristics of APs. AEA (1 μM) caused a significant decrease in the amplitudes of electrically-evoked myocyte shortening and Ca2+ transients and significantly decreased the duration of AP. The effect of AEA on myocyte shortening and AP characteristics was not altered in the presence of pertussis toxin (PTX, 2 µg/ml for 4 h), AM251 and SR141716 (cannabinoid type 1 receptor antagonists) or AM630 and SR 144528 (cannabinoid type 2 receptor antagonists). Furthermore, AEA inhibited voltage-activated inward Na+ (INa) and Ca2+ (IL,Ca) currents; major ionic currents shaping the APs in ventricular myocytes, in a voltage and PTX-independent manner. Collectively, the results suggest that AEA depresses ventricular myocyte contractility, by decreasing the action potential duration (APD), and inhibits the function of voltage-dependent Na+ and L-type Ca2+ channels in a manner independent of cannabinoid receptors. This mechanism may be importantly involved in the antiarrhythmic effects of anandamide.Keywords: action potential, anandamide, cannabinoid receptor, endocannabinoid, ventricular myocytes
Procedia PDF Downloads 3482370 Characterization of a LiFeOP₄ Battery Cell with Mechanical Responses
Authors: Ki-Yong Oh, Eunji Kwak, Due Su Son, Siheon Jung
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A pouch type of 10 Ah LiFePO₄ battery cell is characterized with two mechanical responses: swelling and bulk force. Both responses vary upon the state of charge significantly, whereas voltage shows flat responses, suggesting that mechanical responses can become a sensitive gauge to characterize microstructure transformation of a battery cell. The derivative of swelling s with respect to capacity Q, (ds/dQ) and the derivative of force F with respect to capacity Q, (dF/dQ) more clearly identify phase transitions of cathode and anode electrodes in the overall charge process than the derivative of voltage V with respect to capacity Q, (dV/dQ). Especially, the force versus swelling curves over the state of charge clearly elucidates three different stiffness over the state of charge oriented from phase transitions: the α-phase, the β-phase, and the metastable solid-solution phase. The observation from mechanical responses suggests that macro-scale mechanical responses of a battery cell are directly correlated to microscopic transformation of a battery cell.Keywords: force response, LiFePO₄ battery, strain response, stress response, swelling response
Procedia PDF Downloads 1612369 Analyzing Electricity Demand Multipliers in the Malaysian Economy
Authors: Hussain Ali Bekhet, Tuan Ab Rashid Bin Tuan Abdullah, Tahira Yasmin
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It is very important for electric utility to determine dominant sectors which have more impacts on electricity consumption in national economy system. The aim of this paper is to examine the electricity demand multipliers in Malaysia for (2005-2014) period. Malaysian Input-output tables, 2005 and 2010 are used. Besides, a new concept, electricity demand multiplier (EDM), is presented to identify key sectors imposing great impacts on electricity demand quantitatively. In order to testify the effectiveness of the Malaysian energy policies, it notes that there is fluctuation of the ranking sectors between 2005 and 2010. This could be reflected that there is efficiency with pace of development in Malaysia. This can be good indication for decision makers for designing future energy policies.Keywords: input-output model, demand multipliers, electricity, key sectors, Malaysia
Procedia PDF Downloads 3632368 Machine Translation Analysis of Chinese Dish Names
Authors: Xinyu Zhang, Olga Torres-Hostench
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This article presents a comparative study evaluating and comparing the quality of machine translation (MT) output of Chinese gastronomy nomenclature. Chinese gastronomic culture is experiencing an increased international acknowledgment nowadays. The nomenclature of Chinese gastronomy not only reflects a specific aspect of culture, but it is related to other areas of society such as philosophy, traditional medicine, etc. Chinese dish names are composed of several types of cultural references, such as ingredients, colors, flavors, culinary techniques, cooking utensils, toponyms, anthroponyms, metaphors, historical tales, among others. These cultural references act as one of the biggest difficulties in translation, in which the use of translation techniques is usually required. Regarding the lack of Chinese food-related translation studies, especially in Chinese-Spanish translation, and the current massive use of MT, the quality of the MT output of Chinese dish names is questioned. Fifty Chinese dish names with different types of cultural components were selected in order to complete this study. First, all of these dish names were translated by three different MT tools (Google Translate, Baidu Translate and Bing Translator). Second, a questionnaire was designed and completed by 12 Chinese online users (Chinese graduates of a Hispanic Philology major) in order to find out user preferences regarding the collected MT output. Finally, human translation techniques were observed and analyzed to identify what translation techniques would be observed more often in the preferred MT proposals. The result reveals that the MT output of the Chinese gastronomy nomenclature is not of high quality. It would be recommended not to trust the MT in occasions like restaurant menus, TV culinary shows, etc. However, the MT output could be used as an aid for tourists to have a general idea of a dish (the main ingredients, for example). Literal translation turned out to be the most observed technique, followed by borrowing, generalization and adaptation, while amplification, particularization and transposition were infrequently observed. Possibly because that the MT engines at present are limited to relate equivalent terms and offer literal translations without taking into account the whole context meaning of the dish name, which is essential to the application of those less observed techniques. This could give insight into the post-editing of the Chinese dish name translation. By observing and analyzing translation techniques in the proposals of the machine translators, the post-editors could better decide which techniques to apply in each case so as to correct mistakes and improve the quality of the translation.Keywords: Chinese dish names, cultural references, machine translation, translation techniques
Procedia PDF Downloads 1262367 Energy Management Method in DC Microgrid Based on the Equivalent Hydrogen Consumption Minimum Strategy
Authors: Ying Han, Weirong Chen, Qi Li
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An energy management method based on equivalent hydrogen consumption minimum strategy is proposed in this paper aiming at the direct-current (DC) microgrid consisting of photovoltaic cells, fuel cells, energy storage devices, converters and DC loads. The rational allocation of fuel cells and battery devices is achieved by adopting equivalent minimum hydrogen consumption strategy with the full use of power generated by photovoltaic cells. Considering the balance of the battery’s state of charge (SOC), the optimal power of the battery under different SOC conditions is obtained and the reference output power of the fuel cell is calculated. And then a droop control method based on time-varying droop coefficient is proposed to realize the automatic charge and discharge control of the battery, balance the system power and maintain the bus voltage. The proposed control strategy is verified by RT-LAB hardware-in-the-loop simulation platform. The simulation results show that the designed control algorithm can realize the rational allocation of DC micro-grid energy and improve the stability of system.Keywords: DC microgrid, equivalent minimum hydrogen consumption strategy, energy management, time-varying droop coefficient, droop control
Procedia PDF Downloads 2952366 A Study on Evaluation for Performance Verification of Ni-63 Radioisotope Betavoltaic Battery
Authors: Youngmok Yun, Bosung Kim, Sungho Lee, Kyeongsu Jeon, Hyunwook Hwangbo, Byounggun Choi
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A betavoltaic battery converts nuclear energy released as beta particles (β-) directly into electrical energy. Betavoltaic cells are analogous to photovoltaic cells. The beta particle’s kinetic energy enters a p-n junction and creates electron-hole pairs. Subsequently, the built-in potential of the p-n junction accelerates the electrons and ions to their respective collectors. The major challenges are electrical conversion efficiencies and exact evaluation. In this study, the performance of betavoltaic battery was evaluated. The betavoltaic cell was evaluated in the same condition as radiation from radioactive isotope using by FE-SEM(field emission scanning electron microscope). The average energy of the radiation emitted from the Ni-63 radioisotope is 17.42 keV. FE-SEM is capable of emitting an electron beam of 1-30keV. Therefore, it is possible to evaluate betavoltaic cell without radioactive isotopes. The betavoltaic battery consists of radioisotope that is physically connected on the surface of Si-based PN diode. The performance of betavoltaic battery can be estimated by the efficiency of PN diode unit cell. The current generated by scanning electron microscope with fixed accelerating voltage (17keV) was measured by using faraday cup. Electrical characterization of the p-n junction diode was performed by using Nano Probe Work Station and I-V measurement system. The output value of the betavoltaic cells developed by this research team was 0.162 μw/cm2 and the efficiency was 1.14%.Keywords: betavoltaic, nuclear, battery, Ni-63, radio-isotope
Procedia PDF Downloads 2492365 An Experimental Study on the Effect of Operating Parameters during the Micro-Electro-Discharge Machining of Ni Based Alloy
Authors: Asma Perveen, M. P. Jahan
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Ni alloys have managed to cover wide range of applications such as automotive industries, oil gas industries, and aerospace industries. However, these alloys impose challenges while using conventional machining technologies. On the other hand, Micro-Electro-Discharge machining (micro-EDM) is a non-conventional machining method that uses controlled sparks energy to remove material irrespective of the materials hardness. There has been always a huge interest from the industries for developing optimum methodology and parameters in order to enhance the productivity of micro-EDM in terms of reducing machining time and tool wear for different alloys. Therefore, the aims of this study are to investigate the effects of the micro-EDM process parameters, in order to find their optimal values. The input process parameters include voltage, capacitance, and electrode rotational speed, whereas the output parameters considered are machining time, entrance diameter of hole, overcut, tool wear, and crater size. The surface morphology and element characterization are also investigated with the use of SEM and EDX analysis. The experimental result indicates the reduction of machining time with the increment of discharge energy. Discharge energy also contributes to the enlargement of entrance diameter as well as overcut. In addition, tool wears show reduction with the increase of discharge energy. Moreover, crater size is found to be increased in size along with the increment of discharge energy.Keywords: micro holes, micro EDM, Ni Alloy, discharge energy
Procedia PDF Downloads 2702364 Combination of Electrochemical Impedance Spectroscopy and Electromembrane Extraction for the Determination of Zolpidem Using Modified Screen-Printed Electrode
Authors: Ali Naeemy, Mir Ghasem Hoseini
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In this study, for the first time, an analytical method developed and validated by combining electrochemical impedance spectroscopy and electromembrane extraction (EIS-EME) by Vulcan/poly pyrrole nanocomposite modified screen-printed electrode (PPY–VU/SPE) for accurately quantifying zolpidem. EME parameters optimized, including solvent composition, voltage, pH adjustments and extraction time. Zolpidem was transferred from a donor solution (pH 5) to an acceptor solution (pH 13) using a hollow fiber in 1-octanol as a membrane, driven by a 60 V voltage for 25 minutes, ensuring precise and selective extraction. In comparison with SPE, VU/SPE and PPY/SPE, the PPY–VU/SPE was much more efficient for ZP oxidation. Calibration curves with good linearity were obtained in the concentration range of 2-75 µmol L-1 using the EIS-EME with the detection limit of 0.5 µmol L-1 . Finally, the EIS-EME by using the PPY– VU/SPE was successfully used to determine ZP in tablet dosage form, urine and plasma samples. Keywords: Electrochemical impedance spectroscopy, Electromembrane extraction, Zolpidem, Vulcan, poly pyrrole, Screen printed electrodeKeywords: electrochemical impedance spectroscopy, electromembrane extraction, screen printed electrode, zolpidem
Procedia PDF Downloads 272363 GaAs Based Solar Cells: Growth, Fabrication, and Characterization
Authors: Hülya Kuru Mutlu, Mustafa Kulakcı, Uğur Serincan
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The sun is one of the latest developments in renewable energy sources, which has a variety of application. Solar energy is the most preferred renewable energy sources because it can be used directly, it protects the environment and it is economic. In this work, we investigated that important parameter of GaAs-based solar cells with respect to the growth temperature. The samples were grown on (100) oriented p-GaAs substrates by solid source Veeco GEN20MC MBE system equipped with Ga, In, Al, Si, Be effusion cells and an Arsenic cracker cell. The structures of the grown samples are presented. After initial oxide desorption, Sample 1 and Sample 2 were grown at about 585°C and 535°C, respectively. From the grown structures, devices were fabricated by using the standard photolithography procedure. Current-voltage measurements were performed at room temperature (RT). It is observed that Sample 1 which was grown at 585°C has higher efficiency and fill factor compared to Sample 2. Hence, it is concluded that the growth temperature of 585°C is more suitable to grow GaAs-based solar cells considering our samples used in this study.Keywords: molecular beam epitaxy, solar cell, current-voltage measurement, Sun
Procedia PDF Downloads 4662362 Two Steady States and Two Movement Patterns under the Balanced Budget Rule: An Economy with Divisible Labor
Authors: Fujio Takata
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When governments levy taxes on labor income on the basis of a balanced budget rule, two steady states in an economy exist, of which one can cause two movement patterns, namely, indeterminacy paths and a saddle path. However, in this paper, we assume an economy with divisible labor, in which labor adjustment is made by an intensive margin. We demonstrate that there indeed exist the two paths in the economy and that there exists a critical condition dividing them. This is proved by establishing the relationship between a finite elasticity of labor with regard to real wages and the share of capital in output. Consequently, we deduce the existence of an upper limit in the share of capital in output for indeterminacy to occur. The largest possible value of that share is less than 0.5698.Keywords: balanced budget rule, divisible labor, labor income taxation, two movement patterns
Procedia PDF Downloads 1572361 X-Ray Dosimetry by a Low-Cost Current Mode Ion Chamber
Authors: Ava Zarif Sanayei, Mustafa Farjad-Fard, Mohammad-Reza Mohammadian-Behbahani, Leyli Ebrahimi, Sedigheh Sina
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The fabrication and testing of a low-cost air-filled ion chamber for X-ray dosimetry is studied. The chamber is made of a metal cylinder, a central wire, a BC517 Darlington transistor, a 9V DC battery, and a voltmeter in order to have a cost-effective means to measure the dose. The output current of the dosimeter is amplified by the transistor and then fed to the large internal resistance of the voltmeter, producing a readable voltage signal. The dose-response linearity of the ion chamber is evaluated for different exposure scenarios by the X-ray tube. kVp values 70, 90, and 120, and mAs up to 20 are considered. In all experiments, a solid-state dosimeter (Solidose 400, Elimpex Medizintechnik) is used as a reference device for chamber calibration. Each case of exposure is repeated three times, the voltmeter and Solidose readings are recorded, and the mean and standard deviation values are calculated. Then, the calibration curve, derived by plotting voltmeter readings against Solidose readings, provided a linear fit result for all tube kVps of 70, 90, and 120. A 99, 98, and 100% linear relationship, respectively, for kVp values 70, 90, and 120 are demonstrated. The study shows the feasibility of achieving acceptable dose measurements with a simplified setup. Further enhancements to the proposed setup include solutions for limiting the leakage current, optimizing chamber dimensions, utilizing electronic microcontrollers for dedicated data readout, and minimizing the impact of stray electromagnetic fields on the system.Keywords: dosimetry, ion chamber, radiation detection, X-ray
Procedia PDF Downloads 592360 Diagnostic of Breakdown in High Voltage Bushing Power Transformer 500 kV Cirata Substation
Authors: Andika Bagaskara, Andhika Rizki Pratama, Lalu Arya Repatmaja, Septhian Ditaputra Raharja
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The power transformer is one of the critical things in system transmission. Regular testing of the power transformer is very important to maintain the reliability of the power. One of the causes of the failure of the transformer is the breakdown of insulation caused by the presence of voids in the equipment that is electrified. As a result of the voids that occur in this power transformer equipment, it can cause partial discharge. Several methods were used to determine the occurrence of damage to the power transformer equipment, such as Sweep Frequency Response Analysis (SFRA) and Tan Delta. In Inter Bus Transformer (IBT) 500/150 kV Cirata Extra High Voltage (EHV) Substation, a breakdown occurred in the T-phase tertiary bushing. From the lessons learned in this case, a complete electrical test was carried out. From the results of the complete electrical test, there was a suspicion of deterioration in the post-breakdown SFRA results. After overhaul and inspection, traces of voids were found on the tertiary bushing, which indicated a breakdown in the tertiary bushing of the IBT 500/150kV Cirata Substation transformer.Keywords: void, bushing, SFRA, Tan Delta
Procedia PDF Downloads 1212359 Stand Alone Multiple Trough Solar Desalination with Heat Storage
Authors: Abderrahmane Diaf, Kamel Benabdellaziz
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Remote arid areas of the vast expanses of the African deserts hold huge subterranean reserves of brackish water resources waiting for economic development. This work presents design guidelines as well as initial performance data of new autonomous solar desalination equipment which could help local communities produce their own fresh water using solar energy only and, why not, contribute to transforming desert lands into lush gardens. The output of solar distillation equipment is typically low and in the range of 3 l/m2/day on the average. This new design with an integrated, water-based, environmentally-friendly solar heat storage system produced 5 l/m2/day in early spring weather. Equipment output during summer exceeded 9 liters per m2 per day.Keywords: multiple trough distillation, solar desalination, solar distillation with heat storage, water based heat storage system
Procedia PDF Downloads 4312358 A Comparative Study of the Proposed Models for the Components of the National Health Information System
Authors: M. Ahmadi, Sh. Damanabi, F. Sadoughi
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National Health Information System plays an important role in ensuring timely and reliable access to Health information which is essential for strategic and operational decisions that improve health, quality and effectiveness of health care. In other words, by using the National Health information system you can improve the quality of health data, information and knowledge used to support decision making at all levels and areas of the health sector. Since full identification of the components of this system for better planning and management influential factors of performance seems necessary, therefore, in this study, different attitudes towards components of this system are explored comparatively. Methods: This is a descriptive and comparative kind of study. The society includes printed and electronic documents containing components of the national health information system in three parts: input, process, and output. In this context, search for information using library resources and internet search were conducted and data analysis was expressed using comparative tables and qualitative data. Results: The findings showed that there are three different perspectives presenting the components of national health information system, Lippeveld, Sauerborn, and Bodart Model in 2000, Health Metrics Network (HMN) model from World Health Organization in 2008 and Gattini’s 2009 model. All three models outlined above in the input (resources and structure) require components of management and leadership, planning and design programs, supply of staff, software and hardware facilities, and equipment. In addition, in the ‘process’ section from three models, we pointed up the actions ensuring the quality of health information system and in output section, except Lippeveld Model, two other models consider information products, usage and distribution of information as components of the national health information system. Conclusion: The results showed that all the three models have had a brief discussion about the components of health information in input section. However, Lippeveld model has overlooked the components of national health information in process and output sections. Therefore, it seems that the health measurement model of network has a comprehensive presentation for the components of health system in all three sections-input, process, and output.Keywords: National Health Information System, components of the NHIS, Lippeveld Model
Procedia PDF Downloads 4122357 Power Quality Modeling Using Recognition Learning Methods for Waveform Disturbances
Authors: Sang-Keun Moon, Hong-Rok Lim, Jin-O Kim
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This paper presents a Power Quality (PQ) modeling and filtering processes for the distribution system disturbances using recognition learning methods. Typical PQ waveforms with mathematical applications and gathered field data are applied to the proposed models. The objective of this paper is analyzing PQ data with respect to monitoring, discriminating, and evaluating the waveform of power disturbances to ensure the system preventative system failure protections and complex system problem estimations. Examined signal filtering techniques are used for the field waveform noises and feature extractions. Using extraction and learning classification techniques, the efficiency was verified for the recognition of the PQ disturbances with focusing on interactive modeling methods in this paper. The waveform of selected 8 disturbances is modeled with randomized parameters of IEEE 1159 PQ ranges. The range, parameters, and weights are updated regarding field waveform obtained. Along with voltages, currents have same process to obtain the waveform features as the voltage apart from some of ratings and filters. Changing loads are causing the distortion in the voltage waveform due to the drawing of the different patterns of current variation. In the conclusion, PQ disturbances in the voltage and current waveforms indicate different types of patterns of variations and disturbance, and a modified technique based on the symmetrical components in time domain was proposed in this paper for the PQ disturbances detection and then classification. Our method is based on the fact that obtained waveforms from suggested trigger conditions contain potential information for abnormality detections. The extracted features are sequentially applied to estimation and recognition learning modules for further studies.Keywords: power quality recognition, PQ modeling, waveform feature extraction, disturbance trigger condition, PQ signal filtering
Procedia PDF Downloads 177