106 research outputs found

    Assessment of Energy Systems Using Extended Fuzzy AHP, Fuzzy VIKOR, and TOPSIS Approaches to Manage Non-Cooperative Opinions

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    Energy systems planning commonly involves the study of supply and demand of power, forecasting the trends of parameters established on economics and technical criteria of models. Numerous measures are needed for the fulfillment of energy system assessment and the investment plans. The higher energy prices which call for diversification of energy systems and managing the resolution of conflicts are the results of high energy demand for growing economies. Due to some challenging problems of fossil fuels, energy production and distribution from alternative sources are getting more attention. This study aimed to reveal the most proper energy systems in Saudi Arabia for investment. Hence, integrated fuzzy AHP (Analytic Hierarchy Process), fuzzy VIKOR (Vlse Kriterijumska Optimizacija Kompromisno Resenje) and TOPSIS (Technique for Order Preferences by Similarity to Idle Solution) methodologies were employed to determine the most eligible energy systems for investment. Eight alternative energy systems were assessed against nine criteriaÔÇöpower generation capacity, efficiency, storability, safety, air pollution, being depletable, net present value, enhanced local economic development, and government support. Data were collected using the Delphi method, a team of three decision-makers (DMs) was established in a heterogeneous manner with the addition of nine domain experts to carry out the analysis. The fuzzy AHP approach was used for clarifying the weight of criteria and fuzzy VIKOR and TOPSIS were utilized for ordering the alternative energy systems according to their investment priority. On the other hand, sensitivity analysis was carried out to determine the priority of investment for energy systems and comparison of them using the weight of group utility and fuzzy DEA (Data Envelopment Analysis) approaches. The results and findings suggested that solar photovoltaic (PV) is the paramount renewable energy system for investment, according to both fuzzy VIKOR and fuzzy TOPSIS approaches. In this context our findings were compared with other works comprehensively.This research was funded by the Deanship of Scientific Research (DSR) at King Abdulaziz University, Jeddah, under grant no. (RG-7-135-38). The authors, therefore, acknowledge with thanks DSR technical and financial support

    Application of feature extraction and artificial intelligence techniques for increasing the accuracy of x-ray radiation based two phase flow meter

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    The increasing consumption of fossil fuel resources in the world has placed emphasis on flow measurements in the oil industry. This has generated a growing niche in the flowmeter industry. In this regard, in this study, an artificial neural network (ANN) and various feature extractions have been utilized to enhance the precision of X-ray radiation-based two-phase flowmeters. The detection system proposed in this article comprises an X-ray tube, a NaI detector to record the photons, and a Pyrex-glass pipe, which is placed between detector and source. To model the mentioned geometry, the Monte Carlo MCNP-X code was utilized. Five features in the time domain were derived from the collected data to be used as the neural network input. Multi-Layer Perceptron (MLP) was applied to approximate the function related to the input-output relationship. Finally, the introduced approach was able to correctly recognize the flow pattern and predict the volume fraction of two-phase flowÔÇÖs components with root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) of less than 0.51, 0.4 and 1.16%, respectively. The obtained precision of the proposed system in this study is better than those reported in previous works

    Designing a Solar Photovoltaic System for Generating Renewable Energy of a Hospital: Performance Analysis and Adjustment Based on RSM and ANFIS Approaches

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    One of the most favorable renewable energy sources, solar photovoltaic (PV) can meet the electricity demand considerably. Sunlight is converted into electricity by the solar PV systems using cells containing semiconductor materials. A PV system is designed to meet the energy needs of King Abdulaziz University Hospital. A new method has been introduced to find optimal working capacity, and determine the selfÔÇÉconsumption and sufficiency rates of the PV system. Response surface methodology (RSM) is used for determining the optimal working conditions of PV panels. Similarly, an adaptive neural network based fuzzy inference system (ANFIS) was employed to analyze the performance of solar PV panels. The outcomes of methods were compared to the actual outcomes available for testing the performance of models. Hence, for a 40 MW target PV system capacity, the RSM determined that approximately 33.96 MW electricity can be produced, when the radiation rate is 896.3 W/m2, the module surface temperature is 41.4 ┬░C, the outdoor temperature is 36.2 ┬░C, the wind direction and speed are 305.6 and 6.7 m/s, respectively. The ANFIS model (with nine rules) gave the highest performance with lowest residual for the same design parameters. Hence, it was determined that the hourly electrical energy requirement of the hospital can be met by the PV system during the year.Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah, under grant No. (D1441ÔÇÉ135ÔÇÉ626

    Applications of discrete wavelet transform for feature extraction to increase the accuracy of monitoring systems of liquid petroleum products

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    This paper presents a methodology to monitor the liquid petroleum products which pass through transmission pipes. A simulation setup consisting of an X-ray tube, a detector, and a pipe was established using a Monte Carlo n-particle X-version transport code to investigate a two-by-two mixture of four different petroleum products, namely, ethylene glycol, crude oil, gasoline, and gasoil, in deferent volumetric ratios. After collecting the signals of each simulation, discrete wavelet transform (DWT) was applied as the feature extraction system. Then, the statistical feature, named the standard deviation, was calculated from the approximation of the fifth level, and the details of the second to fifth level provide appropriate inputs for neural network training. Three multilayer perceptron neural networks were utilized to predict the volume ratio of three types of petroleum products, and the volume ratio of the fourth product could easily be obtained from the results of the three presented networks. Finally, a root mean square error of less than 1.77 was obtained in predicting the volume ratio, which was much more accurate than in previous research. This high accuracy was due to the use of DWT for feature extraction

    Dexamethasone Implant (Ozurdex) in a Case with Unilateral Simultaneous Central Retinal Vein and Branch Retinal Artery Occlusion

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    Simultaneous branch retinal artery and vein occlusion is a rare condition that may cause severe visual loss, and its treatment is often unrewarding. Herein, we report a case with simultaneous central retinal vein and branch retinal artery occlusion; it was successfully treated with a single dexamethasone intravitreal implant. The affected eye attained a visual acuity level of 20/25 from the visual acuity of hand motions at presentation with a residual, but relatively diminished, altitudinal scotoma during a follow-up period of 6 months

    Central nervous system: overall considerations based on hardware realization of digital spiking silicon neurons (dssns) and synaptic coupling

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    The Central Nervous System (CNS) is the part of the nervous system including the brain and spinal cord. The CNS is so named because the brain integrates the received information and influences the activity of different sections of the bodies. The basic elements of this important organ are: neurons, synapses, and glias. Neuronal modeling approach and hardware realization design for the nervous system of the brain is an important issue in the case of reproducing the same biological neuronal behaviors. This work applies a quadratic-based modeling called Digital Spiking Silicon Neuron (DSSN) to propose a modified version of the neuronal model which is capable of imitating the basic behaviors of the original model. The proposed neuron is modeled based on the primary hyperbolic functions, which can be realized in high correlation state with the main model (original one). Really, if the high-cost terms of the original model, and its functions were removed, a low-error and high-performance (in case of frequency and speed-up) new model will be extracted compared to the original model. For testing and validating the new model in hardware state, Xilinx Spartan-3 FPGA board has been considered and used. Hardware results show the high-degree of similarity between the original and proposed models (in terms of neuronal behaviors) and also higher frequency and low-cost condition have been achieved. The implementation results show that the overall saving is more than other papers and also the original model. Moreover, frequency of the proposed neuronal model is about 168 MHz, which is significantly higher than the original model frequency, 63 MHz

    Comparison of respiratory parameters with and without mouth guard in Karate PlayersKaratecilerde a─č─▒z koruyuculu ve a─č─▒z koruyucusuz ├Âl├ž├╝len solunum parametrelerinin kar┼č─▒la┼čt─▒r─▒lmas─▒

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    This study aimed to examine the effects of using a mouth guard in Karate on respiration parameters. The study sample consisted of 10 volunteer elite male karate athletes who participated in the National Karate Team and still practice the sport (24.4┬▒6.3years, 176.2┬▒7.4 cm, 71┬▒4.1 kg). The athletes were exposed to respiration tests without and with mouth guard with 2 days interval that give FVC, FEV1, MVV and PEF values. In the light of the found parameters, were no meaningful differences were observed in measurements of parameters between the measurements with and without a mouth guard (p > 0.05).┬á The athletes continued their routine training between pre-test and post-test. In conclusion it was seen that the use of mouth guard did not directly affect the breathing performance.Extended English abstract is in the end of Full Text┬áPDF (TURKISH)┬áfile.├ľzetBu ├žal─▒┼čmada Karate sporundaki a─č─▒z koruyucusu kullan─▒m─▒n─▒n solunum parametrelerine etkisini incelemek ama├žlanm─▒┼čt─▒r. ├çal─▒┼čmaya Karate Milli Tak─▒m─▒ÔÇÖnda yer alm─▒┼č ve aktif spor ya┼čant─▒s─▒ devam eden g├Ân├╝ll├╝ 10 erkek elit karate sporcusu (24,4┬▒6,3y─▒l, 176,2┬▒7,4 cm, 71┬▒4,1 kg) dahil edilmi┼čtir. Sporcular FVC, FEV1 MVV, PEF de─čerlerinin elde edildi─či solunum testlerine 2 g├╝n ara ile di┼čliksiz ve di┼člikli olarak kat─▒lm─▒┼čt─▒r. Kaydedilen parametreler ─▒┼č─▒─č─▒nda,┬á di┼člikli ve di┼čliksiz ├Âl├ž├╝mler aras─▒nda istatistiksel a├ž─▒dan anlaml─▒ bir ili┼čki g├Âzlenmemi┼čtir (p > 0.05). Sporcular ├Ân test ve son test aras─▒ rutin antrenmanlar─▒na devam etmi┼čtir. ┬áSonu├ž olarak, di┼člik kullan─▒m─▒n─▒n solunum performans─▒n─▒ direkt olarak etkilemedi─či g├Âr├╝lm├╝┼čt├╝r

    Mutations in Influenza A Virus (H5N1) and Possible Limited Spread, Turkey, 2006

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    We report mutations in influenza A virus (H5N1) strains associated with 2 outbreaks in Turkey. Four novel amino acid changes (Q447L, N556K, and R46K in RNA polymerase and S133A in hemagglutinin) were detected in virus isolates from 2 siblings who died
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