This paper addresses an asset management problem in the context of the wind energy industry. Asset management decisions (including operation and maintenance, retrofitting and purchasing) for assets reached their end-of-life are explicitly examined in a linear programming model over a planning horizon. Unfortunately, almost all important generic classes of integer programming problems are NP-hard and many of these problems are large-size. Therefore, in order to solve practical integer programming problems we may need to use problem specific algorithms which can exploit some special structures of the problem at hand. We propose a solution approach based on a lagrangian relaxation and the subgradient method for a large size parallel asset management problem, which originally solved by using mixed integer linear programming (MILP). The decomposition approach considers the relaxation of different sets of constraints, including the budget and energy constraints. The computational results show that the incorporation of langrangian relaxation significantly improves the duality gap and solution time of a case study from wind turbine (WT) sector
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In this study, the effect of dielectric barrier discharge vortex generator (DBD VGs) plasma actuators on pressure coefficients of a NACA2415 airfoil are investigated experimentally at low Reynolds number. The DBD plasma VGs are placed at the leading edge of the airfoil (x/C=0.1). Force measurements with a six-axis load cell and pressure measurements with a pitot static tube are conducted. The pressure distributions over the airfoil are measured using a scan-valve unit and a pressure transducer. The experimental results showed that when the dielectric barrier discharge vortex generators were driven at a specific electrical parameter, the lift coefficient of the airfoil is increased significantly and the stall angle was postponed by induced flow effect. Moreover, the co-rotating dielectric barrier discharge vortex generators type is more effective than the counter-rotating type in reducing the drag coefficient. Furthermore, the 3D flow structure for both types of vortex generators was observed at the surface of the airfoil by using pressure measurements along with spanwise direction. In addition, it appears that the effect is less in the case of the stall angle in both plasma actuated state for drag coefficient, but they are more effective in the pre-stall angle and post-stall cases.
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Bu çalışmada gerçek zamanlı DNA dizilemesi sağlayan, düşük maliyetli vetaşınabilir bir yeni nesil dizileme teknolojisi olan nanogözenek dizilemeteknolojisini kullanarak gerçek zamanlı ve düşük maliyetli patojen/etken tespitalgoritmaları sunulmaktadır. Çalışma kapsamında Oxford Nanopore MinION DNAdizileyicisi ile sekanslanan bakterileri gerçek zamanlı tanıyabilecek bilgi kuramıtemelli biyoinformatik teşhis algoritmaları geliştirilmiş ve performansları gerçekveri üzerinde test edilmiştir. Taksona özgü oligomer karakterizasyonunu sağlayanBağıl Bolluk Endeksleri (ing: Relative Abundance Index-RAI) ve nükleotid dizileriiçindeki korelasyonları ortaya seren Ortalama Karşılıklı Bilgi (OKB) yöntemi ile DNAkarakterizasyonu yapılarak patojen tanıma algoritmaları geliştirilmiştir. Tasarlanansimülasyonlar ile ortalama teşhis koyma süreleri ve doğrulukları hakkındakiistatistikler elde edilerek bu yönde oluşturulacak sistemlerin rutin kullanım içinfizibilitesi ortaya konmuştur. Önerilen OKB profili ve RAI tabanlı algoritmaların hızlıpatojen tanıma konusunda yeterli doğruluk seviyesinde ve kısa sürede tanımayapabilecek hızda olduğu ve mevcut programlarla rekabet edebilen performanstaolduğu nanogözenek dizilemesi yapılan patojen paneli üzerinde gösterilmiştir.Geliştirilen yöntem kısıtlı bir patojen paneli üzerinde etkinlik göstermektedir; busebeple geniş çaplı kullanım için daha ileri çalışmaların yürütülmesi gerekmektedir.
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Bu çalışmada, Kayseri ili tramvay hattı boyunca meydana gelen trafik kazaları , oluş nedenleri, meydana geliş zamanı, ve kazaya karışanlar açısından veri madenciliği yöntemleri ile incelenmiştir.
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In this study, we aimed to determine the toxic effect of increasing doses ofBendiocarb, an insecticide from the carbamate group, on human blood cells in vitro viaby Comet test, determination of total antioxidant capacity, antioxidant enzyme activityand malondialdehyde (MDA) level. Leukocyte isolation was performed from bloodsamples taken from six healthy male individuals who did not smoke and use alcohol andwere not exposed to any chemicals in the working environment, and then theirleukocytes exposed to increasing doses of Bendiocarb (20, 40, 80, 160 µg / mL). Comettest, iron reduction antioxidant capacity (FRAP), 2-2'azinobis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS/TEAC) analysis with superoxide dismutase (SOD), catalase (CAT),glutathione peroxidase (GPx) and MDA were evaluated. At the end of the study, it wasdetermined that antioxidant enzyme levels decreased significantly due to dose increase,whereas MDA levels increased significantly in all doses (p<0.05). According to FRAP andTEAC methods, the antioxidant capacity of blood cells decreased significantly inincreasing doses of Bendiocarb compared to the control group (p<0.05). In the Comettest, DNA tail percentage, length and moment were increased significantly in increasingdoses of Bendiocarb and DNA damage was detected (p<0.05). This study is a preliminarystudy on this subject, and it has been shown in our study that the uncontrolled use ofBendiocarb pesticide in nature will have harmful effects on the environment and livingthings. We believe that the research will contribute to the literature and shed light onfuture comprehensive studies.
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In this research, we produce a homothetic motion in 𝐸1𝑛 from a homothetic motion in 𝐸𝑛 by using a dual transformation. Furthermore, we define a transition from Euclidean umbrella matrix to Lorentzian umbrella matrix. Then, we examine the invariance of the axis of the umbrella motion that is 𝑥⃗=(1,1,..,1) in both spaces. We also provide examples to make our results clear. Moreover, we draw their figures to investigate visual representations. Finally, we study on homothetic motions in dual spaces.
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In this study, stone samples taken from volcanic tuffs at seven different locations in the Cappadocia region were examined. In order to obtain the powder diffraction pattern of the samples, they were pulverized by grinding in agate mortar. Diffraction patterns were taken on a Bruker AXS D8 Advance Model diffractometer. Qualitative analysis of the pattern data was performed using the XRD Evolution program. The most common compounds as a result of the analysis: it has been identified as Silicon Oxide [SiO2], Magnesium Silicate Hydroxide [Mg3(Si2O5)(OH)4], Sodium Calcium Aluminum Silicate [(Na0.45Ca0.55)(Al1.55Si2.45O8)], Sodium Calcium Magnesium Aluminum Iron Titanium Aluminum Silicon Oxide Hydroxide Hydrate [(Mg2.46Al0.3Fe0.22Ti0.021)2(Mg0.38Ca0.03Na0.02)2((Si2.83 Al1.17)O10)2 (OH)4(H2O)3.4], Potassium Aluminum Silicate Hydroxide [(K, Ca, Na)(Al, Mg, Fe)2(Si, Al)4O10(OH)2], Sodium Magnesium Aluminum Iron Silicon Oxide Hydroxide Hydrate [Na0.930Mg2.810Fe0.065Al1.185Si2.895O10(OH)2 (H2O)3], Calcium Magnesium Aluminum Silicate Hydroxide Hydrate [Ca0.2 (Al, Mg)2Si4O10(OH)2.xH2O].
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With the developments of communication technology, the number of wireless devices is increasing day by day. Fifth generation (5G) has an important place in the communication of these devices. Different technologies have been proposed to fulfill the requirements of 5G standards. Among these technologies, Large Intelligent Surfaces (LIS) promise the future for the realization of 5G technology. LIS are the communication technology whose name has been heard recently. In this paper, the topic of LIS has been discussed with considering some scenarios different fading channels. Furthermore, performance analysis has been performed over Rician and Weibull fading channels by considering the computer programmed application of LIS. A comparison of dual-hop (DH) and access point (AP) types, which are LIS types, was realized. The results were interpreted and new solution proposals were discussed.
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Gradient Boosting Decision Trees (GBDT) algorithms have been proven to be among the best algorithms in machine learning. XGBoost, the most popular GBDT algorithm, has won many competitions on websites like Kaggle. However, XGBoost is not the only GBDT algorithm with state-of-the-art performance. There are other GBDT algorithms that have more advantages than XGBoost and sometimes even more potent like LightGBM and CatBoost. This paper aims to compare the performance of CPU implementation of the top three gradient boosting algorithms. We start by explaining how the three algorithms work and the hyperparameters similarities between them. Then we use a variety of performance criteria to evaluate their performance. We divide the performance criteria into four: accuracy, speed, reliability, and ease of use. The performance of the three algorithms has been tested with five classification and regression problems. Our findings show that the LightGBM algorithm has the best performance of the three with a balanced combination of accuracy, speed, reliability, and ease of use, followed by XGBoost with the histogram method, and CatBoost came last with slow and inconsistent performance.
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In this study, U-shaped fiber optic sensor tips sensitive to refractive index (RI) change were produced, and its performance analyses were carried out. Three sensor tips were used to measure ethanol/methanol-water mixtures in concentrations from 0% to 16.66%. The ethanol sensor tip was able to detect the RI change of 4×10-4 RIU. Its maximum sensitivity is 7.71 mV/RIU, and its linearity is 0.9985. The methanol sensor tip was able to detect the RI change of 1×10-4 RIU. Its maximum sensitivity is 28.49 mV/RIU, and its linearity is 0.9969. Each sensor tips determine the change of 1.41% concentration in the mixtures. Moreover, the results show that it can provide high precision in the measurement of ethanol/methanol-water mixtures and achieve satisfying stability and repeatability.
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