Interpreting of fuzzy dispersion model by contour map method

Akarsularda boyuna dispersiyon katsayısının belirlenmesi için geliştirilen denklemler genellikle doğrusal olmayan regresyon analizine, istatistik metotlara veya benzeri kara kutu yaklaşımlarına dayanmaktadır. Geliştirilmeleri sırasında yapılan kabuller nedeniyle bu denklemler dikkatli kullanılmadıkları taktirde gerçekçi olmayan sonuçlarla karşılaşılabilir. Bu çalışmada bulanık mantık yaklaşımı ile geliştirilen yeni bir modelin, ölçümler sonucu elde edilen verilere uygulanmasının sonuçları sunulmuştur. Veri kümeleri,bağımsız değişkenler olarak akımın derinliği, genişliği, kesit ortalama ve kayma hızlarını, bağımlı değişken olarak da boyuna dispersiyon katsayısını içermektedir. Bulanık model sonuçları, eldeki veriler ve farklı yedi çalışmanın sonuçları kontur harita yöntemi kullanılarak karşılaştırılmış ve bulanık modelin, mevcut çalışmalardan daha gerçekçi sonuçlar verdiği ve kontur harita yönteminin model sonuçlarının karşılaştırılmasında güvenle kullanılabileceği görülmüştür.Anahtar Kelimeler: Boyuna dispersiyon katsayısı, Bulanık mantık, difüzyon, dispersiyon, kontur harita, modelleme.In order to investigate the dispersion process, researchers have used differential equations written under certain assumptions with a dispersion coefficient. These differential equations cannot be used in practice unless the dispersion coefficient is either directly measured or calculated from measurements. Many empirical equations, statistical methods or several black box approaches are used to determine the longitudinal dispersion coefficients in natural channels. The empirical equations most depend procedurally on the least squares techniques through regression equations of non-linear types. Unfortunately, many critical assumptions in the derivation of these regression equations are not considered and consequently the resulting equations can be used with precautious and reservations. Otherwise, the results will not be reliable. The main goal of this study is to apply a new fuzzy model to the 96 data sets concerning more than 30 rivers at different times. The data sets include four independent and one dependent variables, which are, the depth, the width and the mean cross-sectional velocity of the flow, shear velocity and longitudinal dispersion coefficient. Results of the model have been compared with existing data and the results of seven equations using contour map method. It is observed that the fuzzy model yields more reliable results than other approaches and it can be used more easily and efficiently.Keywords: Contour map, dispersion, fuzzy-logic, longitudinal dispersion coefficient, modelin

Modeling, design, and synthesis of gram-scale monodispersed silver nanoparticles using microwave-assisted polyol process for metamaterial applications

High-yield monodispersed silver (Ag) nanospheres were modeled, designed, and synthesized by microwave-assisted (MW-assisted) polyol method from AgNO3, polyvinyl pyrrolidone (PVP), and ethylene glycol (EG), as precursors, at 145 °C within a short reaction time of 2 min, and the results were compared to those of conventional polyol method. Maintaining the PVP:AgNO3 molar ratio, the effect of increasing the amounts of AgNO3 and PVP at a constant amount of EG (40 mL) on the final product was evaluated. The synthesized nanoparticles (NPs) were characterized by SEM, UV–Vis spectroscopy, FTIR and DLS analysis. The results showed that with increasing the amount of AgNO3 to 0.5 and 1 g, monodispersed Ag nanoparticles (Ag NPs) with particle sizes of 54 and 61 nm were formed, as per the plasmon absorption peaks at 436 and 442 nm, respectively. Moreover, using 40 mL of the EG solution, we could obtain a high yield of the NPs (~90%). The sub-gram yield was excellently high, offering great opportunities for commercializing the procedure. Also, the proposed study paves a new way for Ag NPs realization for different practical applications ranging from MW to optics

Targeted dielectric coating of silver nanoparticles with silica to manipulate optical properties for metasurface applications

An epsilon-negative metamaterial (ENM) containing core@shell nanoparticles (NPs) was designed, where silver (Ag) NPs served as core and silica (SiO2) was used as spacer shell. AgNPs were synthesized in large scale, using microwave-assisted polyol method, in three average particle sizes, as 30, 54, and 61nm, with a narrow particle size distribution. Optical absorption of Ag NPs was investigated using UV–Vis spectroscopy. Their optical behavior was also theoretically predicted for different thicknesses of the SiO2 shell immersed in media of different refractive indices using the Clausius - Mossotti equation. Based on the results, optimal outputs were obtained with a SiO2 shell of 10nm in thickness encompassing 54nm Ag NPs based on the analytical model and numerical simulations here developed for core-shell structures. Then 10nm SiO2 shell was grown on 54nm Ag NPs by sol-gel synthesis. The NPs were then characterized by UV–Vis, TEM, SEM, EDX, DLS, and zeta potential analyses. The synthesized core-shell NPs can be used to establish epsilon-negative properties in polymer layers within visible range of wavelengths

Tilly's Technical Accounts and Standard Stories Explored in Financial Markets:The Case of the Istanbul Stock Exchange

In this article, I follow the lead opened up by Tilly (1999, 2002) who was interested in people's storytelling. I do so by looking at sense-making and the legitimacy narratives of market actors in the Istanbul Stock Exchange. Tilly (2006, 2008) himself walked the narrative path and investigated Why and how people give reasons and how people attribute Credit and Blame to other's actions. These books provide insights into people's storytelling in the everyday situations of the home, courtrooms, hospitals, and so on. Nevertheless, Tilly's faith in the prevalence of technical accounts as modes of explanation in intra and inter organisational settings, and superior stories as mode of communication between expert givers and non-specialized receivers, seems to ignore informational uncertainties, intra and inter organisational hierarchies and conflicts pertinent to organisations. It is these factors that push standard stories (Tilly, 1999) into the forefront at the expense of technical stories within the story exchanges of market actors. I demonstrate this by presenting a sample of story exchanges from the Istanbul Stock Exchange under situations of informational uncertainties and organisational conflicts

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Impact of clinical phenotypes on management and outcomes in European atrial fibrillation patients: a report from the ESC-EHRA EURObservational Research Programme in AF (EORP-AF) General Long-Term Registry

Background: Epidemiological studies in atrial fibrillation (AF) illustrate that clinical complexity increase the risk of major adverse outcomes. We aimed to describe European AF patients\u2019 clinical phenotypes and analyse the differential clinical course. Methods: We performed a hierarchical cluster analysis based on Ward\u2019s Method and Squared Euclidean Distance using 22 clinical binary variables, identifying the optimal number of clusters. We investigated differences in clinical management, use of healthcare resources and outcomes in a cohort of European AF patients from a Europe-wide observational registry. Results: A total of 9363 were available for this analysis. We identified three clusters: Cluster 1 (n = 3634; 38.8%) characterized by older patients and prevalent non-cardiac comorbidities; Cluster 2 (n = 2774; 29.6%) characterized by younger patients with low prevalence of comorbidities; Cluster 3 (n = 2955;31.6%) characterized by patients\u2019 prevalent cardiovascular risk factors/comorbidities. Over a mean follow-up of 22.5 months, Cluster 3 had the highest rate of cardiovascular events, all-cause death, and the composite outcome (combining the previous two) compared to Cluster 1 and Cluster 2 (all P <.001). An adjusted Cox regression showed that compared to Cluster 2, Cluster 3 (hazard ratio (HR) 2.87, 95% confidence interval (CI) 2.27\u20133.62; HR 3.42, 95%CI 2.72\u20134.31; HR 2.79, 95%CI 2.32\u20133.35), and Cluster 1 (HR 1.88, 95%CI 1.48\u20132.38; HR 2.50, 95%CI 1.98\u20133.15; HR 2.09, 95%CI 1.74\u20132.51) reported a higher risk for the three outcomes respectively. Conclusions: In European AF patients, three main clusters were identified, differentiated by differential presence of comorbidities. Both non-cardiac and cardiac comorbidities clusters were found to be associated with an increased risk of major adverse outcomes