500 KW Rüzgar Türbini İçin Ana Şaft Tasarımı Ve Analizi

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Bu çalışmada, 500 kW güç üreten bir rüzgar türbinin ana şaftının tasarımı ve yapısal analizleri yapılmıştır. Ana şaftın boyutlandırılmasında yorulma kriterlerinin esas alınması gerekmektedir. Ana şaftın yorulmaya ait yük durumu ise literatürde bulunan ampirik formüller kullanılarak hesaplanmıştır. Yorulma analizlerinde şaftı çevrimsel yüklerle zorlayan rotor ağırlığının yanında rüzgar kesmesi ve kule blokaj etkisi vb. sebeplerle ortaya çıkan değişken eğilme momenti ve tork değerleri de hesaba katılmıştır. Ana şaftın kritik kesitlerindeki çap hesabı, ASME Eliptik yorulma kriteri kullanılarak sonsuz ömre göre yapılmıştır. Ana şaftın tasarımındaki kritik bölgeler şaftın yataklandığı bölge ve şaftın dişli kutusuna bağlandığı bölgedir. Ayrıca, kontrol amaçlı olarak Uluslararası Elektroteknik Komisyonu’nun (International Electrotechnical Commision) yayınlamış olduğu IEC 64100-1 standardında belirtilen yükleme şartları için ana şaftın statik analizleri ANSYS 14.5 sonlu elemanlar yazılımı kullanılarak gerçekleştirilmiştir. Şaftın sonlu eleman modeli SOLID185 elemanlar kullanılarak oluşturulmuştur. Ayrıca, ana şaft - göbek bağlantı elemanlarının analizi de bu çalışma kapsamında yapılmıştır. Sayısal ve analitik yöntemler kullanılarak elde edilen deformasyon ve gerilme sonuçları karşılaştırılmış ve iyi bir uyum olduğu görülmüştür.In this paper, the main shaft which is one of the important structural parts for a 500 kW wind turbine has been designed. The fatigue criteria has been based on sizing the main shaft. The main shafts critic desing loads have been calculated by empirical formulas which are on the literatures. Oscillation moments of the torque and the flexural moments which is created by wind share, and effect of tower, etc. have been envisaged for analytical and numerical studies. In this study, the main shaft has been designed for infinite life using with ASME Elliptic criteria. There are two critic areas which are supported and connected to the gear box. In addition Iternational Electrotechnical Commision (IEC) 64100-1 standards have been based on the critic design load cases. The main shaft and the fasteners are modeled using the finite element method. The finite element model of the shaft is designed using with SOLID185 elements. Its static analysis have been achieved with using ANSYS 14.5 software. Also a comparison of two different approximations have been mentioned in this paper. The values of analitic and numerical of deplacement and stress are compared each

Attitude of the school of fine arts and sportschools students in the sport departments towards the quantitative classes (Sample Elazig)

Tutum ve davranış, genelde bir kimsenin ele alınan bir nesneye, bir duruma ya da olaya karşı olan olumlu veya olumsuz tavrı olarak kabul edilir. Bu bağlamda eğitim ise, bireyleri ve toplumları amaçlı, düzgün bir yaşam biçimine ulaştırma; sahip olunan bilgi, beceri ve değerleri planlı bir şekilde bir sonraki kuşağa aktarma ve bu arada insan davranışlarını yaşantılar yoluyla değiştirme süreci olarak ifade edilir. Öğrencinin olumlu bir tutum kazanmasında, başarı kimliğini geliştirmesinde, değişim odağının kendisi olduğunu fark etmesinde tutum ve davranışlarının etkisi büyüktür. Bu çalışmanın amacı, Güzel Sanatlar ve Spor Liseleri spor bölümü öğrencilerinin fen ve matematik derslerine karşı tutumlarının tespit edilmesini sağlamaktır. Araştırmanın evreni, Güzel Sanatlar ve Spor Liseleri spor bölümü öğrencileridir. Örneklemi Elazığ Güzel Sanatlar ve Spor Lisesinde yapılmış ; 73’ ü erkek , 43’ ü kız toplam 116 öğrenci araştırmaya konu edilmiştir. Araştırma sonunda veriler SPSS 15.0 programında analiz edilmiş, verilerin istatistiki anlamda geçerliliği için 0,05 anlamlılık düzeyi kabul edilmiştir. Sonuç olarak bu çalışmada; öğrencilerin, fizik ve matematik gibi sayısal derslerin zor olduğu düşüncesinden hareketle ‘Ben zaten başarılı olamam!’ önyargısını taşıdıkları görülmüştür. Bu anlayış onların derslere karşı olan ilgisizliğine ve dolayısıyla başarısızlıklarına zemin hazırlamıştır. Araştırma sonuçlarından biri de müsabakalar öncesindeki hazırlanma dönemleri ile il dışı turnuvalara katılımların öğrencilerin sayısal derslerdeki motivasyonlarını olumsuz olarak etkilediği gerçeğidir.Attitudes and behaviours are usually considered as a positive or negative attitude towards an object which is dealt with, a situation or an event of any person. And the education in this context, however, can be expressed as a process of taking forward the individuals and the communities to a proper way of life with a purpose and of conveying the attained knowledge, skills and values in a planned way to the next generation and in the meantime as the changing process of the human behaviours through experiences. The behaviours of teachers have a significant impact in having the students gain a positive attitude, in developing their success identity, in having the student be aware that s/he himself is the centre of the change. The purpose of this study is to determine the attitudes of the students of sports departments at Fine Arts and Sports High Schools towards the science and mathematics classes. The population of the study are the students of the Sports departments at the Fine Arts and Sports High Schools. And the sampling are the Elazig Fine Arts and Sports High School, the total of 116 persons, of which 73 per cent were male and 43 per cent were female students. At the end of the research the data were analysed using SPSS 15.0 program, and the significance level of 0.05 was adopted for the validity of the data in statistical terms. As a result of this study, it was observed that the students in general were prejudiced against science and math classes with the idea that they could not be successful. In addition, based on the idea that the courses were difficult, it was observed that they also were indifferent towards these courses. It was understood that preparing for sports competitions and going out of the province for tournaments, negatively affected their motivation in the quantitative classes

Ambient synthesis of nanomaterials by in situ heterogeneous metal/ligand reactions

Coordination polymers are ideal synthons in creating high aspect ratio nanostructures, however, conventional synthetic methods are often restricted to batch-wise and costly processes. Herein, we demonstrate a non-traditional, frugal approach to synthesize 1D coordination polymers by in situ etching of zerovalent metal particle precursors. This procedure is denoted as the heterogeneous metal/ligand reaction and was demonstrated on Group 13 metals as a proof of concept. Simple carboxylic acids supply the etchant protons and ligands for metal ions (conjugate base) in a 1 : 1 ratio. This scalable reaction produces a 1D polymer that assembles into high-aspect ratio 'nanobeams'. We demonstrate control over crystal structure and morphology by tuning the: (i) metal center, (ii) stoichiometry and (iii) structure of the ligands. This work presents a general scalable method for continuous, heat free and water-based coordination polymer synthesis

High trophic similarity between non-native common carp and gibel carp in Turkish freshwaters: Implications for management

Although the detrimental ecological and economic effects of introducing freshwater fish species have been extensively documented, non-native freshwater fishes continue to be introduced in large numbers globally to enhance fisheries and aquaculture. In Turkey, stocking of common carp Cyprinus carpio is practised to provide food security for people and job security for artisanal fishers, resulting in a country-wide distribution. These stockings, however, increase the risk of accidental introductions and have led to introductions and subsequent invasions of gibel carp Carassius gibelio, a globally invasive and highly detrimental fish species. Here, we assessed the growth types, body conditions and trophic interactions via bulk carbon and nitrogen stable isotope analysis of common and gibel carp in both natural and artificial water bodies in Turkey. The results indicated that common and gibel carp express similar growth types and body conditions in all waters and have similar trophic ecologies. This leads to substantial trophic niche overlaps in waters where they co-occur, with the potential for strong interspecific competition. Considering the ongoing stocking of common carp for fishery enhancement, we recommend to specifically target these stockings in waters where gibel carp has already become invasive. Our findings, indeed, suggest that common carp releases have the potential to hamper invasive gibel carp populations by increasing the competitive interactions between the two species

Sex-specific microglia state in the neuroligin-4 knock-out mouse model of autism spectrum disorder

Neuroligin-4 (NLGN4) loss-of-function mutations are associated with monogenic heritable autism spectrum disorder (ASD) and cause alterations in both synaptic and behavioral phenotypes. Microglia, the resident CNS macrophages, are implicated in ASD development and progression. Here we studied the impact of NLGN4 loss in a mouse model, focusing on microglia phenotype and function in both male and female mice. NLGN4 depletion caused lower microglia density, less ramified morphology, reduced response to injury and purinergic signaling specifically in the hippocampal CA3 region predominantly in male mice. Proteomic analysis revealed disrupted energy metabolism in male microglia and provided further evidence for sexual dimorphism in the ASD associated microglial phenotype. In addition, we observed impaired gamma oscillations in a sex-dependent manner. Lastly, estradiol application in male NLGN4(-/-) mice restored the altered microglial phenotype and function. Together, these results indicate that loss of NLGN4 affects not only neuronal network activity, but also changes the microglia state in a sex-dependent manner that could be targeted by estradiol treatment

Data Descriptor : A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment.Peer reviewe

Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer

To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L−1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4°C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature

Effects Of Some Weed Control Methods on Yield, Botanical Composition and Forage Quality in Subirrigated Grasslands of Cukurova

Araştırma Çukurova'nın taban meralarında ot verimi ve kalitesini düşüren, hayvanların merayı kullanımını sınırlandıran yabancı otlarla etkili mücadele yöntemlerinin belirlenmesi amacıyla 2006--2009 yılları arasında Adana ili Seyhan ilçesi Dervişler doğal merasında yürütülmüştür. Araştırma tesadüf blokları deneme desenine göre tekrarlamalı olarak yürütülmüştür. Deneme de biçme, gübreleme, 2.4--D, Picloram+2.4--D, Paraquat ve Glyphosate uygulamaları incelenmiştir. Üç yıIIık ortalamalara göre Picloram+2.4--D uygulamasının meranın kuru madde verimi ve sindirilebilir kuru madde verimini artırdığı, buğdaygillerin botanik kompozisyondaki oranını artırırken diğer familya bitkilerinin oranını azalttığını göstermiştir.Araştırma Çukurova’nın taban meralarında ot verimi ve kalitesini düşüren, hayvanların merayı kullanımını sınırlandıran yabancı otlarla etkili mücadele yöntemlerinin belirlenmesi amacıyla 2006—2009 yılları arasında Adana ili Seyhan ilçesi Dervişler doğal merasında yürütülmüştür. Araştırma tesadüf blokları deneme desenine göre tekrarlamalı olarak yürütülmüştür. Deneme de biçme, gübreleme, 2.4—D, Picloram+2.4—D, Paraquat ve Glyphosate uygulamaları incelenmiştir. Üç yıIIık ortalamalara göre Picloram+2.4—D uygulamasının meranın kuru madde verimi ve sindirilebilir kuru madde verimini artırdığı, buğdaygillerin botanik kompozisyondaki oranını artırırken diğer familya bitkilerinin oranını azalttığını göstermiştir