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Yayın The DAG project and its management(Türk Astronomi Derneği, 2020-12-11) Zago, Lorenzo; Keskin, OnurThe DAG Project and managerial issues related to call for tenders, determination of technical specifications both for the telescope, the dome and the observatory building will be presented.Yayın The effects of atmospheric turbulence on astrophysical observations(Türk Astronomi Derneği, 2020-12-11) Keskin, OnurAtmospheric turbulence is caused by random variations in temperature and pressure that spatially and temporally alter the air’s index of refraction. As electro-magnetic radiation from distant astronomical objects propagates through the atmosphere, the waves of light are distorted by these fluctuations in the refractive index and the information stored in the wavefront is corrupted. For astronomers, this loss of information manifests as degradation in the angular resolution that can be achieved with a ground-based telescope.Yayın Adaptive optics for DAG telescope(Türk Astronomi Derneği, 2020-12-11) Keskin, Onur; Jolissaint, LaurentWhat we propose for DAG is therefore a natural guide star GLAO system, that can be turned into a highly efficient AO system. Thus the working principle and expected performance analysis will be shown. In this manner most DAG users will be able to make some use of the DAG AO. Later, it will be possible to upgrade the system by changing th algorithm and adding 1 or 2 additional DM, and even laser guide stars.Yayın The investigation of the effect of saturation flow on the average vehicle delay at signalized intersections(Izmir Democracy University, 2021-12-18) Çakıcı, Ziya; Aksoy, GökerSaturation flow (s) is one of the most important parameters used for determining of signal timings at signalized intersections. Therefore, this parameter directly affects the various intersection performance criteria such as queue length, average delay, the level of service and capacity. In this study, determination of the effect of saturation flow rate on the average vehicle delay is aimed. In the scope of the study, firstly, an optimization model which minimizes the average vehicle delay at the intersection is set. Then, a software which optimizes the signal timings at the intersection by using Differential Evolution Algorithm (DEA) is prepared in MATLAB environment. In the second stage, 15 traffic volume scenarios which have different total traffic volume from each other for a four-leg signalized intersection are created in order to test different traffic cases. Created scenarios are classified in 3 groups as Low Volume (LV), Moderate Volume (MV) and High Volume (HV). In the next stage, each scenario is analyzed considering 9 different saturation flow rates (s=1600, 1650, 1700, 1750, 1800, 1850, 1900, 1950, 2000 vehicle/hour/lane), separately. In case of implementing of these saturation flow rates, obtained signal optimum timings and average vehicle delay for each scenario are evaluated in details. In the last stage of the study, the average vehicle delays obtained by using s=1800 vehicle/hour/lane which is frequently encountered in many studies in the literature are compared with the average vehicle delays obtained by using other saturation flow rates, relatively. As a result of the comparisons, it is determined that the differences between average vehicle delays are quite low (between -0.9% and +1.2%) in case of Low Volume. In case of Moderate Volume, differences between -20.8% and +37.2% are seen. In case of High Volume, it can be said that the differences change between -41.4% and +116.3%. This situation clearly demonstrate that accurate and faultless measurement of saturation flow rate is quite important in terms of the performance of the intersection, especially in case of moderate and high volume.Yayın Observing with DAG: performance metrics of imaging and spectroscopy(Türk Astronomi Derneği, 2020-12-11) Jolissaint, Laurent; Zago, Lorenzo; Keskin, OnurDAG telescope will be designed as a telescope with adaptive optics and seeing limited modes of observation. Its primary mirror will be a thin meniscus, controlled in shape by an active optics system. This implies specific requirements for the mirrors manufacturing errors tolerancing, studied and defined in this document.Yayın Crypto currency applications in financial markets: factors affecting crypto currency prices(PressAcademia, 2020-07-30) Deniz, E. Asena; Teker, DilekPurpose- As the cryptocurrency market is beginning to attract investors, a new portfolio of cryptocurrencies has been published in the literature on macro-economic factors affecting these currencies. This research also aimed to identify the interaction between gold, brent oil, Bitcoin, Ethereum and Ripple. Methodology- The database includes the Daily prices of Bitcoin, Ethereum, Ripple, gold and brent oil prices between the period of 03.04.2018-31.12.2020 which consist of 500 daily data. Natural logaritm for each indicator is used. First, the stationarity of the series were analyzed with ADF (Augmented Dickey Fuller) unit root test. Lag lengths are determined. Interactions between the series were analyzed by the Johansen Cointegration test, Granger Causality test, Impulse- Response Function and Variance Decomposition method. Findings- The series are found out to be stationary at first difference. According to the cointegration test result, cointegration could not be found between our data. According to Granger causality analysis, only one-way relationship was found from bitcoin to gold. Impulse response graphs indicate that all variables respond in a reducing way to reducing shocks occurred in each indicator. Shocks have lost their effect on average in 2 days. Conclusion- The results indicate that the effect of gold and brent oil prices on bitcoin, ethereum, ripple daily prices do not have a strong effect. The results may be beneficial for investors to consider diversification for the portfolios.Yayın DAG odak düzlemi araçları - hedefler ve seçenekler(Türk Astronomi Derneği, 2020-12-11) Yerli, Sinan Kaan; Yeşilyaprak, Cahit; Keskin, Onur; Güver, TolgaDAG projesi çerçevesinde, teleskobun da tanımlanması ve optiğinin belirlenmesinden sonra Türk Astronomisinin gereksinim ve gelecek hedefleri de gözetilerek proje ekibi DAG teleskobunun iki Nasmyth odağına yerleştirilecek olası tayfölçer ve görüntüleme araçları için öngörülerde bulunmuş ve yeni bir proje teklifi vermiştir. Bu bildiride bu süreç tanıtılıp sunulan yeni proje tanıtılacaktır.Yayın Wealth management trends in the world(PressAcademia, 2020-07-30) Danon, Murat; Teker, SuatPurpose- The purpose of this research is to explore and identify the prevailing trends in the wealth management sector on a global scale. Methodology- As the main aim of the research is to identify the prevailing trends in the wealth management sector on a global scale, we have collected various statistical data sets regarding the various trends that are already established within the sector. Furthermore, we have also carried out interviews with two private bankers, one wealth management executive, and one wealth management client in order to get a substantial amount of insight on where the industry is headed. Findings- The wealth management sector has seen a rapid growth over the course of the last two decades but is being heavily impacted by the COVID-19 crisis. Conclusion- New trends look to impose new rules in the wealth management sector. COVID-19 and the existing economic troubles together may result in a significant slowdown in sectoral growth while a consolidation era for wealth management companies are commonly expected. Meanwhile, a dramatic change in most clients’ mindset and rapid adoption of more technology in the sector helping firms to reduce operational costs are foreseen.Yayın Turkish consumers’ behaviors in organic product market: an empirical application(PressAcademia, 2020-07-30) Ak, Anda Yarman; Teker, DilekPurpose- The purpose of this research is to determine whether gender, civil status, age, number of children in the family, education level of consumers, their cosmetic concerns, packaging of organic foods and reliability of certification process affect organic product purchase or not. It was also aimed to determine whether any modification ensuring the authenticity of organic products would convince the consumers to purchase / purchase more organic products. Methodology- To determine and test the hypothesis of the research a survey composed of 41 questions, divided into three main sections and a final section, is published on line during 26 days. The survey was replied by 556 respondents. Findings- The hypothesis which are tested and it is revealed that being female, an elder, having higher education or being a parent is not a reason to purchase organic products. On the other hand being married is a reason for purchase. Consumers do not consider cosmetic defects of organic products as a deterrent for not purchasing. Assured reliability on certification will increase organic product purchase, while packaging of organic products is important for consumers. Conclusion- The outputs of the research prove that the awareness on the benefits of organic products is increased among male and young consumers as well. People who have not a higher education degree also purchase organic products as the awareness is increases. Conscious consumers are paying attention to the packaging of organic products. The purchase rates and frequency shall increase when and if the reliability on certification is ensured and the increase on purchase can make organic product farming an economic resource for local farmers.Yayın Adaptation of the businesses not to fall behind in the new normal period(PressAcademia, 2020-07-30) Şerifsoy, Anıl; Teker, SuatPurpose - This paper aims to be an exploratory study that ascertains the impacts of COVID-19 on business life and ushers further research on the subject. Methodology - Internet-based research is conducted to collect the fundamental information on the impacts of COVID-19 on business life as secondary data. Findings- It is imminently possible that COVID-19 will be a milestone in business life due to changing many things; such as working conditions, working hours, working locations, brand strategy, innovation involvement and even changing the product itself. Conclusion- This article is intended to be one of the first steps of a guide for the business owners to take appropriate action and adapt to the new normal in the future not to fall behind in the harsh conditions of the demanding markets.
