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Yayın Integrated opto-dynamic modeling of the 4-m DAG telescope image quality performance(SPIE-Int Soc Optical Engineering, 2016) Zago, Lorenzo; Guex, Benjamin; Yeşilyaprak, Cahit; Yerli, Sinan Kaan; Keskin, OnurThe Turkish DAG 4-m telescope is currently through the final design stage. It is to be located on a 3170 m mountain top in Eastern Anatolia. The telescope will be a state-of-The art device, alt-Az mount with active primary and adjustable secondary and tertiary mirrors. Its optics design is specially aimed at being compatible with advance adaptive optics instrumentation. The ultimate performance of such a telescope results of multiple concurrent effects from many different components and active functions of the complex system. The paper presents a comprehensive integrated (end-To-end) model of the telescope, comprising in one computational sequence all structural, electrodynamics and oactive optics performance that produce the image quality at the focal plane. The model is entirely programmed in Matlab/Simulink and comprises a finite element model of structure and mirrors, dynamics modal reduction, deformation analyses of structural and optical elements, active optics feedback control in the Zernike modal space.Yayın Tractable supply chain production planning, modeling nonlinear lead time and quality of service constraints(Elsevier Ltd, 2007) Anlı, Osman Murat; Caramanis, Michael C.; Paschalidis, Ioannis Ch.This paper addresses the task of coordinated planning of a supply chain (SC). Work in process (WIP) in each facility participating in the SC, finished goods inventory, and backlogged demand costs are minimized over the planning horizon. In addition to the usual modeling of linear material flow balance equations, variable lead time (LT) requirements, resulting from the increasing incremental WIP as a facility's utilization increases, are also modeled. In recognition of the emerging significance of quality of service (QoS), that is control of stockout probability to meet demand on time, maximum stockout probability constraints are also modeled explicitly. Lead time and QoS modeling require incorporation of nonlinear constraints in the production planning optimization process. The quantification of these nonlinear constraints must capture statistics of the stochastic behaviour of production facilities revealed during a time scale for shorter than the customary weekly time scale of the planning process. The apparent computational complexity of planning production against variable LT and QoS constraints has long resulted in MRP-based scheduling practices that ignore the LT and QoS constraints has long resulted in MRP-based scheduling practices that ignore the LT and QoS impact to the plan's detriment. The computational complexity challenge was overcome by proposing and adopting a time-scale decomposition approach to production planning where short-time-scale stochastic dynamics are modeled in multiple facility-specific subproblems that receive tentative targets from a deterministic master problem and return statistics to it. A converging and scalable iterative methodology is implemented, providing evidence that significantly lower cost production plans are achievable in a computationally tractable manner.Yayın ICamp - The educational web for higher education(Springer Verlag, 2006) Kieslinger, Barbara; Wild, Fridolin; Arsun, Onur İhsaniCamp is an EC-funded research project in the area of Technology Enhanced Learning (TEL) that aims to support collaboration and social networking across systems, countries and disciplines in higher education. The concept of an iCamp Space will build on existing interfaces and integrate shared community features. Interoperability amongst different open source learning systems and tools is the key to successful sustainability of iCamp. The content for this collaboration within social communities is provided via distributed networked repositories including, for example, content brokerage platforms, online libraries, and learning object databases. The innovative pedagogical model of iCamp is based on social constructivist learning theories. iCamp creates an environment for a new way of social networking in higher education that puts more emphasis on self-organised, self-directed learning, social networking and cross-cultural collaboration.Yayın Innovative project management: A case study in electronics industry(Işık Üniversitesi, 2019-04-15) Sadıç, Alican; Eyüpgiller, Sait Saygın; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Yöneticiler İçin İşletme Yönetimi Yüksek Lisans ProgramıManagement of economic units is as old as the history of civilizations; however, the formation of the project management methodology and the determination of its rules have been established rather recently. The most important historical examples of project management in the construction and architecture area happened especially in the period between the 18th and 19th centuries. The most beautiful and oldest historical reference project may be the construction of Egyptian Pyramids. Nowadays, project management has also become a distinctive way to manage business activities. Most of accomplished companies in all industries are using project management techniques, and the companies using project management for the operations. On the other hand, the importance of innovation in our life has increased in daily life with the increasing global competitive environment. Innovation has also become a distinctive part of management theory. The increase in innovation performance of countries has a key role on business economic ans social development, prosperity, and growth in our time. For this reason, project-based firms have started to apply innovationtechniques more than ever. These firms started to become a more vital and important organizational context, as examples many current managerial challenges. Innovative Project Management techniques should use owing to the effect of technology and its influence on organizational processes. It is an essential aspect of many growth strategy. Society gains much greater benefits from the same sources with the value added of the innovation. Therefore, innovation is not only economic and business system but also it is a social system. Innovation is located within a dynamic environment which is especially affected by the following elements; technology firms, market uncertainties, rapid change, shortened product life cycle, and globalization. Therefore; it is inevitable for organizations to be innovative for sustainability, for competition, for being able to grow and leading their market. This thesis, with a case study and research about Innovative Project Management examines the functioning of an innovative based company about UPS - (Uninterrupted Power Supply) project in electronics industry. The study also strives to discover the added value to the UPS project through Innovative Project Management.Yayın Strategic alignment and project management offices: case studies from successful implementations in Turkey(IEEE, 2013-03-18) Karayaz, Gamze; Güngör, ÖzgeDue to an increased need for learning modern project management methodologies, companies have been forced to improve their knowledge of Project Management Offices (PMO). Global business environment resulted with increased importance of project management methodologies, aligned with competitive strategies. Today, many organizations have recognized the importance of implementing PMO's for effective project control and better stakeholder (executives) support for projects. PMOs also undertake strategic roles such as incorporating higher management support to achieve strategic goals, integrating business strategies into project management efforts, and prioritization of projects. This paper examines PMOs in the process of strategic alignment. Moreover, the contribution of PMOs to achieve strategic goals is explored. Our initial findings are promising represented in a framework, and demonstrated by a case study application review using IT and telecommunication companies selected from Turkey. The research offers future directions and implications of a well-established successful PMO system.Yayın Crisis project management and the effect of national culture under crisis: A study from Turkey(Pressacademia, 2016-05-26) Karayaz, Gamze; Kaptan, Aşkın KaanCrisis management is a critical function in organizations, specifically developing and emerging countries dealing with crisis in a minor and major scale frequently. Crisis in projects should be handled immediately and professionally in where the projects threat the reputation of a company. In traditional organizations, most common organizational behavior under crisis seems to take the risk with no supported mechanism. Project management based organizations practice risk management under project management methodologies, surprisingly we cannot find many companies are prepared for crisis. This behavior may associate with national culture, especially Hofstede's extensive work on national cultures. Therefore, this paper investigates cultural characteristics of Turkish business culture under crisis, and identifies the relationship with the natural culture dimensions and crisis project management. Two-stages survey questionnaires are employed and data analyzed using different statistical analysis. Our results indicate that power distance, uncertainty avoidance, and long-term orientations are the national cultural dimensions observed significantly under crisis situations. Further investigation and recommendations are discussed.Yayın DAG 4m telescope: assembly, integration and testing(SPIE-Int Soc Optical Engineering, 2018-07-06) Pirnay, Olivier; Lousberg, Grégory P.; Gabriel, Eric; Marchiori, Gianpietro; Busatta, Andrea; Yeşilyaprak, Cahit; Keskin, OnurAMOS with EIE as a main subcontractor, was awarded a contract in November 2014 for the design, manufacturing and installation of a 4m-class telescope for the Turkish Eastern Anatolia Observatory (DAG) situated at 3170 m above the sea level in Palandöken mountains. The telescope is based on a Ritchey-Chretien configuration with two folded Nasmyth focal planes and a focal length of 56m. Diffraction-limited performances will be reached thanks to the combination of the active optics system and the adaptive optics system that will be implemented on one of the Nasmyth ports. The active optics system aims at controlling the shape of the primary mirror by means of 66 axial force actuators and positioning actively the secondary and tertiary mirrors by means of hexapods. More than 30 years of experience in testing instruments and telescopes, including optical testing, alignment, metrology, mechanical static and dynamic measurements, system identification, etc. allow to implement an adequate verification strategy combining component level verifications with factory and site test in the most efficient and reliable manner. As a main contractor, AMOS is in charge of the overall project management, the system engineering, the optical design and the active optics development. As a main sub-contractor and partner of AMOS, EIE is in charge of the development of the mount. The factory test therefore takes place in EIE premises. In this paper is shortly presented the overall design of the telescope with a review of the specification, the optical design and a description of the major sub-systems, including the optics. The assembly, integration et test plan is outlined. The assembly sequence and the tests of the active optics and the mount are discussed. Finally, the site integration and tests are explained. The process to assess the image quality of the telescope and the verification instrument developed for this purpose by AMOS are presented.Yayın Observatory building design: A case study of DAG with infrastructure and facilities(SPIE, 2016-08-19) Şahmalı, Ali Erkan; Yeşilyaprak, Cahit; Yerli, Sinan Kaan; Keskin, OnurEastern Anatolian Observatory (DAG), will be built in one of the well-known mountain ridges of Erzurum, Turkey, at latitude of 39°46'50, longitude of 41°13'35 and an altitude of 3.151 meters. As well as erecting the largest telescope of Turkey, the DAG project aims to establish an observatory complex both small in size and functional enough to give service to all astronomy community. In this paper, the challenge is explained in details: geological and geographical limitations, environmental and meteorological constraints, engineering and structural considerations, energy efficiency and sustainability.Yayın DAG 4m telescope: optics completion, on-site integration and test(SPIE, 2022) Pirnay, Olivier; Albart, Pierre; Bastin, Christian; De Ville, Jonathan; Gabriel, Eric; Leseur, Thibault; Lousberg, Grégory P.; Méant, Laurence; Orban, Sabrina; Tortolani, Jean-Marc; Amalfi, Manfredi; Marchiori, Gianpietro; Rampini, Francesco; Busatta, Andrea; Yeşilyaprak, Cahit; Keskin, OnurAMOS with EIE as main subcontractor has recently completed the erection of the 4 m telescope located at the Turkish Eastern Anatolia Observatory (DAG) set up by the Ataturk University Astrophysics Research and Application Centre (ATASAM) of Erzurum. The telescope design is based on a Ritchey-Chrétien configuration with two folded Nasmyth focal planes and a focal length of 56m. The optical train is composed of three mirrors: the primary mirror (M1) with an optical aperture of 4m, a convex secondary mirror (M2), and a large flat folding mirror (M3). Diffraction-limited performances in optical and near infrared spectral bands will be achieved thanks to the combination of active and adaptive optics systems. The active optics system is controlling the shape of the primary mirror by means of 66 axial force actuators and position actively the secondary and tertiary mirrors by means of hexapods. The adaptive optics system will be implemented at one of the two Nasmyth ports. As main contractor, AMOS is in charge of the overall project management, the system engineering, the optical design and the active optics development. As main sub-contractor and partner of AMOS, EIE is in charge of the development of the mount. Following the factory acceptance in Europe, the telescope was dismounted and delivered in early 2021. The activities onsite were carried out according to the assembly, integration and verification plan (AIV plan). In the meantime, the fabrication of the 4 m primary mirror was completed, and the full set of mirrors was forwarded on-site before the end of the year 2021. In this paper is presented a brief description of the design and performances of the telescope followed by the project progress status at the time the optics are being integrated in the telescope for the first time. This includes the review of the mirrors as-built quality and the excepted performances of the telescope mount after alignment and tuning. The path forward final acceptance is explained with the presentation of the optical alignment method and the test carried-out on-sky.Yayın Coordination in building an observatory: A case study of Eastern Anatolian Observatory (DAG)(SPIE-Int Soc Optical Engineering, 2018) Şahmalı, Ali Erkan; Yeşilyaprak, Cahit; Keskin, OnurEastern Anatolian Observatory (DAG) is designed to build on one of the summits of Palandoken Mountains in Erzurum, Turkey, at an altitude of 3,151 meters. The building is under construction since 2015 and expected to be completed in 2020. The building is designed as an integrated building, having operational departments, services, mechanical and electrical infrastructure for observations as well as cleaning and coating units, adjacent to the main observatory building. As one might expect this integration creates serious coordination problems between architect, engineers, telescope, enclosure, and cleaning & coating unit manufacturers. The construction progress of the investment is almost 20%. There are quite an amount of "lessons learned" in this period, and need to be developed by the parties, for their existing and future works. The building has so many challenges such as geological and geographical limitations, environmental and meteorological constraints, engineering and structural considerations, energy efficiency and sustainability, materials used and their performances at these limitations.
