Arama Sonuçları

Listeleniyor 1 - 10 / 126
  • Yayın
    A global optimal control methodology and its application to a mobile robot model
    (Elsevier B.V., 2016) Dinçmen, Erkin
    A global optimal control algorithm is developed and applied to an omni-directional mobile robot model. The aim is to search and find the most intense signal source among other signal sources in the operation region of the robot. In other words, the control problem is to find the global extremum point when there are local extremas. The locations of the signal sources are unknown and it is assumed that the signal magnitudes are maximum at the sources and their magnitudes are decreasing away from the sources. The distribution characteristics of the signals are unknown, i.e. the gradients of the signal distribution functions are unknown. The control algorithm also doesn't need any position measurement of the robot itself. Only the signal magnitude should be measured via a sensor mounted on the robot. The simulation study shows the performance of the controller.
  • Yayın
    Introducing professional skills during unit operations laboratory
    (American Society for Engineering Education, 2011-06-26) Rende, Sevinç; Rende, Deniz; Baysal, Nihat
    Unit operations laboratory (UOL) course is considered to be a crucial and integral part of the chemical engineering education. The primary objective of the course is to enable students to combine theory and practice. Problems in industry however entail more than finding technical solutions. Indeed professional life requires other skills such as an ability to propose ideas, develop practical solutions, participate in teamwork, meet deadlines, establish communication between technical support and suppliers, oversee financial issues, and finally reporting and presentation skills. This study describes how in three consecutive courses, we preserve academic rigor of the UOL course while incorporating components such as experimental design, project development and teamwork, which aim to meet the needs of professional careers. We follow up the course outcomes with a survey targeting the graduates of the program. The results show that graduates employed in industry frequently rely on these skills during job interviews, research and product development, whereas those who pursue advanced degrees in academia use these skills predominantly for their research, highlighting the need for adaptive approach for different graduate trajectories in designing the course. For both groups of graduates, the skills introduced during the UOL courses are reported to be valuable in their daily life, emphasizing life-long learning.
  • Yayın
    Stochastic surface mesh reconstruction
    (International Society for Photogrammetry and Remote Sensing, 2018-05-30) Özendi, Mustafa; Akça, Mehmet Devrim; Topan, Hüseyin
    A generic and practical methodology is presented for 3D surface mesh reconstruction from the terrestrial laser scanner (TLS) derived point clouds. It has two main steps. The first step deals with developing an anisotropic point error model, which is capable of computing the theoretical precisions of 3D coordinates of each individual point in the point cloud. The magnitude and direction of the errors are represented in the form of error ellipsoids. The following second step is focused on the stochastic surface mesh reconstruction. It exploits the previously determined error ellipsoids by computing a point-wise quality measure, which takes into account the semi-diagonal axis length of the error ellipsoid. The points only with the least errors are used in the surface triangulation. The remaining ones are automatically discarded.
  • Yayın
    Laboratory flume experiment with a coded structured light system
    (International Society for Photogrammetry and Remote Sensing, 2012) Akça, Mehmet Devrim; Seybold, Hansjorg
    The topography of inland deltas is influenced chiefly by the water-sediment balance in distributary channels and local evaporation and seepage rates. In a previous study, a reduced complexity model has been applied to simulate the process of inland delta formation. Results have been compared with the Okavango Delta, Botswana and with a laboratory experiment. Both in the macro scale and the micro scale cases, high quality digital elevation models (DEM) are essential. This work elaborates the laboratory experiment where an artificial inland delta is generated on laboratory scale and its topography is measured using a Breuckmann 3D scanner. The space-time evolution of the inland delta is monitored in the consecutive DEM layers. Regarding the 1.0m x 1.0m x 0.3m size of the working area, better than 100 micron precision is achieved which gives a relative precision of 1/10 000. The entire 3D modelling workflow is presented in terms of scanning, co-registration, surface generation, editing, and visualization steps. The co-registered high resolution topographic data allows us to analyse the stratigraphy patterns of the experiment and gain quantitative insight into the spatio-temporal evolution of the delta formation process.
  • Yayın
    STEAM approach in architectural education
    (EDP Sciences, 2019-06-22) Süyük Makaklı, Elif
    Architecture practice is reshaped by new technological developments such as virtual reality, augmented reality, 3D printing, computational design, robotics, etc. Future architects are expected to deliver spatial solutions, to understand changing living conditions and to discover the different future by responsing technological improvements. In architecture schools, students should explore and investigate design practice with different production methods, systems and materials by using various technologies in collaborations with interdisciplinary partners and industry. The study aims to understand the STEAM concept which is considered as a promising education approach and formulated; science, technology, engineering, math and then adds an 'A' for arts which represents the creative thinking and design approach. The STEAM concept and its place in the architectural education are discussed. The discipline of architecture is an intersection of technology, art and science. The architecture schools' curriculum reflects the interdisciplinary STEAM nature throughout the history. Virtual Reality (VR) is created through interdisciplinary technology and has the potential to prepare the students to future, to develop analytical and abstraction abilities.
  • Yayın
    Women's empowerment and welfare traformation in the context of microcredit in Turkey
    (Pressacademia, 2015-06-04) Soykut Sarıca, Yeşim Pınar; Çağlı Kaynak, Elif
    Gender inequalities are of the main problems in almost every society. Like all other parts of the system, economic and business environment haven't attempted sufficiently in struggling with this issue. When these inequalities combined with development problems the growth of poverty among women and their exclusion from society multiplies. Although there is so much struggle for constructing equal society women are still considered as ignorant part of the society and hence, vulnerable beings, who have to be protected and taken care of. In this sense women have not much chance for being "independent individual" both in social and economic terms. However these constraints upon women's vulnerability and inability are tried to be changed by Microfinance system to move from the perspective of women's empowerment. In this paper, we try to analyze whether the performance of practices by the non-governmental organizations ability to achieve objective to improve the living conditions and interest of the women in the society or not by comparing to micro credit organizations in Turkey. We also try to answer whether women's participation in employment contributes to well-being their lives and contributes their role in working life.
  • Yayın
    Calix[4]amine Langmuir-Blodgett thin film sensing properties against volatile organic compounds
    (IOP Publishing LTD, 2019) Şen, Sibel; Çapan, Rifat; Özbek, Zikriye; Özel, Mehmet Emin; Stanciu, Gheorghe A.; Davis, Frank
    Thin films of CBAMINE were deposited at air-water interface by the method of Langmuir-Blodgett (LB) technique onto a suitable substrate. Atomic force microscopy technique was used to characterize its thin film properties. The results indicate that a uniform LB film monolayer from the water surface to a glass or quartz crystal substrates deposited with a transfer ratio of over 96 %. Gas sensing properties and thickness of the LB thin films of CBAMINE were investigated using Surface plasmon resonance (SPR) technique. Its vapour sensing properties were investigated for different volatile organic compounds. Reversible changes in the optical behaviour were observed and thin films of this material are highly selective for chloroform vapour with fast response and recovery times.
  • Yayın
    Real-time frame buffer implementation based on external memory using FPGA
    (Elsevier B.V., 2018) Davutoğlu, Doğancan; Yıldız, Nerhun; Ayten, Umut Engin; Tavşanoğlu, Ahmet Vedat
    In this paper, design of a real-time video frame buffer with an external memory interface is proposed. In addition, simulation and implementation processes of the design is described. The mentioned system is able to buffer video signals up to 1920×1080 full-HD resolution at 60 Hz frame rate. The memory interface is designed based on an external SDRAM memory and supports burst read/write operations. Input video resolution, video buffer size on memory and burst size of the memory interface are user defined and can be configured.
  • Yayın
    Photogrammetric deformation monitoring of the second Bosphorus Bridge in Istanbul
    (International Society for Photogrammetry and Remote Sensing, 2014) Avşar, Özgür; Akça, Mehmet Devrim; Altan, Mehmet Orhan
    Improving the efficiency of bridge inspection and minimizing the impact of dynamic load on the long term deterioration of the bridge structure reduces maintenance and upkeep costs whilst also improving bridge longevity and safety. This paper presents the results of an on-going project whose ultimate goal is the real-time photogrammetric monitoring the structural deformations of the second Bosphorus Bridge of Istanbul.
  • Yayın
    Numerical investigation of the effect of radial lip seal geometry on sealing performance
    (IOP Publishing Ltd, 2018) Tok, Görkem; Parlar, Zeynep; Temiz, Vedat
    Sealing elements are often needed in industry and especially in machine design. With the change and development of machine technology from day to day, sealing elements show continuous development and change in parallel with these developments. Many factors influence the performance of the sealing elements such as shaft surface roughness, radial force, lip geometry etc. In addition, the radial lip seals must have a certain pre-load and interference in order to provide a good sealing. This also affects the friction torque. Researchers are developing new seal designs to reduce friction losses in mechanical systems. In the presented study, the effect of the lip seal geometry on sealing performance will be examined numerically. The numerical model created for this purpose will be verified with experimental data firstly. In the numerical model, shaft and seal will be modeled as hyper-elastic in 2D and 3D. NBR (Nitrile Butadiene Rubber) as seal material will be analyzed for the rotating shaft state at constant speed by applying a uniform radial force.