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Yayın Mülteci barınaklarının uydu görüntülerinden çoklu-sınıflı çizge-kesme bölütleme ve gölge bilgisi kullanılarak otomatik sezimi(IEEE, 2014-04-23) Kucur Ergünay, Şerife Seda; Kahraman, Fatih; Ateş, Hasan FehmiBu çalışmada, mülteci kamplarında bulunan yaşam alanlarının/barınakların (çadır, konteynır vb.) uydu ve hava görüntülerinden otomatik olarak sezimi ve sayımına yönelik bir yöntem tanıtılmaktadır. Mülteci kamplarındaki barınakların çok yüksek çözünürlüklü (VHR) görüntülerde dahi çok küçük boyuta sahip, belli bir alanda çok sık ve bazen karmaşık şekilde yerleştirilmiş ve arkaplan ile ayrıştırılması zor nesnelere denk geliyor olması otomatik barınak/çadır sezim ve sayımını zorlaştırmaktadır. Bahsedilen problemin çözümüne yönelik olarak çok sınıflı çizge-kesme (graph-cut) bölütlemesi ve gölge bilgisinin kullanıldığı özgün bir yöntem çalışma kapsamında önerilmektedir. Buna göre, ilk adımda çizge-kesme bölütleme yöntemi ve morfoloji işlemleri uygulanarak çadır sezimi yapılmıştır. Bu adımda sezilememiş çadırların bulunabilmesi için ikinci bir adımda çadırların gölge bilgisinden faydalanılmıştır. En son adımda gradyan-tabanlı eşikleme yöntemi ile yanlış tespitlerin elenmesi amaçlanmıştır. Önerilen yöntem, özellikle karmaşık yerleşim düzenine sahip mülteci kampları (çadırkent) üzerinde test edilmiştir. Yöntemin başarımı kesinlik (precision) ve geri getirme (recall) kriterlerine göre belirlenmiştir. Elde edilen ortalama kesinlik ve geri getirme başarımları sırasıyla %91.9 ve %90.0 olup problemin zorluğu göz önünde bulundurulduğunda umut vadedici bir sonuçtur.Yayın A critical question for bariatric surgery candidates: why do you think you need surgery and are you ready for change?(Springer, 2014-08-26) Deveci, Ezgi; Yücel, Başak; Sertel Berk, Hanife Özlem; Barbaros, Umut; Türker, Fulya[No abstract available]Yayın A global optimal control methodology and its application to a mobile robot model(Elsevier B.V., 2016) Dinçmen, ErkinA 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 Reviewing the effects of spatial features on price prediction for real estate market: Istanbul case(IEEE, 2022-09-16) Ecevit, Mert İlhan; Erdem, Zeki; Dağ, HasanIn the real estate market, spatial features play a crucial role in determining property appraisals and prices. When spatial features are considered, classification techniques have been rarely studied compared to regression, which is commonly used for price prediction. This study reviews spatial features' effects on predicting the house price ranges for real estate in Istanbul, Turkey, in the classification context. Spatial features are generated and extracted by geocoding the address information from the original data set. This geocoding and feature extraction is another challenge in this research. The experiments compare the performance of Decision Trees (DT), Random Forests (RF), and Logistic Regression (LR) classifier models on the data set with and without spatial features. The prediction models are evaluated based on classification metrics such as accuracy, precision, recall, and F1-Score. We additionally examine the ROC curve of each classifier. The test results show that the RF model outperforms the DT and LR models. It is observed that spatial features, when incorporated with non-spatial features, significantly improve the prediction performance of the models for the house price ranges. It is considered that the results can contribute to making decisions more accurately for the appraisal in the real estate industry.Yayın A New speech coding algorithm using zero cross and phoneme based SYMPES(IEEE, 2013-07-11) Şişman, Burak; Güz, Ümit; Gürkan, Hakan; Yarman, Bekir Sıddık BinboğaIn this work, a new low bit rate hybrid speech coding approach which combines the benefits of the SYMPES (Systematic Procedure for Predefined Envelope and Signature Sequences) and zero cross and phoneme based segmentation is proposed. In the new approach, the SYMPES structure is developed in the phoneme based fashion. In order to achieve lower bit rates, some drawbacks such as computational complexity, relatively high encoding times etc. of the SYMPES are also eliminated in the new version. Experimental results show that in almost same bit rates very promising speech quality is obtained compared to the other conventional methods such as CELP (Code Excited Linear Predictive) coding algorithm.Yayın A precision estimation method for volumetric changes(IEEE, 2019-06) Akça, Mehmet Devrim; Stylianidis, Efstratios; Gruen, Armin W.; Altan, Mehmet Orhan; Hofer, Martin; Smagas, Konstantinos; Sanchez Martin, Victor; Walli, Andreas; Jimeno, Elisa; Garcia, AlejandroEarth surface changes are often computed by comparing the sequences of digital elevation models (DEMs) so called the DEM of difference (DoD) method. We present an operational DEM generation, co-registration and DoD comparison software in which the surface changes are quantified in metric units of volume. A practical method, which is based on the law of error propagation, is developed to estimate the theoretical precisions of volumetric changes. The proposed pipeline can estimate the change of object volumes (in terms of loss and gain) together with their precision numbers. Change of the forest volume in a fire effected region in a test site is analyzed for the validation. The method can be used for various change detection applications related to forestry as well as other topics such as earthworks, geomorphology, mining, and urbanization.Yayın 2W wideband microwave PA design for 824-2170 MHz band using normalized gain function method(IEEE, 2013) Köprü, Ramazan; Kuntman, Hulusi Hakan; Yarman, Bekir Sıddık BinboğaIn this work, we present the design of a 2W linear wideband microwave PA (power amplifier) targeted to operate in 824-2170 MHz mobile frequency range covering GSM850, EGSM, DCS, PCS and WCDMA. The design is basically based on the NGF (Normalized Gain Function) method which is very recently introduced into the literature. NGF is defined as the ratio of T and |S-21|(2), i.e. T-NGF= T/|S-21|(2), shape of the gain function of the amplifier to be designed and the shape of the transistor forward gain function, respectively. Synthesis of input/output matching networks (IMN/OMN) of the amplifier requires target gain functions, which are mathematically generated in terms of TNGF. The particular transistor used in the design is FP31QF, a 2W HFET from TriQuint Semiconductor. Theoretical PA performance obtained in Matlab is shown to be in a very high agreement with the simulated performance in MWO (Microwave Office) of AWR Inc.Yayın Introducing professional skills during unit operations laboratory(American Society for Engineering Education, 2011-06-26) Rende, Sevinç; Rende, Deniz; Baysal, NihatUnit 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 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 Realities & constraints of coal from energy and environmental perspectives(University of Pittsburgh, 2010) Ekinci, Ekrem[No abstract available]
