2015
Turemen, G; Yasatekin, B; Ogur, S; Yildiz, V; Mete, O; Oz, S; Ozbey, A; Yildiz, H; ..., Current status of the SANAEM RFQ accelerator beamline Journal Article arXiv preprint arXiv:1504., 7677 , 2015. @article{pop00010b, title = {Current status of the SANAEM RFQ accelerator beamline}, author = {G Turemen and B Yasatekin and S Ogur and V Yildiz and O Mete and S Oz and A Ozbey and H Yildiz and ...}, year = {2015}, date = {2015-01-01}, journal = {arXiv preprint arXiv:1504.}, volume = {7677}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Yaman, Fatih; Yakhno, Valery G; Özdemir, Caner; Yu, Tzu Yang; Potthast, Roland Recent theory and applications on inverse problems 2014 Miscellaneous 2015, ISSN: 15635147. @misc{Yaman2015a, title = {Recent theory and applications on inverse problems 2014}, author = {Fatih Yaman and Valery G Yakhno and Caner Özdemir and Tzu Yang Yu and Roland Potthast}, doi = {10.1155/2015/403729}, issn = {15635147}, year = {2015}, date = {2015-01-01}, booktitle = {Mathematical Problems in Engineering}, abstract = {Fine particulate matter emitted during meat cooking is known to contribute a significant fraction of the total fine aerosol concentration in urban areas. In the present study, polar organiccompoundsinmeatsmokefine particulate matter are converted to their trimethylsilyl derivatives and analyzed by gas chromatography/mass spectrometry. Silylation enables the detection of monoglycerides in the meat smoke extracts and enhances the detection of cholesterol. These compounds are detected in atmospheric fine particle samples collected in Bakersfield, CA, with relative abundances that show substantial agreement betweenthemeatsmokesource samplesandthe atmosphere. The data suggest that the saturated monoglycerides, as well as cholesterol, may be suitable for use as tracers for the atmospheric particles generated by meat cooking operations.}, keywords = {}, pubstate = {published}, tppubtype = {misc} } Fine particulate matter emitted during meat cooking is known to contribute a significant fraction of the total fine aerosol concentration in urban areas. In the present study, polar organiccompoundsinmeatsmokefine particulate matter are converted to their trimethylsilyl derivatives and analyzed by gas chromatography/mass spectrometry. Silylation enables the detection of monoglycerides in the meat smoke extracts and enhances the detection of cholesterol. These compounds are detected in atmospheric fine particle samples collected in Bakersfield, CA, with relative abundances that show substantial agreement betweenthemeatsmokesource samplesandthe atmosphere. The data suggest that the saturated monoglycerides, as well as cholesterol, may be suitable for use as tracers for the atmospheric particles generated by meat cooking operations. |
Akhmedov, M; Çatay, B; Apaydın, MS Automating unambiguous NOE data usage in NVR for NMR protein structure-based assignments Journal Article Journal of Bioinformatics and Computational Biology, 13 (6), pp. 1550020–1550020, 2015. @article{pop00006m, title = {Automating unambiguous NOE data usage in NVR for NMR protein structure-based assignments}, author = {M Akhmedov and B Çatay and MS Apaydın}, year = {2015}, date = {2015-01-01}, journal = {Journal of Bioinformatics and Computational Biology}, volume = {13}, number = {6}, pages = {1550020--1550020}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Aycan, Esra; Özbek, Berna; Ruyet, Didier Le Improved successive stream selection with quantized channel in heterogeneous networks Inproceedings Proceedings of the International Symposium on Wireless Communication Systems, 2015, ISSN: 21540225. @inproceedings{Aycan2015, title = {Improved successive stream selection with quantized channel in heterogeneous networks}, author = {Esra Aycan and Berna Özbek and Didier Le Ruyet}, doi = {10.1109/ISWCS.2015.7454418}, issn = {21540225}, year = {2015}, date = {2015-01-01}, booktitle = {Proceedings of the International Symposium on Wireless Communication Systems}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Baştürk, Ilhan; Özbek, Berna Resource allocation for user-relay assisted MISO-OFDMA networks Inproceedings Proceedings of the International Symposium on Wireless Communication Systems, 2015, ISSN: 21540225. @inproceedings{Basturk2015, title = {Resource allocation for user-relay assisted MISO-OFDMA networks}, author = {Ilhan Baştürk and Berna Özbek}, doi = {10.1109/ISWCS.2015.7454312}, issn = {21540225}, year = {2015}, date = {2015-01-01}, booktitle = {Proceedings of the International Symposium on Wireless Communication Systems}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Beyazit, EA; Ozbek, B; Ruyet, Le D Interference alignment with improved stream selection in heterogeneous networks Journal Article Signal Processing and Communications Applications Conference (SIU), 2015 …, 2015. @article{pop00044b, title = {Interference alignment with improved stream selection in heterogeneous networks}, author = {EA Beyazit and B Ozbek and Le D Ruyet}, year = {2015}, date = {2015-01-01}, journal = {Signal Processing and Communications Applications Conference (SIU), 2015 …}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Ide, C; Yüksel, K Uzun Periyotlu Fiber Izgara Sensörün Kırılma İndisi Hassasiyetinin Modellenmesi Journal Article FOTONİK 2015, 17. Ulusal Optik, Elektro-Optik ve Fotonik Çalıştayı, pp. 15–16, 2015. @article{pop00039b, title = {Uzun Periyotlu Fiber Izgara Sensörün Kırılma İndisi Hassasiyetinin Modellenmesi}, author = {C Ide and K Yüksel}, year = {2015}, date = {2015-01-01}, journal = {FOTONİK 2015, 17. Ulusal Optik, Elektro-Optik ve Fotonik Çalıştayı}, pages = {15--16}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Durbas, Sukru; Ozbek, Berna Energy-efficient resource allocation for multiuser OFDM wireless networks Inproceedings 2015. @inproceedings{Durbas2015, title = {Energy-efficient resource allocation for multiuser OFDM wireless networks}, author = {Sukru Durbas and Berna Ozbek}, doi = {10.1109/siu.2015.7129998}, year = {2015}, date = {2015-01-01}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Karakuş, O; Kuruoğlu, EE; Altinkaya, MA Estimation of the nonlinearity degree for polynomial autoregressive processes with RJMCMC Journal Article 2015 23rd European Signal Processing Conference (EUSIPCO), pp. 953–957, 2015. @article{pop00004cb, title = {Estimation of the nonlinearity degree for polynomial autoregressive processes with RJMCMC}, author = {O Karakuş and EE Kuruoğlu and MA Altinkaya}, year = {2015}, date = {2015-01-01}, journal = {2015 23rd European Signal Processing Conference (EUSIPCO)}, pages = {953--957}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Karakus, Oktay; Kuruoglu, Ercan E; Altinkaya, Mustafa A Long term wind speed prediction with polynomial autoregressive model Inproceedings 2015. @inproceedings{Karakus2015, title = {Long term wind speed prediction with polynomial autoregressive model}, author = {Oktay Karakus and Ercan E Kuruoglu and Mustafa A Altinkaya}, doi = {10.1109/siu.2015.7129907}, year = {2015}, date = {2015-01-01}, abstract = {textcopyright 2015 IEEE. Wind energy is one of the preferred energy generation methods because wind is an important renewable energy source. Prediction of wind speed in a time period, is important due to the one-to-one relationship between wind speed and wind power. Due to the nonlinear character of the wind speed data, nonlinear methods are known to produce better results compared to linear time series methods like Autoregressive (AR), Autoregressive Moving Average (ARMA) in predicting in a period longer than 12 hours. A method is proposed to apply a 48-hour ahead wind speed prediction by using the past wind speed measurements of the Çeşme Peninsula. We proposed to model wind speed data with a Polynomial AR (PAR) model. Coefficients of the models are estimated via linear Least Squares (LS) method and up to 48 hours ahead wind speed prediction is calculated for different models. In conclusion, a better performance is observed for higher than 12-hour ahead wind speed predictions of wind speed data which is modelled with PAR model, than AR and ARMA models.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } textcopyright 2015 IEEE. Wind energy is one of the preferred energy generation methods because wind is an important renewable energy source. Prediction of wind speed in a time period, is important due to the one-to-one relationship between wind speed and wind power. Due to the nonlinear character of the wind speed data, nonlinear methods are known to produce better results compared to linear time series methods like Autoregressive (AR), Autoregressive Moving Average (ARMA) in predicting in a period longer than 12 hours. A method is proposed to apply a 48-hour ahead wind speed prediction by using the past wind speed measurements of the Çeşme Peninsula. We proposed to model wind speed data with a Polynomial AR (PAR) model. Coefficients of the models are estimated via linear Least Squares (LS) method and up to 48 hours ahead wind speed prediction is calculated for different models. In conclusion, a better performance is observed for higher than 12-hour ahead wind speed predictions of wind speed data which is modelled with PAR model, than AR and ARMA models. |
Bozkurt, Bariş; Karacali, Bilge A computational analysis of Turkish makam music based on a probabilistic characterization of segmented phrases Journal Article Journal of Mathematics and Music, 2015, ISSN: 17459745. @article{Bozkurt2015, title = {A computational analysis of Turkish makam music based on a probabilistic characterization of segmented phrases}, author = {Bariş Bozkurt and Bilge Karacali}, doi = {10.1080/17459737.2014.927012}, issn = {17459745}, year = {2015}, date = {2015-01-01}, journal = {Journal of Mathematics and Music}, abstract = {textcopyright 2014 Taylor & Francis. This study targets automatic analysis of Turkish makam music pieces on the phrase level. While makam is most simply defined as an organization of melodic phrases, there has been very little effort to computationally study melodic structure in makam music pieces. In this work, we propose an automatic analysis algorithm that takes as input symbolic data in the form of machine-readable scores that are segmented into phrases. Using a measure of makam membership for phrases, our method outputs for each phrase the most likely makam the phrase comes from. The proposed makam membership definition is based on Bayesian classification and the algorithm is specifically designed to process the data with overlapping classes. The proposed analysis system is trained and tested on a large data set of phrases obtained by transferring phrase boundaries manually written by experts of makam music on printed scores, to machine-readable data. For the task of classifying all phrases, or only the beginning phrases to come from the main makam of the piece, the corresponding F-measures are.52 and.60 respectively.}, keywords = {}, pubstate = {published}, tppubtype = {article} } textcopyright 2014 Taylor & Francis. This study targets automatic analysis of Turkish makam music pieces on the phrase level. While makam is most simply defined as an organization of melodic phrases, there has been very little effort to computationally study melodic structure in makam music pieces. In this work, we propose an automatic analysis algorithm that takes as input symbolic data in the form of machine-readable scores that are segmented into phrases. Using a measure of makam membership for phrases, our method outputs for each phrase the most likely makam the phrase comes from. The proposed makam membership definition is based on Bayesian classification and the algorithm is specifically designed to process the data with overlapping classes. The proposed analysis system is trained and tested on a large data set of phrases obtained by transferring phrase boundaries manually written by experts of makam music on printed scores, to machine-readable data. For the task of classifying all phrases, or only the beginning phrases to come from the main makam of the piece, the corresponding F-measures are.52 and.60 respectively. |
Karakilinc, OO; Dinleyici, MS Design of dual‐mode dual‐band photonic crystal bandpass filters for terahertz communication applications Journal Article Microwave and Optical Technology Letters, 57 (8), pp. 1806–1810, 2015. @article{pop00008e, title = {Design of dual‐mode dual‐band photonic crystal bandpass filters for terahertz communication applications}, author = {OO Karakilinc and MS Dinleyici}, year = {2015}, date = {2015-01-01}, journal = {Microwave and Optical Technology Letters}, volume = {57}, number = {8}, pages = {1806--1810}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Ahsan, Syed Saad; Gumus, Abdurrahman; Jain, Aadhar; Angenent, Largus T; Erickson, David Integrated hollow fiber membranes for gas delivery into optical waveguide based photobioreactors Journal Article Bioresource Technology, 2015, ISSN: 18732976. @article{Ahsan2015, title = {Integrated hollow fiber membranes for gas delivery into optical waveguide based photobioreactors}, author = {Syed Saad Ahsan and Abdurrahman Gumus and Aadhar Jain and Largus T Angenent and David Erickson}, doi = {10.1016/j.biortech.2015.06.028}, issn = {18732976}, year = {2015}, date = {2015-01-01}, journal = {Bioresource Technology}, abstract = {Compact algal reactors are presented with: (1) closely stacked layers of waveguides to decrease light-path to enable larger optimal light-zones; (2) waveguides containing scatterers to uniformly distribute light; and (3) hollow fiber membranes to reduce energy required for gas transfer. The reactors are optimized by characterizing the aeration of different gases through hollow fiber membranes and characterizing light intensities at different culture densities. Close to 65% improvement in plateau peak productivities was achieved under low light-intensity growth experiments while maintaining 90% average/peak productivity output during 7-h light cycles. With associated mixing costs of ~1. mW/L, several magnitudes smaller than closed photobioreactors, a twofold increase is realized in growth ramp rates with carbonated gas streams under high light intensities, and close to 20% output improvement across light intensities in reactors loaded with high density cultures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Compact algal reactors are presented with: (1) closely stacked layers of waveguides to decrease light-path to enable larger optimal light-zones; (2) waveguides containing scatterers to uniformly distribute light; and (3) hollow fiber membranes to reduce energy required for gas transfer. The reactors are optimized by characterizing the aeration of different gases through hollow fiber membranes and characterizing light intensities at different culture densities. Close to 65% improvement in plateau peak productivities was achieved under low light-intensity growth experiments while maintaining 90% average/peak productivity output during 7-h light cycles. With associated mixing costs of ~1. mW/L, several magnitudes smaller than closed photobioreactors, a twofold increase is realized in growth ramp rates with carbonated gas streams under high light intensities, and close to 20% output improvement across light intensities in reactors loaded with high density cultures. |
Gumus, A; Lee, S; Ahsan, SS; Karlsson, K; Gabrielson, R; Guglielmo, CG; ..., Lab-on-a-bird: biophysical monitoring of flying birds Journal Article PloS one, 10 (4), pp. 123947, 2015. @article{pop00011c, title = {Lab-on-a-bird: biophysical monitoring of flying birds}, author = {A Gumus and S Lee and SS Ahsan and K Karlsson and R Gabrielson and CG Guglielmo and ...}, year = {2015}, date = {2015-01-01}, journal = {PloS one}, volume = {10}, number = {4}, pages = {123947}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Ahsan, Syed Saad; Gumus, Abdurrahman; Erickson, David Stacked waveguide reactors with gradient embedded scatterers for high-capacity water cleaning Journal Article Optics Express, 2015. @article{Ahsan2015a, title = {Stacked waveguide reactors with gradient embedded scatterers for high-capacity water cleaning}, author = {Syed Saad Ahsan and Abdurrahman Gumus and David Erickson}, doi = {10.1364/oe.23.0a1664}, year = {2015}, date = {2015-01-01}, journal = {Optics Express}, abstract = {textcopyright 2015 Optical Society of America. We present a compact water-cleaning reactor with stacked layers of waveguides containing gradient patterns of optical scatterers that enable uniform light distribution and augmented water-cleaning rates. Previous photocatalytic reactors using immersion, external, or distributive lamps suffer from poor light distribution that impedes scalability. Here, we use an external UV-source to direct photons into stacked waveguide reactors where we scatter the photons uniformly over the length of the waveguide to thin films of TiO2-catalysts. We also show 4.5 times improvement in activity over uniform scatterer designs, demonstrate a degradation of 67% of the organic dye, and characterize the degradation rate constant.}, keywords = {}, pubstate = {published}, tppubtype = {article} } textcopyright 2015 Optical Society of America. We present a compact water-cleaning reactor with stacked layers of waveguides containing gradient patterns of optical scatterers that enable uniform light distribution and augmented water-cleaning rates. Previous photocatalytic reactors using immersion, external, or distributive lamps suffer from poor light distribution that impedes scalability. Here, we use an external UV-source to direct photons into stacked waveguide reactors where we scatter the photons uniformly over the length of the waveguide to thin films of TiO2-catalysts. We also show 4.5 times improvement in activity over uniform scatterer designs, demonstrate a degradation of 67% of the organic dye, and characterize the degradation rate constant. |
Dinleyici, MS Research Highlights: Elektrik-Elektronik Mühendisliği Bölümü Özel Sayısı Journal Article İzmir Yüksek Teknoloji Enstitüsü, 2015. @article{pop00021f, title = {Research Highlights: Elektrik-Elektronik Mühendisliği Bölümü Özel Sayısı}, author = {MS Dinleyici}, year = {2015}, date = {2015-01-01}, journal = {İzmir Yüksek Teknoloji Enstitüsü}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Gumus, A Bioelectronic systems in studying tissue engineering, real-time biophysical monitoring of birds and point-of-care diagnostics Journal Article Cornell University, 2015. @article{pop00023b, title = {Bioelectronic systems in studying tissue engineering, real-time biophysical monitoring of birds and point-of-care diagnostics}, author = {A Gumus}, year = {2015}, date = {2015-01-01}, journal = {Cornell University}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Bayrak, A; Dogan, F; Tatlicioglu, E; Ozdemirel, B Design of an experimental twin‐rotor multi‐input multi‐output system Journal Article Computer Applications in Engineering Education, 23 (4), pp. 578–586, 2015. @article{pop00018d, title = {Design of an experimental twin‐rotor multi‐input multi‐output system}, author = {A Bayrak and F Dogan and E Tatlicioglu and B Ozdemirel}, year = {2015}, date = {2015-01-01}, journal = {Computer Applications in Engineering Education}, volume = {23}, number = {4}, pages = {578--586}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Savaci, Acar F; Yilmaz, Serpil Bayesian Stable Mixture Model of State Densities of Generalized Chua's Circuit Journal Article International Journal of Bifurcation and Chaos, 2015, ISSN: 0218-1274. @article{Savaci2015, title = {Bayesian Stable Mixture Model of State Densities of Generalized Chua's Circuit}, author = {Acar F Savaci and Serpil Yilmaz}, doi = {10.1142/s0218127415500388}, issn = {0218-1274}, year = {2015}, date = {2015-01-01}, journal = {International Journal of Bifurcation and Chaos}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Erdoğan, E; Güçlüoğlu, T Performance Analysis of Maximal Ratio Transmission with Relay Selection in Two-way Relay Networks Over Nakagami-m Fading Channels Journal Article Wireless Personal Communications, pp. 1–17, 2015. @article{pop00059b, title = {Performance Analysis of Maximal Ratio Transmission with Relay Selection in Two-way Relay Networks Over Nakagami-m Fading Channels}, author = {E Erdoğan and T Güçlüoğlu}, year = {2015}, date = {2015-01-01}, journal = {Wireless Personal Communications}, pages = {1--17}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Ozan, Sukru; Gumustekin, Sevket Reconstruction of geometrical and reflectance properties of surfaces by using structured lighting Inproceedings 2015. @inproceedings{Ozan2015, title = {Reconstruction of geometrical and reflectance properties of surfaces by using structured lighting}, author = {Sukru Ozan and Sevket Gumustekin}, doi = {10.1109/siu.2015.7129805}, year = {2015}, date = {2015-01-01}, abstract = {It is not possible to perform a robust and dense surface reconstruction for plain colored surfaces which have insufficient surface features, and for surfaces which have specularity effect because of the material nature by using traditional stereo imaging methods. The proposed surface scanner system in this work makes it possible to get a robust and dense surface reconstruction even for plain colored and/or semi glossy surfaces. Reflection properties of the surface material are also reconstructed to some extent by using the information gathered after scanning process. Moreover, the experimental results are shown.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } It is not possible to perform a robust and dense surface reconstruction for plain colored surfaces which have insufficient surface features, and for surfaces which have specularity effect because of the material nature by using traditional stereo imaging methods. The proposed surface scanner system in this work makes it possible to get a robust and dense surface reconstruction even for plain colored and/or semi glossy surfaces. Reflection properties of the surface material are also reconstructed to some extent by using the information gathered after scanning process. Moreover, the experimental results are shown. |
Erdogan, E; Gucluoglu, T Simple outage probability bound for two-way relay networks with joint antenna and relay selection over Nakagami-m fading channels Journal Article IET Electronics Letters, 51 (5), pp. 415–417, 2015. @article{pop00060, title = {Simple outage probability bound for two-way relay networks with joint antenna and relay selection over Nakagami-m fading channels}, author = {E Erdogan and T Gucluoglu}, year = {2015}, date = {2015-01-01}, journal = {IET Electronics Letters}, volume = {51}, number = {5}, pages = {415--417}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Okur, B; Aksoy, O; Zergeroglu, E; Tatlicioglu, E Nonlinear robust control of tendon–driven robot manipulators Journal Article Journal of Intelligent & Robotic Systems, 80 (1), pp. 3–14, 2015. @article{pop00034b, title = {Nonlinear robust control of tendon–driven robot manipulators}, author = {B Okur and O Aksoy and E Zergeroglu and E Tatlicioglu}, year = {2015}, date = {2015-01-01}, journal = {Journal of Intelligent & Robotic Systems}, volume = {80}, number = {1}, pages = {3--14}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Şahin, Y; Erdoğan, E; Güçlüoğlu, T Detect and forward based two-way relay systems with maximum-ratio transceivers Journal Article 2015 23nd Signal Processing and Communications Applications Conference (SIU …, 2015. @article{pop00061b, title = {Detect and forward based two-way relay systems with maximum-ratio transceivers}, author = {Y Şahin and E Erdoğan and T Güçlüoğlu}, year = {2015}, date = {2015-01-01}, journal = {2015 23nd Signal Processing and Communications Applications Conference (SIU …}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Dogan, Merve K; Tatlicioglu, Enver; Zergeroglu, Erkan Operational/task space learning control of robot manipulators with dynamical uncertainties Inproceedings 2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings, 2015, ISBN: 9781479977871. @inproceedings{Dogan2015a, title = {Operational/task space learning control of robot manipulators with dynamical uncertainties}, author = {Merve K Dogan and Enver Tatlicioglu and Erkan Zergeroglu}, doi = {10.1109/CCA.2015.7320683}, isbn = {9781479977871}, year = {2015}, date = {2015-01-01}, booktitle = {2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Göceri, Evgin; Ünlü, Mehmet Zübeyir; Dicle, Oʇuz A comparative performance evaluation of various approaches for liver segmentation from SPIR images Journal Article Turkish Journal of Electrical Engineering and Computer Sciences, 2015, ISSN: 13036203. @article{Goceri2015, title = {A comparative performance evaluation of various approaches for liver segmentation from SPIR images}, author = {Evgin Göceri and Mehmet Zübeyir Ünlü and Oʇuz Dicle}, doi = {10.3906/elk-1304-36}, issn = {13036203}, year = {2015}, date = {2015-01-01}, journal = {Turkish Journal of Electrical Engineering and Computer Sciences}, abstract = {textcopyright TÜBITAK. Developing a robust method for liver segmentation from magnetic resonance images is a challenging task because of the similar intensity values between adjacent organs, the geometrically complex liver structure, and injection of contrast media. Most importantly, a high anatomical variability of a healthy or diseased liver is a major challenge in defining the exact boundaries of the liver. Several artifacts of pulsation, motion, and partial volume effects are also among the variety of factors that make automatic liver segmentation difficult. In this paper, we present an overview of liver segmentation methods in magnetic resonance images and show comparative results of seven different pseudo-3D liver segmentation approaches chosen from deterministic (K-means-based), probabilistic (Gaussian model-based), supervised neural network (multilayer perceptron-based), and deformable model-based (level set) segmentation methods. The results of quantitative and qualitative analyses using sensitivity, specificity, and accuracy metrics show that the multilayer perceptron-based approach and a level set-based approach, both of which use distance regularization terms and signed pressure force function, are the most successful methods for liver segmentation from spectral presaturation inversion recovery (SPIR) images. However, the multilayer perceptron-based segmentation method has a higher computational cost. The automatic method using the distance regularized level set evolution with signed pressure force function avoids the sensitivity of a user-defined initial contour for each slice, gives the most efficient results for liver segmentation after the preprocessing steps, and also requires less computational time.}, keywords = {}, pubstate = {published}, tppubtype = {article} } textcopyright TÜBITAK. Developing a robust method for liver segmentation from magnetic resonance images is a challenging task because of the similar intensity values between adjacent organs, the geometrically complex liver structure, and injection of contrast media. Most importantly, a high anatomical variability of a healthy or diseased liver is a major challenge in defining the exact boundaries of the liver. Several artifacts of pulsation, motion, and partial volume effects are also among the variety of factors that make automatic liver segmentation difficult. In this paper, we present an overview of liver segmentation methods in magnetic resonance images and show comparative results of seven different pseudo-3D liver segmentation approaches chosen from deterministic (K-means-based), probabilistic (Gaussian model-based), supervised neural network (multilayer perceptron-based), and deformable model-based (level set) segmentation methods. The results of quantitative and qualitative analyses using sensitivity, specificity, and accuracy metrics show that the multilayer perceptron-based approach and a level set-based approach, both of which use distance regularization terms and signed pressure force function, are the most successful methods for liver segmentation from spectral presaturation inversion recovery (SPIR) images. However, the multilayer perceptron-based segmentation method has a higher computational cost. The automatic method using the distance regularized level set evolution with signed pressure force function avoids the sensitivity of a user-defined initial contour for each slice, gives the most efficient results for liver segmentation after the preprocessing steps, and also requires less computational time. |
Okur, Beytullah; Zergeroglu, Erkan; Tatlicioglu, Enver Nonlinear control of tendon driven robot manipulators: Elimination of actuator side position measurements Inproceedings Proceedings of the IEEE Conference on Decision and Control, 2015, ISSN: 07431546. @inproceedings{Okur2015a, title = {Nonlinear control of tendon driven robot manipulators: Elimination of actuator side position measurements}, author = {Beytullah Okur and Erkan Zergeroglu and Enver Tatlicioglu}, doi = {10.1109/CDC.2015.7402421}, issn = {07431546}, year = {2015}, date = {2015-01-01}, booktitle = {Proceedings of the IEEE Conference on Decision and Control}, abstract = {textcopyright 2015 IEEE. In this study, a partial state feedback controller is proposed for the link position tracking control problem of flexible tendon driven robotic systems. Specifically; a nonlinear model based controller is formulated for tendon driven robot manipulators under the constraint that only the link position and tendon expansion force measurements are available. Despite the lack of link and actuator side velocity and actuator position measurements, the proposed controller ensures exponential link position tracking. To eliminate the need of actuator position and velocity measurements, a model based velocity observer has been utilized. Stability of the closed loop system and boundedness of system states are proven via Lyapunov based arguments. The performance of the purposed observer-controller couple is then verified by a set of numerical simulations.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } textcopyright 2015 IEEE. In this study, a partial state feedback controller is proposed for the link position tracking control problem of flexible tendon driven robotic systems. Specifically; a nonlinear model based controller is formulated for tendon driven robot manipulators under the constraint that only the link position and tendon expansion force measurements are available. Despite the lack of link and actuator side velocity and actuator position measurements, the proposed controller ensures exponential link position tracking. To eliminate the need of actuator position and velocity measurements, a model based velocity observer has been utilized. Stability of the closed loop system and boundedness of system states are proven via Lyapunov based arguments. The performance of the purposed observer-controller couple is then verified by a set of numerical simulations. |
Cetin, Kamil; Tatlicioglu, Enver; Zergeroglu, Erkan Continuous robust task-space tracking control of robotic manipulators with uncertain dynamics Inproceedings 2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings, 2015, ISBN: 9781479977871. @inproceedings{Cetin2015, title = {Continuous robust task-space tracking control of robotic manipulators with uncertain dynamics}, author = {Kamil Cetin and Enver Tatlicioglu and Erkan Zergeroglu}, doi = {10.1109/CCA.2015.7320647}, isbn = {9781479977871}, year = {2015}, date = {2015-01-01}, booktitle = {2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings}, abstract = {textcopyright 2015 IEEE.In this work, the problem of robust task space control of robotic manipulators with continuous control inputs have been considered. Under mild assumptions on kinematic formulation and dynamics of the robot manipulator, a continuous robust controller have been proposed. The proposed controller ensures asymptotic end-effector tracking despite the presence of unstructured uncertainties associated with the dynamical terms. Numerical simulations conducted on a two degree-of-freedom robot manipulator is also presented to illustrate the feasibility and performance of the proposed controller.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } textcopyright 2015 IEEE.In this work, the problem of robust task space control of robotic manipulators with continuous control inputs have been considered. Under mild assumptions on kinematic formulation and dynamics of the robot manipulator, a continuous robust controller have been proposed. The proposed controller ensures asymptotic end-effector tracking despite the presence of unstructured uncertainties associated with the dynamical terms. Numerical simulations conducted on a two degree-of-freedom robot manipulator is also presented to illustrate the feasibility and performance of the proposed controller. |
Bayrak, Alper; Tatlicioglu, Enver; Zergeroglu, Erkan; Deniz, Meryem A new continuous velocity observer formulation for a class of uncertain nonlinear mechanical systems Inproceedings 2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings, 2015, ISBN: 9781479977871. @inproceedings{Bayrak2015a, title = {A new continuous velocity observer formulation for a class of uncertain nonlinear mechanical systems}, author = {Alper Bayrak and Enver Tatlicioglu and Erkan Zergeroglu and Meryem Deniz}, doi = {10.1109/CCA.2015.7320788}, isbn = {9781479977871}, year = {2015}, date = {2015-01-01}, booktitle = {2015 IEEE Conference on Control and Applications, CCA 2015 - Proceedings}, abstract = {textcopyright 2015 IEEE.In this study, we present a smooth robust velocity observer for a class of uncertain nonlinear mechanical systems. The smoothness of the observers is guaranteed by utilizing hyperbolic tangent function as opposed to signum-type functions applied in most robust and sliding mode observers found in the literature. The proposed observer does not require a priori knowledge of an upper bound of the uncertain system dynamics and introduces a time-varying observer gain for uncertainty compensation. Practical stability of the observer error is ensured via Lyapunov-type stability analysis. Numerical simulation studies backed up by experimental results are presented to illustrate the performance of the proposed observer.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } textcopyright 2015 IEEE.In this study, we present a smooth robust velocity observer for a class of uncertain nonlinear mechanical systems. The smoothness of the observers is guaranteed by utilizing hyperbolic tangent function as opposed to signum-type functions applied in most robust and sliding mode observers found in the literature. The proposed observer does not require a priori knowledge of an upper bound of the uncertain system dynamics and introduces a time-varying observer gain for uncertainty compensation. Practical stability of the observer error is ensured via Lyapunov-type stability analysis. Numerical simulation studies backed up by experimental results are presented to illustrate the performance of the proposed observer. |
Bidikli, Baris; Tatlicioglu, Enver; Zergeroglu, Erkan Robust control of a rigid link in a cross flow Inproceedings 2015 European Control Conference, ECC 2015, 2015, ISBN: 9783952426937. @inproceedings{Bidikli2015a, title = {Robust control of a rigid link in a cross flow}, author = {Baris Bidikli and Enver Tatlicioglu and Erkan Zergeroglu}, doi = {10.1109/ECC.2015.7330709}, isbn = {9783952426937}, year = {2015}, date = {2015-01-01}, booktitle = {2015 European Control Conference, ECC 2015}, abstract = {Remotely operated vehicles equipped with a robotic manipulator are utilized in several underwater/deep sea applications. Control of these type of systems are mostly provided by obtaining the proper position for the end effector of robotic manipulator which constitutes the desired motion for remotely operated vehicle. This situation makes the control of robotic manipulators is really important subject for underwater applications. In this work, we study tracking control of a one degree-of-freedom rigid link in a cross flow. Systems operating at underwater (including this one) are hard to model accurately, and as a result their models include several uncertainties. To reject these modeling uncertainties and external ones, two robust controllers are proposed. Stability of the closed-loop system and the asymptotic convergence of the tracking error are proven mathematically. Numerical simulations are performed to demonstrate the viability of the proposed controller. textcopyright 2015 EUCA.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Remotely operated vehicles equipped with a robotic manipulator are utilized in several underwater/deep sea applications. Control of these type of systems are mostly provided by obtaining the proper position for the end effector of robotic manipulator which constitutes the desired motion for remotely operated vehicle. This situation makes the control of robotic manipulators is really important subject for underwater applications. In this work, we study tracking control of a one degree-of-freedom rigid link in a cross flow. Systems operating at underwater (including this one) are hard to model accurately, and as a result their models include several uncertainties. To reject these modeling uncertainties and external ones, two robust controllers are proposed. Stability of the closed-loop system and the asymptotic convergence of the tracking error are proven mathematically. Numerical simulations are performed to demonstrate the viability of the proposed controller. textcopyright 2015 EUCA. |
Kustepeli, Alp Revised Distributional Forms of the Laplacian and Poisson's Equation, Their Implications, and All Related Generalizations Journal Article Electromagnetics, 2015, ISSN: 1532527X. @article{Kustepeli2015, title = {Revised Distributional Forms of the Laplacian and Poisson's Equation, Their Implications, and All Related Generalizations}, author = {Alp Kustepeli}, doi = {10.1080/02726343.2015.1053349}, issn = {1532527X}, year = {2015}, date = {2015-01-01}, journal = {Electromagnetics}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Dogan, Merve K; Tatlicioglu, Enver; Zergeroglu, Erkan; Cetin, Kamil Lyapunov-based output feedback learning control of robot manipulators Inproceedings Proceedings of the American Control Conference, 2015, ISSN: 07431619. @inproceedings{Dogan2015b, title = {Lyapunov-based output feedback learning control of robot manipulators}, author = {Merve K Dogan and Enver Tatlicioglu and Erkan Zergeroglu and Kamil Cetin}, doi = {10.1109/ACC.2015.7172173}, issn = {07431619}, year = {2015}, date = {2015-01-01}, booktitle = {Proceedings of the American Control Conference}, abstract = {textcopyright 2015 American Automatic Control Council.This paper address the output feedback learning tracking control problem for robot manipulators with repetitive desired joint level trajectories. Specifically, an observer-based output feedback learning controller for periodic trajectories with known period have been proposed. The proposed learning controller guarantees semi-global asymptotic tracking despite the existence of parametric uncertainties associated with the robot dynamics and lack of velocity measurements. A learning-based feedforward term in conjunction with a novel observer formulation is designed to obtain the aforementioned result. The stability of the controller-observer couple is guaranteed via Lyapunov based arguments. Numerical studies performed on a two link robot manipulator are also presented to demonstrate the viability of the proposed method.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } textcopyright 2015 American Automatic Control Council.This paper address the output feedback learning tracking control problem for robot manipulators with repetitive desired joint level trajectories. Specifically, an observer-based output feedback learning controller for periodic trajectories with known period have been proposed. The proposed learning controller guarantees semi-global asymptotic tracking despite the existence of parametric uncertainties associated with the robot dynamics and lack of velocity measurements. A learning-based feedforward term in conjunction with a novel observer formulation is designed to obtain the aforementioned result. The stability of the controller-observer couple is guaranteed via Lyapunov based arguments. Numerical studies performed on a two link robot manipulator are also presented to demonstrate the viability of the proposed method. |
Bayrak, Alper; Dogan, Firat; Tatlicioglu, Enver; Ozdemirel, Barbaros Design of an experimental twin-rotor multi-input multi-output system Journal Article Computer Applications in Engineering Education, 2015, ISSN: 10990542. @article{Bayrak2015b, title = {Design of an experimental twin-rotor multi-input multi-output system}, author = {Alper Bayrak and Firat Dogan and Enver Tatlicioglu and Barbaros Ozdemirel}, doi = {10.1002/cae.21628}, issn = {10990542}, year = {2015}, date = {2015-01-01}, journal = {Computer Applications in Engineering Education}, abstract = {textcopyright 2015 Wiley Periodicals, Inc.Twin-rotor multi-input multi-output system (TRMS) is a popular experimental setup utilized mostly for development and evaluation of aerovehicle control algorithms. Motivated by its popularity, construction steps of a TRMS setup in an academic setting are presented in this paper. Specifically, design of mechanical and electronic hardware components and development of related computer software are described in detail. Preliminary experiment results are also presented to demonstrate the performance of the system.}, keywords = {}, pubstate = {published}, tppubtype = {article} } textcopyright 2015 Wiley Periodicals, Inc.Twin-rotor multi-input multi-output system (TRMS) is a popular experimental setup utilized mostly for development and evaluation of aerovehicle control algorithms. Motivated by its popularity, construction steps of a TRMS setup in an academic setting are presented in this paper. Specifically, design of mechanical and electronic hardware components and development of related computer software are described in detail. Preliminary experiment results are also presented to demonstrate the performance of the system. |
Deniz, Meryem; Bidikli, Baris; Bayrak, Alper; Ozdemirel, Barbaros; Tatlicioglu, Enver Modelling twin rotor system with artificial neural networks Inproceedings 2015. @inproceedings{Deniz2015, title = {Modelling twin rotor system with artificial neural networks}, author = {Meryem Deniz and Baris Bidikli and Alper Bayrak and Barbaros Ozdemirel and Enver Tatlicioglu}, doi = {10.1109/siu.2015.7130042}, year = {2015}, date = {2015-01-01}, abstract = {In this study, the input output relation of the twin rotor system which was constructed in our laboratory is obtained by using ANNs. When compared with the existing literature, main advantage of this modelling approach is that multi input multi output ANN structure is used preferred. As a result of this approach, the cross coupling effects, between the rotors and also between the outputs, are taken into consideration. Thus, we sincerely believe that the obtained input output model demonstrates a close behavior to the real system.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } In this study, the input output relation of the twin rotor system which was constructed in our laboratory is obtained by using ANNs. When compared with the existing literature, main advantage of this modelling approach is that multi input multi output ANN structure is used preferred. As a result of this approach, the cross coupling effects, between the rotors and also between the outputs, are taken into consideration. Thus, we sincerely believe that the obtained input output model demonstrates a close behavior to the real system. |
Aksoy, Orhan; Zergeroglu, Erkan; Tatlicioglu, Enver Inverse optimal adaptive output feedback control of Euler-Lagrange systems: A variable structure observer based approach Inproceedings Proceedings of the IEEE Conference on Decision and Control, 2015, ISSN: 07431546. @inproceedings{Aksoy2015, title = {Inverse optimal adaptive output feedback control of Euler-Lagrange systems: A variable structure observer based approach}, author = {Orhan Aksoy and Erkan Zergeroglu and Enver Tatlicioglu}, doi = {10.1109/CDC.2015.7403427}, issn = {07431546}, year = {2015}, date = {2015-01-01}, booktitle = {Proceedings of the IEEE Conference on Decision and Control}, abstract = {— This work focuses on inverse optimal, observer based output feedback control of Euler-Lagrange systems. Specifically a variable structure observer based output feedback controller is proposed which aside from ensuring asymptotic position tracking also ensures that a positive cost function, penalizing control input performance, is minimized. Simulation studies performed on a two link planar robot manipulator are included to illustrate the overall performance and feasibility of the proposed controller.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } — This work focuses on inverse optimal, observer based output feedback control of Euler-Lagrange systems. Specifically a variable structure observer based output feedback controller is proposed which aside from ensuring asymptotic position tracking also ensures that a positive cost function, penalizing control input performance, is minimized. Simulation studies performed on a two link planar robot manipulator are included to illustrate the overall performance and feasibility of the proposed controller. |
Bidikli, Baris; Tatlicioglu, Enver; Zergeroglu, Erkan Robust control design for positioning of an unactuated surface vessel Inproceedings IEEE International Conference on Intelligent Robots and Systems, 2015, ISSN: 21530866. @inproceedings{Bidikli2015b, title = {Robust control design for positioning of an unactuated surface vessel}, author = {Baris Bidikli and Enver Tatlicioglu and Erkan Zergeroglu}, doi = {10.1109/IROS.2015.7353503}, issn = {21530866}, year = {2015}, date = {2015-01-01}, booktitle = {IEEE International Conference on Intelligent Robots and Systems}, abstract = {In this paper, a robust controller is designed to achieve accurate positioning of an unactuated surface vessel by using multiple unidirectional tugboats. After initially locating opposing tugboats to specific configurations, the control problem is transformed into a second order system with an uncertain non-symmetric input gain matrix. Upon applying a matrix decomposition, a robust controller is proposed. Detailed stability analysis ensured asymptotic tracking. Numerical simulation results demonstrate the efficiency of the proposed controller.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } In this paper, a robust controller is designed to achieve accurate positioning of an unactuated surface vessel by using multiple unidirectional tugboats. After initially locating opposing tugboats to specific configurations, the control problem is transformed into a second order system with an uncertain non-symmetric input gain matrix. Upon applying a matrix decomposition, a robust controller is proposed. Detailed stability analysis ensured asymptotic tracking. Numerical simulation results demonstrate the efficiency of the proposed controller. |
Bidikli, Baris; Tatlicioglu, Enver; Zergeroglu, Erkan Robust control design for positioning of an unactuated surface vessel Inproceedings IEEE International Conference on Intelligent Robots and Systems, 2015, ISSN: 21530866. @inproceedings{Bidikli2015c, title = {Robust control design for positioning of an unactuated surface vessel}, author = {Baris Bidikli and Enver Tatlicioglu and Erkan Zergeroglu}, doi = {10.1109/IROS.2015.7353503}, issn = {21530866}, year = {2015}, date = {2015-01-01}, booktitle = {IEEE International Conference on Intelligent Robots and Systems}, abstract = {In this paper, a robust controller is designed to achieve accurate positioning of an unactuated surface vessel by using multiple unidirectional tugboats. After initially locating opposing tugboats to specific configurations, the control problem is transformed into a second order system with an uncertain non-symmetric input gain matrix. Upon applying a matrix decomposition, a robust controller is proposed. Detailed stability analysis ensured asymptotic tracking. Numerical simulation results demonstrate the efficiency of the proposed controller.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } In this paper, a robust controller is designed to achieve accurate positioning of an unactuated surface vessel by using multiple unidirectional tugboats. After initially locating opposing tugboats to specific configurations, the control problem is transformed into a second order system with an uncertain non-symmetric input gain matrix. Upon applying a matrix decomposition, a robust controller is proposed. Detailed stability analysis ensured asymptotic tracking. Numerical simulation results demonstrate the efficiency of the proposed controller. |