Now showing items 1-20 of 35

    • Automatic detection of geospatial objects using multiple hierarchical segmentations 

      Akçay, H. G.; Aksoy, S. (Institute of Electrical and Electronics Engineers, 2008-07)
      The object-based analysis of remotely sensed imagery provides valuable spatial and structural information that is complementary to pixel-based spectral information in classification. In this paper, we present novel methods ...
    • Conditional steady-state bounds for a subset of states in Markov chains 

      Dayar, T.; Pekergin, N.; Younès, S. (2006)
      The problem of computing bounds on the conditional steady-state probability vector of a subset of states in finite, ergodic discrete-time Markov chains (DTMCs) is considered. An improved algorithm utilizing the strong ...
    • Continuous and discrete fractional fourier domain decomposition 

      Kutay, M. A.; Özaktaş, H. M.; Yetik, İ. Ş.; Özaktaş, H. (IEEE (Institute of Electrical and Electronics Engineers), 2000)
      We introduce the fractional Fourier domain decomposition for continuous and discrete signals and systems. A procedure called pruning, analogous to truncation of the singular-value decomposition, underlies a number of ...
    • Differential privacy with bounded priors: Reconciling utility and privacy in genome-wide association studies 

      Tramèr F.; Huang, Z.; Hubaux J.-P.; Ayday, E. (Association for Computing Machinery, 2015)
      Differential privacy (DP) has become widely accepted as a rigorous definition of data privacy, with stronger privacy guarantees than traditional statistical methods. However, recent studies have shown that for reasonable ...
    • Efficient algorithm to extract components of a composite signal 

      Özdemir, A. K.; Arıkan, O. (IEEE (Institute of Electrical and Electronics Engineers), 2000)
      An efficient algorithm is proposed to extract components of a composite signal. The proposed approach has two stages of processing in which the time-frequency supports of the individual signal components are identified and ...
    • Estimating distributions varying in time in a universal manner 

      Gokcesu, K.; Manis, E.; Kurt, A. E.; Yar, E. (Institute of Electrical and Electronics Engineers Inc., 2017)
      We investigate the estimation of distributions with time-varying parameters. We introduce an algorithm that achieves the optimal negative likelihood performance against the true probability distribution. We achieve this ...
    • Fast computation of the ambiguity function and the Wigner distribution on arbitrary line segments 

      Özdemir, A. K.; Arıkan, O. (IEEE, 2001)
      By using the fractional Fourier transformation of the time-domain signals, closed-form expressions for the projections of their auto or cross ambiguity functions are derived. Based on a similar formulation for the projections ...
    • Finding compound structures in images using image segmentation and graph-based knowledge discovery 

      Zamalieva, D.; Aksoy, S.; Tilton J.C. (2009)
      We present an unsupervised method for discovering compound image structures that are comprised of simpler primitive objects. An initial segmentation step produces image regions with homogeneous spectral content. Then, the ...
    • Fitting matrix geometric distributions by model reduction 

      Akar, N. (Taylor and Francis Inc., 2015)
      A novel algorithmic method is proposed to fit matrix geometric distributions of desired order to empirical data or arbitrary discrete distributions. The proposed method effectively combines two existing approaches from two ...
    • A general theory on spectral properties of state-homogeneous finite-state quasi-birth-death processes 

      Fadıloğlu, M. M.; Yeralan, S. (Elsevier, 2001)
      In this paper a spectral theory pertaining to Quasi-Birth–Death Processes (QBDs) is presented. The QBD, which is a generalization of the birth–death process, is a powerful tool that can be utilized in modeling many stochastic ...
    • GenoGuard: protecting genomic data against brute-force attacks 

      Huang Z.; Ayday, E.; Fellay J.; Hubaux, Jean-Pierre; Juels, A. (Institute of Electrical and Electronics Engineers Inc., 2015)
      Secure storage of genomic data is of great and increasing importance. The scientific community's improving ability to interpret individuals' genetic materials and the growing size of genetic database populations have been ...
    • Guessing with lies 

      Arikan, E.; Boztaş, S. (2002)
      A practical algorithm was obtained for directly generating an optimal guessing sequence for guessing under lies. An optimal guessing strategy was defined as one which minimizes the number of average number of guesses in ...
    • High resolution time frequency representation with significantly reduced cross-terms 

      Özdemir, K. A.; Arıkan, O. (Institute of Electrical and Electronics Engineers, 2000)
      A novel algorithm is proposed for efficiently smoothing the slices of the Wigner distribution by exploiting the recently developed relation between the Radon transform of the ambiguity function and the fractional Fourier ...
    • Language evolution and information theory 

      Ahlswede, R.; Arikan, E.; Bäumer L.; Deppe, C. (2004)
      The use of Nowak's model to study the language evolution and to settle a conjecture by Nowak was discussed. These models explained the ways by which natural selection can lead to the gradual emergence of human language. ...
    • Large deviations of probability rank 

      Arikan, E. (2000)
      Consider a pair of random variables (X,Y) with distribution P. The probability rank function is defined so that G(x|y) = 1 for the most probable outcome x conditional on Y = y, G(x|y) = 2 for the second most probable ...
    • A matrix analytical method for the discrete time Lindley equation using the generalized Schur decomposition 

      Akar, N. (2006)
      In this paper, we study the discrete time Lindley equation governing an infinite size GI/GI/1 queue. In this queuing system, the arrivals and services are independent and identically distributed but they obey a discrete ...
    • A new approach to time-frequency localized signal design 

      Özdemir, A.K.; Aydin, Z.; Arikan, O. (2002)
      A novel approach is presented for the design of signals in Wigner Domain. In this method, the desired signal features in the time-frequency domain are specified in two stages. First the user specifies the spine curve around ...
    • Noise-enhanced M-ary hypothesis-testing in the minimax framework 

      Bayram, S.; Gezici, S. (2009)
      In this study, the effects of adding independent noise to observations of a suboptimal detector are studied for M-ary hypothesis-testing problems according to the minimax criterion. It is shown that the optimal additional ...
    • Non-Boltzmann stationary distributions and nonequilibrium relations in active baths 

      Argun, A.; Moradi A.-R.; Pinçe, E.; Bagci, G. B.; Imparato, A.; Volpe, G. (American Physical Society, 2016-12)
      Most natural and engineered processes, such as biomolecular reactions, protein folding, and population dynamics, occur far from equilibrium and therefore cannot be treated within the framework of classical equilibrium ...
    • Non-linear pricing by convex duality 

      Pınar, M. Ç. (Elsevier, 2015)
      We consider the pricing problem of a risk-neutral monopolist who produces (at a cost) and offers an infinitely divisible good to a single potential buyer that can be of a finite number of (single dimensional) types. The ...